Installation and Oil condensing boiler Maintenance ... · 5.4.3 Installation of system components 23 5.5 Filling the heating system and checking for leaks 24 5.6 Connecting the fuel

For contractors

Please read carefully prior to installation and servicing.

CAUTION!Observe the safety instructions of this installation and maintenance manual before placing the boiler in operation.

DANGER! If installation, adjustment, modification, operation or maintenance of the heating system is carried out by an unqualified person, this may result in danger to life and limb or property damage.The directions of this installation and maintenance manual must be followed precisely.If you require assistance or further information, con-tact a qualified installer or an appropriate service provider.

CAUTION!The operating manual is a component of the techni-cal documentation and must be handed over to the operator of the heating system. Discuss the instruction in this manual with the ow-ner or operator of the heating system to ensure that they are familiar with all information required for operation of the heating system.

Installation and Maintenance Instructions

Oil condensing boiler

Logano GB125 BE US/CA

6 72

0 64

7 54

8 - 0

1/20

11 U

S/C

A

Contents

Logano GB125 BE US/CA - Subject to technical modifications.2

Contents

1 Safety instructions and explanation ofsymbols 3

1.1 Safety instructions 31.2 Explanation of symbols 4

2 Product description 52.1 Intended use 52.2 Standards, regulations and code compliance 52.3 Notes on installation and operation 52.4 Product description 62.5 Boiler water quality 72.6 Tools, Materials and Accessories 72.7 Scope of delivery 72.8 Dimensions and specifications 82.9 Conditions for operation 92.9.1 General operating conditions 92.9.2 Conditions for the boiler room

and the environment 102.9.3 Fuel conditions 102.9.4 Power supply conditions 102.9.5 Conditions for hydraulic system and water quality 112.10 Disposal 11

3 Moving the boiler 123.1 Reducing the boiler weight for handling purposes 123.2 Lifting and carrying the boiler 133.3 Moving the boiler with hand truck 13

4 Placing the boiler 144.1 Wall clearances 144.2 Reversing the burner door 154.3 Mounting the adjustable feet (included with B-kit) 164.4 Positioning and leveling the boiler 16

5 Installing the boiler 175.1 Flue pipe installation 175.2 Test ports 185.3 Installation options 205.4 Making the water connections 225.4.1 Installing B-kit 225.4.2 Mounting the drain valve (included with B-kit) 235.4.3 Installation of system components 235.5 Filling the heating system and checking for leaks 245.6 Connecting the fuel supply 255.7 Bleed off condensate 265.8 Electrical supply connections 275.8.1 Installing the control panel 275.8.2 Installing the temperature sensor assembly 285.8.3 Power connection and connections of additional

components 295.8.4 Installing cable strain relief 305.9 Installing the back boiler cover 30

6 Starting up the heating system 316.1 Bringing the system up to operating pressure 316.2 Testing safety valve 326.3 Checking position of heat exchanger baffles 326.4 Preparing the heating system for operation 326.5 Starting up the control panel and the burner 336.6 Taking measurements 336.7 Checking the manual reset high limit (STB) 346.8 Installing the burner hood 346.9 Commissioning log 35

7 Shutting down the heating system 367.1 Normal shut-down 367.2 Shutting down the heating system in an

emergency 367.2.1 Action in an emergency 36

8 Heating system inspection 378.1 Why is regular maintenance important? 378.2 Preparing the boiler for inspection 378.3 Cleaning the boiler 388.3.1 Cleaning the boiler with cleaning brushes 388.3.2 Wet cleaning (chemical cleaning) 398.4 Cleaning the heat exchanger system 408.5 Cleaning the neutralization and siphon 428.6 Checking the air supply hose 438.7 Check heating system operating pressure 438.8 Test safety valve 448.9 Concentric supply air and flue gas routing 448.10 Air supply system 448.11 Inspection and maintenance reports 45

9 Troubleshooting 48

10 Examples of installations 49

11 Spare parts 52

12 Wiring diagrams 60

Index 61

1Safety instructions and explanation of symbols

Logano GB125 BE US/CA - Subject to technical modifications. 3

1 Safety instructions and explanation of symbols

1.1 Safety instructions

If you smell flue gasB Switch off the boiler ( page 36).B Open windows and doors.B Inform an authorized heating contractor.

Risk of poisoning. An insufficient supply of air can result in dangerous escape of flue gas.B Never close off or reduce the size of air intake and

outlet openings.B The boiler must not be operated until the obstruction

has been removed.B Ensure that no mechanical air-extraction equipment

draws air from the boiler room, e.g. kitchen vent hood, clothes dryer, central vacuum system, etc.

B Inform the system user in writing of an existing problem and associated dangers.

Danger from escaping flue gasesB Make sure that the vent pipes and gaskets are not

damaged.B Use silicone as sealing compound.B Never operate this boiler with a barometric or a

thermally-controlled vent damper.B Connect only one boiler to each venting system or

chimney flue.B The venting system piping must not feed into another

air extraction duct. B Do not route the venting system piping through or

inside another duct used for exhaust air or other flue gases.

B To prevent the combustion gases from reaching the boiler room, the siphon must always be filled with water.

Dangers posed by explosive and combustible materialsB Do not use or store easily-combustible materials

(paper, lace curtains, clothing, thinners, paints, etc.) near the boiler.

B Maintain a clearance of 16 inches (40.6 cm) from the boiler.

Combustion airB Keep the supply of combustion air free of corrosive

substances (e.g. halogenated hydrocarbons that contain chlorine or fluorine compounds). This will help prevent corrosion.

Danger from electrical shockB Before opening the boiler:

Disconnect the heating system from the electrical power supply by means of the emergency shutoff switch or the heating system circuit breaker on the main fuse panel.

B It is not sufficient just to switch off the control panel.B Take measures to ensure that the heating system

cannot be switched on again unintentionally.

InstallationB Correct and proper installation and adjustment of the

burner and the control panel are the fundamental requirements for safe and economical operation of the boiler.

B The boiler may only be installed or maintained by an approved heating contractor.

B Do not modify any parts that carry flue gases.B Only qualified electricians are permitted to carry out

electrical work. Follow applicable code.B The hot water tank may only be used for heating

domestic hot water.B Never shut off safety valves!

Water may escape from the safety valve when it is being heated.

Danger due to failing to consider your own safety in an emergency such as a fireB Never put yourself at risk of fatal injury. Your own safety

must always take the highest priority.

1 Safety instructions and explanation of symbols


Inspection/maintenanceHeating systems must be maintained regularly.

This way, they maintain a high level of efficiency and low fuel consumption.

You will achieve a high level of operational safety.

And you will obtain the cleanest possible combustion.

B Recommendation for customers: take out a maintenance and inspection contract with an approved heating contractor covering annual inspection and condition-based maintenance.

B Maintenance and repairs may only be carried out by an approved heating contractor.

B Have any faults corrected immediately in order to prevent damage to the system.

B Use only genuine spare parts. Damage caused by the use of parts not supplied by Buderus is not covered by the Buderus warranty.

Instructing the customerB Explain to the customer how the boiler works and how

to operate it.B Inform the customer that he/she must not carry out any

alterations or repairs.

1.2 Explanation of symbols

Signal words are used to indicate the seriousness of the ensuing risk if measures for minimizing damage are not taken.

• Caution indicates that minor damage to property may occur.

• Warning means that minor injury or severe property damage may occur.

• Danger means that severe injury may occur. Very serious cases may result in death.

Notes contain important additional information.

Notes do not contain any warnings or information about hazards or risks.

Cross-references to particular places in the document or to other documents are marked with an arrow .

Warnings are indicated by a warning triangle and a gray background.

Notesare identified in the text by this symbol. They are separated by horizontal lines above and below the text.

2Product description


2 Product descriptionThis installation and maintenance manual contains important information for the safe and correct installation, initial start-up and maintenance of this boiler.

The Logano GB125 BE oil-fired condensing boiler is generally referred to below simply as the boiler.

These installation and maintenance instructions are designed for specialists, who – through their vocational training and experience –are knowledgeable in handling heating systems and DHW installations.

This boiler must only be installed with one of the Buderus supplied concentric supply air and flue gas routing systems.

• Concentric air supply and flue pipe exiting through external wall

• Concentric supply air and flue gas routing via roof• Concentric supply air/flue gas routing through a flue

inside a duct

This boiler produces significant amounts of acidic flue gas condensate while in operation. Condensate may cause damage to sewer pipes and septic systems, and disposal may be subject to local regulations. In the absence of such regulations Buderus recommends a condensate neutralization kit.

The boiler must draw all combustion air from the outside.

2.1 Intended useThe boiler is designed for the central heating and indirect heating of domestic hot water (e.g. in a hot water tank), for instance in single family homes or multi-family buildings.

2.2 Standards, regulations and code compliance

2.3 Notes on installation and operationWhen installing and operating the heating system observe the following:

• The local building codes regarding the installation• The local building codes regarding combustion air

supply and venting systems, and the chimney connection

• Regulations governing power connection to the power supply

• The regulations and standards relating to the safety systems for the water heating system

Other important information• Only operate the boiler with the combined combustion

air/flue venting system specifically designed and approved for it.

• Follow the local code when connecting the condensate outlet to the public sewer system.

It is the installer's responsibility to ensure the installation and operation of this heating system meets all applicable federal, state, and local codes.

The boiler must be installed by a qualified installer and in accordance with all requirements of NFPA-31, "Installation of Oil-Burning Equipment". Installation must comply with all local and national legal requirements and the regulations of all institutions having legislative authority with regard to the installation of oil-fired boilers.For Canada, the guidelines of the CSA/CGA B139 Installation Code apply.

2 Product description


2.4 Product descriptionThis boiler is an oil-fired condensing boiler with modulating control of boiler water temperature.

The boiler consists of:• Control panel• Boiler casing• Boiler block with thermal insulation• Burner • Heat exchanger system

The control panel monitors and controls all electrical boiler components.

The boiler casing prevents heat loss and reduces noise.

The boiler block transfers the heat generated by the burner to the boiler water. The insulation prevents energy loss.

Fig. 1 Boiler with burner

1 Control panel2 Boiler casing3 Boiler block with thermal insulation4 Burner hood5 Burner

Fig. 2 Rear view with heat exchanger (thermal insulation not shown)

1 Heat exchanger system



2.5 Boiler water qualityPoor water quality can damage heating systems due to scale formation and corrosion. (Tab. 8, page 11).

2.6 Tools, Materials and AccessoriesFor the installation and maintenance of the boiler, you need standard tools used for central heating and DHW systems, plus metric wrenches and metric Allen wrenches.

The following may also prove useful:• Hand truck with securing strap or Buderus boiler cart• Wood battens• Cleaning brushes and/or chemical cleaning agent for

wet cleaning

2.7 Scope of deliveryB After delivery, check all packaging for perfect

condition.B Check the delivery for completeness.

CAUTION: Risk of system damage due to unsuitable boiler water!B When using oxygen-permeable pipes, e.

g. for radiant floor heating systems, you must separate the system using heat exchangers. Unsuitable heating system water promotes sludge formation and corrosion. This can result in heat exchanger malfunction and damage.

Component Qty Packaging

Boiler block 1 1 pallet

Boiler casing, factory-installed on the boiler block

Burner hood, factory-installed on the boiler block

Heat exchanger system, factory-installed on the boiler block

Oil burner with factory-installed burner door

Air supply hose, factory-installed

Siphon 1 1 bag1)

1) Under the burner hood

B-kit components:• Conversion nipple

(1¼ " NPT)• 30 psi safety valve• Drain valve (¾ ")• Pressure/temperature

gauge• Double nipple

(1¼ " NPT × R1¼ )• 90°-elbow (1¼ ” NPT)• 90°-elbow (¾ " NPT)• Screw set (for burner

mounting)• Adjustable feet

1 1 foil package1)

Control panel 1 1 box

Tigerloop oil filter and de-aerator

1 1 box

Technical documentation 1 bag

Tab. 1 Scope of delivery



2.8 Dimensions and specifications

Fig. 3 Connections and dimensions (measurements in inches)

VK = Boiler supplyRK = Boiler returnEL = Boiler drain (connection for drain valve)

Dimensions and connections:

Boiler type Unit GB125/22 BE GB125/30 BE GB125/35 BE

Boiler sections 3 4 4

Rated heat output (gross output)

131/86 °F

MBtu/hr 76 102 124

Rated heat output (net IBR rating)

131/86 °F

MBtu/hr 67 90 109

Rated heat output/heating capacity

(gross output)176/140 °F

MBtu/hr 75 100 121

Rated heat output

(net IBR rating)176/140 °F

MBtu/hr 65 87 105

Rated thermal input/burner input MBtu/hr 81 108 131

AFUE % 91.2 91.1 91.0

Flue gas temperature 176/140 °F °F (°C) 176 (80) 176 (80) 192 (89)

Boiler water content gal (l) 8.7 (35.6) 11.8 (44.9) 11.8 (44.9)

Gas volume of combustion chamber and heat

exchanger

cu. ft.

(l)

1.5 (42.9) 2.0 (57.9) 2.0 (57.9)

Oil consumption/oil firing rate gph (l/h) 0.60 (2.3) 0.75 (2.9) 0.95 (3.6)

Flue gas resistance in. W.C.

(Pa)

0.08" - 0.14" W.C. (20 - 35)

Heat exchanger water pressure drop

(DeltaT = 18 °F)

ft. of

head

(mbar)

1.8' (54) 2.0' (60) 2.7' (81)

Maximum supply temperature1)

1) Safety limit (manual reset high limit, STB)Maximum permitted supply temperature = manual reset high limit (STB) – 32 °FExample: manual reset high limit (STB) = 212 °F, maximum possible supply temperature = 212 - 32 = 180 °FThe safety limit must comply with the requirements applicable in your country.

°F (°C) 212 (100)

Maximum operating pressure psi (bar) 44 (3)

Maximum time constant of thermostat and

manual reset high limit (STB)

s 40

Tab. 2 Technical specifications



2.9 Conditions for operationMaintaining the specified operating conditions will enable the boiler to provide a high level of reliability and long service life. Some details relate only to operation with Logamatic control panels from Buderus.

2.9.1 General operating conditions

Boiler type Unit GB125/22 BE GB125/30 BE GB125/35 BE

Boiler overall length (L) Inches 37 1/2" 42 3/8" 42 3/8"

Boiler block length (LK) Inches 25 3/4" 30 1/2" 30 1/2"

Combustion chamber length Inches 16" 20 1/2" 20 1/2"

Combustion chamber length Inches 10 5/8"

Burner door thickness Inches 2 1/3"

Distance between boiler feet (FL) Inches 16 1/8" 20 7/8" 20 7/8"

Net weight1) lbs 423 503 503

Tab. 3 Dimensions, weight and other data for boilers with burners1) Weight incl. packaging material approx. 6-8 % more.

CAUTION: Risk of system damage if operating conditions are not maintained.Extreme divergence from the stated conditions may cause irreversible damage to individual components of the boiler.

B The information on the rating plate is definitive.

Operating conditions

Min. boiler water tempera-

ture

Operating interruption

(complete boiler shutdown)

Heating zone with

heating zone mixing valve1) Min. return temperature

In combination with Logamatic control panel for variable low-temperature operating modes, such as Logamatic 2107.

No requirements. Operating

temperatures are safeguarded

by the Logamatic control

panel. 2)

Automatically by Logamatic control

panel

Not required but recommended with

low-temperature heating system design

130/113 °F.

Required with:

• Radiant floor heating system

• Systems with large water capacity:

> 115 gal/MBH

(1 MBH = 100,000 Btu/hr)

No requirements

Tab. 4 General operating conditions1) A heating zone with a mixing valve improves controllability and is specifically recommended for systems with several heating zones.

2) If the control panel does not influence the heating zones or a heating zone actuating component (e.g. Pumplogic), the burner ON mode must reach an operating temperature of 122 °F within 10 min by restricting volume flow.



2.9.2 Conditions for the boiler room and the environment

2.9.3 Fuel conditions

2.9.4 Power supply conditions

Operating conditions Notes – Requirement in greater detail

Temperature in the boiler room 40 to 104 °F

(5 to 40 °C)

Relative humidity max. 90 % No condensation or precipitation inside the boiler room

Dust/airborne particles − Excessive dust inside the boiler room must be avoided when the boiler is operat-

ing, e.g.:

• Dust from building work

Combustion air supplied from outside must not be excessively loaded with dust

or airborne seed; if necessary, air filters should be installed to prevent this:

• Air supply contaminated with dust from dirt roads and paths.

• Air supply contaminated with dust from production and processing facilities, e.g. quar-

ries, mines, etc.

• Airborne particles from thistles and similar

Halogenated-hydrocarbon com-

pounds

− The combustion air must be free from halogen-hydrocarbon compounds.

• Identify the source of halogen-hydrocarbon compounds and seal it off. Where this is

impossible, route combustion air from areas that are not contaminated by halogen-

hydrocarbon compounds.

Small animals − Prevent small animals from entering the boiler room, particularly through the air inlet vents –

by installing screens.

Fire safety − Maintain clearances between the boiler and flammable materials in accordance with local

regulations. A minimum clearance of 16” is required. Never store flammable materials or liq-

uids in the vicinity of the boiler.

Flooding − In case of an acute risk of flooding, disconnect the boiler in time from its fuel and power

supply before water enters the room. Any general and burner components or control equip-

ment that comes into contact with water must be replaced before starting up again.

Tab. 5 Boiler room and ambient conditions

Country All countries

Fuels #2 Fuel oil ASTM D396-05 Type 2

Approved for B5 Fuel Oil (5% biodiesel (B100) according ASTM D6751)

Remarks The burner may only be operated with the specified fuel.

Clean and service once a year. Check that the entire system functions properly at the same time. Immediately

remedy faults.

Tab. 6 Country-specific fuels and remarks


Line voltage 110 – 120 V The outer casing/boiler must be grounded to protect people and in order to function correctly.

Circuit breaker 10 A

Frequency 60 Hz

Protection class − IP 40 (protected against contact by entry of foreign objects > 0.04 inches Ø (> 1 mm Ø ), no

waterproofing)

Tab. 7 Power supply



2.9.5 Conditions for hydraulic system and water quality

2.10 DisposalB Dispose of boiler packaging in an environmentally-

responsible manner.B All heating system components that have to be

replaced should be disposed of in environmentally-responsible manner at an authorized disposal site.


Operating pressure (above atmo-

spheric)

15 – 44 psi

(1 to 3 bar)

Maximum 30 psi with the supplied safety valve.

Permissible test pressure 45 – 58 psi

(3 to 4 bar)

Safety temperature limitation by TR

temperature controller

122 – 194 °F

(50 to 90 °C)

Safety temperature limitation by man-

ual reset high limit (STB)

212 °F

(100 °C)

Water quality − The heating system may only be filled and topped up with water of domestic water qual-

ity. We recommend a pH level of 8.2 – 9.5.

Tab. 8 Hydraulics and water quality

3 Moving the boiler


3 Moving the boilerThis section details how to move the boiler safely.

3.1 Reducing the boiler weight for handling purposesIf required, you can reduce the weight of the boiler by removing the burner hood and door.B Unscrew the burner hood screws.B Lift burner hood slightly and pull forwards to remove.B Before removing the burner door: unplug the burner

plug from the burner controller.

Fig. 4 Removing burner hood

B Unscrew two hex bolts at the sides.B Open the boiler door.B Lift the burner door off its hinges.

Fig. 5 Removing the burner door

CAUTION: Risk of system damage from impact shocks!Fragile components could be damaged.

B Follow the transport instructions on the packaging.

Protect connectors against contamination if the boiler is not immediately put into operation.

Dispose of packaging in an environmentally-responsible manner.

Prevent the burner door from falling over and damaging the burner and burner tube.

7 747 019 141-04.1RS

3Moving the boiler


3.2 Lifting and carrying the boiler

The boiler can be held and carried at the grip positions shown (Fig. 6).B Unscrew the transit screws.

Fig. 6 Lifting and carrying the boiler

3.3 Moving the boiler with hand truck

Moving the boiler with hand truck (Fig. 7)B Place the hand truck (e.g. boiler trolley or sack truck) at

the back of the boiler.B Boiler, securing on the hand truck.B Move the boiler to the installation location.

Fig. 7 Moving the boiler with a boiler hand truck

The boiler is secured to the pallet by 2 screws for transportation purposes.

WARNING: Risk of injury from carrying heavy loads!B Always lift and move the equipment with

the assistance of another person using the grip positions shown.

7 747 019 141-05.1RS

WARNING: Risk of injury if load is inadequately secured during transportation!B Use suitable means of transportation, e.g.

the Buderus boiler hand truck with strap.B Secure the load against falling.

You can order the boiler hand truck from your Buderus distributor.

The boiler trolley can also be used to facilitate work on the underneath of the boiler, e.g. fitting the adjustable feet ( Chapter 4.3, page 16).

4 Placing the boiler


4 Placing the boilerThis section describes how to install and place the boiler in the boiler room.

4.1 Wall clearancesWherever possible, position the boiler with the recommended wall clearances. Reducing the minimum clearances makes the boiler more difficult to access.

The boiler base or foundation must be perfectly flat and level.

The burner door is factory-installed with the hinges on the right. The burner door can be converted to left-hand closing.

Fig. 8 Wall clearances in the boiler room (boiler positioned on the right-hand side)

CAUTION: Risk of system damage due to freezing!B Install the heating system in a frost-free

room.

Dimen-sion Wall clearance

A Recommended 40"Minimum 27"

B Recommended 27"Minimum 16"

C Recommended 28"Minimum 20"

D Recommended 16"Minimum 6"

L Chapter 2.8, page 8

Tab. 9 Recommended and minimum wall clearances (dimensions in inches).

The boilers are designed for a side clearance of 6".Where applicable, allow extra wall clearances for additional components such as DHW tank pipe connections, flue silencer, other flue components, etc.

WARNING: Risk of fire from flammable materials or liquids! B Clearances less than 6" must comply with

local and statutory codes.B Make sure that there is a sufficient

clearance between combustible materials and the chimney connection as specified by NFPA 31 (distance of 18 ").

B The floor must comply with the requirements of NFPA 31.

4Placing the boiler


4.2 Reversing the burner doorThe burner door is factory-installed with the hinges on the right – the burner door opens to the right. You can change the burner door hinges over to the left-hand side if required to suit the installation site.

Requirement: the burner hood must have been removed first ( Chapter 3.1, page 12).B Removing the burner door ( Chapter 3.1, page 12).B Unscrew the hex bolts [1] and remove the hinge pins

[2].B Fix the hinge pins [2] on the left-hand side of the boiler

using the hex bolts.

Fig. 9 Reversing the burner door (boiler block attachments)

1 Hex bolts2 Hinges

B Unscrew the hex bolts [1] and remove the hinge barrels [2].

B Fix the hinge barrels [2] on the left-hand side of the burner door [3] using the hex bolts.

B Hang the burner door [3] by locating the hinge barrels [2] on the hinge pins [4].

B Check that the heat exchanger baffles are placed horizontally ( Chapter 6.3, page 32).

B Close the burner door [3] and secure with the two hex bolts. Tighten the hex bolts evenly (approx. 90 lbs in) so that the burner door seals properly.

Fig. 10 Reversing the burner door (door attachments)

1 Hex bolts2 Hinge barrels3 Burner door4 Hinges5 Heat exchanger baffle plates

7 747 019 141-08.1RS

1 2 2 1

If the burner door hinges have been changed over to the left-hand side, the burner cable must be disconnected from the burner before opening the burner door.

7 747 019 141-09.1RS

1

4

5

23

4 Placing the boiler


4.3 Mounting the adjustable feet (included with B-kit)Level the boiler by turning the adjustable feet to prevent air pockets becoming trapped inside the boiler.

Requirement: the burner hood or burner door panel must have been removed first ( Chapter 3.1, page 12).

B Tilt the boiler with the aid of a hand truck or trolley ( Chapter 3.3, page 13) or place a wooden batten underneath to jack it up.

B Screw in adjustable feet [2] ¼ " – 1/8".B Gently set the boiler down.

Fig. 11 Fitting the adjustable feet(burner not shown)

1 Angle bracket2 Adjustable feet

4.4 Positioning and leveling the boilerB Position the boiler in its final location.B Level the boiler by rotating the adjustable feet as

required and using a level.

Fig. 12 Leveling the boiler

If the boiler is mounted on top of a horizontal hot water tank the adjustable feet are not used.

7 747 019 141-10.1RS

12

Protect boiler connections from damage and dirt if the boiler is not to be installed immediately.

7 747 019 141-11.1RS

5Installing the boiler


5 Installing the boilerThis section details how to install your boiler correctly. This involves the following steps:• Flue pipe installation• Providing air supply for combustion• Making the water connections• Making the electrical connections• Connecting the fuel supply

5.1 Flue pipe installationThe overall burner air supply/boiler flue pipe system conforms to the types of oil combustion equipment listed in the table below.

Observe the national standards and regulations for operating oil-fired appliances.

DANGER: Risk of fatal injury from toxic flue gases!B Never connect more than one boiler to a

flue system – regardless of whether the flue is vertical or horizontal.

B Common venting systems can cause damage to property and personal injury.

B Do not route the flue system through another flue system that is in use, e.g. a masonry chimney connected to a wood stove.

B Follow the instructions of the flue pipe manufacturer.

The boiler must be installed by a trained and certified installer in accordance with all requirements of NFPA-31, "Installation of Oil-Burning Equipment". Installation must comply with all local and national codes applicable to the installation of oil-fired boilers.

In Canada, the requirements of CSA/CGA-B139 Installation Code apply.

The GB125 boiler is approved for zero (0") clearance between its concentric vent pipe and combustibles.

Because of the tight construction of modern houses, this boiler must draw all air supply for combustion from outside (RLU).

Installa-tion type Combustion air supply and flue system

I or

HT-K

Concentric supply air and flue pipe exiting through external wall. Combustion air supply and flue systems are part of the combustion

equipment.II or

DO

Concentric supply air and flue gas routing via roof. Combustion air supply and flue sys-tems are part of the combustion equipment.

III or

GA-K

Concentric air/flue gas routing through a flue inside a duct. The space around the vent

pipe is used for combustion air.

Tab. 10 Types of installation

5 Installing the boiler


5.2 Test portsFlue gas readings and combustion air temperature readings are taken exclusively at the dedicated testing ports.

Follow the directions in the instructions for the Logatop BE oil burner.

Fig. 13 Installing the flue/air connector (included with the venting system)

1 Air intake test port2 Flue gas test port



Choice of installation site for side-wall flue terminationChoosing the right location for the terminal is critical to proper functioning of the appliance. As well as the minimum clearances ( Fig. 14), the following rules must be observed:

Fig. 14 Minimum clearances for side wall terminations

1. The termination should not face the prevailing wind direction.

2. The termination must be installed in such a way that the flue gases can disperse freely without re-entering the building.

3. The termination must be at least 2 ft from adjacent buildings and it must not be possible for the flue gas to enter adjacent buildings.

4. Where the building adjoins public walkways, the termination must be located at least 7 ft above ground. Make sure that freezing condensate does not constitute a hazard.

5. The termination must never be located below building overhangs, roof eaves, porches, enclosed spaces or lower parts of the building that could prevent unrestricted outflow of the flue gases.

6. The termination must never be located within 3 ft of inside corners of buildings and never less than 2 ft from outside corners of buildings.

7. If there is a fan-assisted air intake vent within 10 ft, the termination must be at least 3 ft above it.

8. The termination must be at least 4 ft below, 1 ft above or 4 ft horizontally from doors, windows or air inlet vents.

9. The termination must be at least 1 ft above ground and snow line, and protected from falling and accumulating snow, ice, leaves or debris.

10. The termination should be at least 3 ft from any type of building opening, oil tank filling or venting apparatus, and 6 ft from gas meters and similar equipment.

11. The position of the termination should be chosen so that the last horizontal section of pipe slopes downwards to the inside by ¼ " per ft. The flue terminal itself must also be inclined at ¼ " per ft to the inside so that any condensate drains inwards.

Concentricwall terminations on the house wall

at least 1 ft above grade and snow line

Concentric wall terminations on the house wall

Concentricwall terminations on the house wall

6 720 641 158-20.1TL

.

.

Forced Air InletGravity Air Inlet

must be at least 3 ft above forced air inlets within 10 ft.



5.3 Installation optionsThe GB125 boiler is approved with the following flue gas systems available from Buderus:

Table 12, page 21 shows the maximum permissible vent length for the different types of systems.

Types of installation Description

I or

HT-K

Concentric air supply and flue pipe exiting through external wall.

Horizontal direct vent concentric combustion air and venting pipe system.

II or

DO

Concentric supply air and flue gas routing via roof.

Vertical concentric supply air and flue gas routing.

III or

GA-K

Concentric air/flue gas routing through a flue inside a duct.

Flue pipe inside an existing masonry chimney similar to a liner. Chimney chase used as a raceway to bring in combustion air. Concentric supply air and flue gas routing from the chimney to the boiler.

Tab. 11 Installation options

To prevent reverse flow of flue gas into the air intake even with wind influence, the included wall terminations must be used.

Installation type III or GA-K may not be suitable for homes with a double flue chimney where the second flue is used with a second combustion appliance.



Pipe changes of directionThe overall lengths apply for systems with one elbow. Every additional elbow (accessory) reduces the maximum vent length by 3 ft (1 m).

Maximum length of flue pipe, feet (m)

Plastic flue system DN 80/125

Boiler capacity I or HT-KConcentric air sup-

ply and flue pipe exit-ing through external

wall

II or DOConcentric supply

air and flue gas rout-ing via roof

III or GA-KConcentric air/flue gas routing through a flue inside a duct

GB125 22 17’ (5.2 m) 51’ (17 m) 51’ (17 m)

30 17’ (5.2 m) 64’ (21 m) 64’ (21 m)

35 17’ (5.2 m) 71’ (23 m) 71’ (23 m)

Tab. 12 Maximum flue pipe lengths

For installation details see the Installation Instructions for the different flue gas systems.



5.4 Making the water connections

5.4.1 Installing B-kitThe safety valve and pressure/temperature gauge are installed into the supply manifold as described below:B Use the 1-1/4" BSP x NPT conversion nipple and

install the unmarked end into the supply (VK) connection of the boiler. This side also has longer thread length and the thread is straight (BSP).

B The conversion nipple is marked on the 1-1/4" NPT side with pink color and a NPT stamping in the pipe.

Fig. 15 Sealing the converter

B Seal 90° 1-1/4 NPT elbow on double nipple.B Mount conversion nipple on the elbow and align as

desired (Fig. 16).B Seal 90° elbow, safety valve and pressure/temperature

gauge.

Fig. 16 B-kit Installation

1 90° 1-¼" NPT elbow2 Double nipple3 Supply manifold4 Pressure/temperature gauge5 Safety valve6 90° ¾" NPT street elbow

CAUTION: Risk of system damage due to leaking connections!B Install hydraulic connections free of

tension on the boiler.

The safety valve can only be installed after the hydrostatic test (Chapter 5.5, page 24) has been completed. Use the supplied ¾" 90° elbow to ensure that the safety valve is installed horizontally.

We recommend installing a dirt filter (optional) in the boiler return connection to reduce build-up of debris on the water side.



5.4.2 Mounting the drain valve (included with B-kit)B Install and seal the drain valve on the EL connection.

Fig. 17 Installing the drain valve

RK Boiler returnEL Draining

5.4.3 Installation of system componentsSee the installation diagram for installation of the heating system components.

For more installation examples refer to Chapter 10, page 49.

Fig. 18 Installation diagram

1 Safety valve2 Pressure/temperature gauge3 Ball valve drain4 Air eliminator (in main supply)5 Heating pump6 Check valve (back flow preventer)7 Diaphragm expansion vessel8 Automatic feed valve9 Check valve (back flow preventer)10 Purge station11 Water supplyVK SupplyEL DrainingRK Boiler return

Install a drain valve in the return piping to the heating system.

7 747 019 141-15.1RS

RK EL

CAUTION: Risk of system faults from excessive flue gas temperature!B The drain valve connection (EL) must

never be used for any other purpose than to drain the boiler block.

For draining of the secondary heat exchanger system, install a boiler drain at the lowest point of the piping.



5.5 Filling the heating system and checking for leaksThe boiler is tested for leaks at the factory. Before putting the heating system into operation, it must be checked to ensure that no leaks will occur during operation.

Carry out the leak test at 1.5 times the normal operating pressure and in accordance with the local regulations.

B Seal off connection for safety valve ( Fig. 16, page 22) and all other unused connections with plugs.

B Isolate the expansion tank from the system by closing the valve.

B Open the mixing and shut-off valves on the heating water (primary) side.

B Slowly fill the boiler with tap water.

Fig. 19 Pressure/temperature gauge

CAUTION: Risk of system damage due to excess pressure when testing for leaks! Pressure, control and safety equipment may be damaged through excessive pressure.

B When you carry out a leakage test, make sure that no pressure, control or safety equipment that cannot be isolated from the boiler water chamber is installed.

CAUTION: Risk of damage to system due to temperature stress!If you fill the heating system when it is hot, the resulting temperature stress can cause stress cracks. The boiler will then leak.

B Only fill the heating system when cold (the supply temperature should be no more than 100 °F).

B Pay attention to the water quality as specified in the operator's log, and record the volume and quality of the water used to fill the system.

Maximumoperating pressure

Maximum test pressure

30 psi (2 bar) (with the included safety valve)

45 psi (3 bar)

Tab. 13 Maximum test pressure

7 747 019 141-17.1RS



B Bleed heat exchanger using the purge valve [1].B Slowly fill the heating system. Observe the pressure

gauge while filling.B Check the connections and piping to make sure they

are watertight.B Bleed the system via the radiator purge valves (if

applicable).B Top up with water if the pressure drops as a result of

bleeding the system.B Installing the safety valve ( Fig. 16, page 22).B When no leaks are found, remove pressure and

uninstall the plugs. Install safety valve and open valve to expansion vessel.

Fig. 20 Bleeding the heat exchanger system

1 Purge valve on the heat exchanger system

5.6 Connecting the fuel supplyB Install the oil line per local code.

The furnished Tigerloop oil filter must be installed on the outside of the boiler using the supplied mounting bracket.B Inspect the existing oil line and replace if necessary.

Check swing direction on burner door and reverse door swing if desired.

B Use the mounting bracket [7] as a drill template and drill 4 holes in the jacket panel.

B Secure the mounting bracket [7] to boiler side panel.B For a 3/8" oil line, install a 3/8" flare x 3/8" NPT adapter

[1] in the inlet and a 1/4" x 3/8" NPT adapter [2] between the oil filter [4] (Tigerloop) and the Firomatic valve [3].

B Install and seal the FiroMatic valve on the oil filter (Tigerloop) [4].

B Install the vacuum gauge in its adapter [6] and screw into the oil line feeding the burner.

B Connect the return oil line from the burner using the G 3/8" x 1/4" NPT adapter [5] back to the oil filter.

B Secure oil filter assembly to the mounting bracket.B Attach oil lines.B Check entire oil line assembly for leaks.

Fig. 21 Oil filter (Tigerloop)

1 Flare-NPT adapter (3/8" NPT)2 1/4" x 3/8" NPT adapter3 FiroMatic valve4 Oil filter (Tigerloop)5 NPT adapter (G 3/8" (60) x 1/4" NPT)6 Vacuum gauge7 Mounting bracket

5.7 Bleed off condensate

WARNING: Health risk from contaminated domestic water!B Always observe the regulations and

standards applicable in your jurisdiction for the prevention of contamination of drinking water (e.g. by water from heating systems).

Ensure that the siphon and piping are installed that fluids drain away freely, and backup into the boiler is prevented.



The boiler has the potential to produce significant amounts of condensate which must be drained and disposed of properly.

Follow all applicable codes and regulations covering the disposal of condensate originating from combustion appliances.• Ensure that untreated condensate is only passing

through hoses and piping suitable for very low pH levels.

• If the building is connected to a municipal sewage system, observe the rules and regulations for disposal into the system.

• If the building is connected to a septic system, a neutralizer is recommended to avoid damage to the system.

• Ensure the siphon is always filled with fluid to avoid unpleasant odors.

Installing and filling the siphon and neutralizerB Install the nut on the boiler condensate drain (Fig. 22,

[1]).B Install the o-ring on the boiler condensate drain pipe.B Merge the siphon with the boiler condensate drain and

tighten the nut [1].B Connect the drain hose [4] from the siphon [2] to the

neutralizer [5], and from there to the drain. Follow the instructions provided with the neutralizer [5].

B If fluid cannot be drained away by gravity, install a condensate pump.

B Fill the siphon with water through the service cover [3].

Fig. 22 Rear side of the boiler with siphon and neutralization

1 Condensate drain nut (boiler)2 Siphon3 Service cover (siphon)4 Drain hose (acid-resistant)5 Neutralizer

DANGER: Risk to life from flue gas poisoning!A dry siphon or leaky condensate connections can release flue gases into the building.B Check the siphon fluid level regularly and

fill with water if needed.



5.8 Electrical supply connectionsThis section only applies to boilers using Buderus control panels.

B To remove top rear boiler jacket, remove 2 mounting screws.

Fig. 23 Removing rear boiler cover and cover plate

5.8.1 Installing the control panelB Position the tabs [2] of the control panel in the slots [3].B Slide the control panel forward towards the burner

door.B Snap the flexible catches [1] into place in the knock-

outs provided [4].

Fig. 24 Installing the control panel

1 Flexible catches2 Tabs3 Slots4 Knock-outs

DANGER: Risk of fatal injury from electric shock!B Only qualified electricians are permitted to

carry out electrical work.B Before opening up the boiler, isolate it

completely from the line voltage and ensure the power cannot be inadvertently reconnected.

B Follow the installation instructions.

1

2

3

4

7 747 019 141-21.1RS



B Remove the top cover of the control panel. – Unscrew the cover screws [1].

B Secure the control panel with self-tapping screws [2].

Fig. 25 Removing the cover

1 Cover screws2 Self-tapping screws

5.8.2 Installing the temperature sensor assembly

B Feed the capillary tubes and the sensor lead [2] through the cable entry in the front boiler top panel [1] to the sensor well [3].

B Roll up surplus capillary tube and sensor lead length and place on top of the thermal insulation.

B Feed the burner cable [4] through the cable entry in the front boiler top panel [1] to the control panel.

B Connect the burner cable [4] to the control panel as indicated by the terminal markings.

Fig. 26 Routing and connecting cables

1 Cable entry in the front boiler cover2 Capillary tube and sensor cable3 Sensor well4 Burner cable

1

27 747 019 141-22.1RS

CAUTION: Risk of damage to system!Capillary tubes can get damaged from severe kinking or sharp burrs.

B Route capillary tubes carefully, avoiding bending them excessively



B Insert the temperature sensor assembly and balancing spring [3] in the sensor well [1] and push fully home. The plastic coil [2] is pushed back automatically.

B Push the sensor retaining clip [4] (supplied with the control panel) sideways onto the top of the well.

Fig. 27 Installing the temperature sensor assembly

1 Sensor well (measurement point)2 Plastic coil3 Balancing spring4 Sensor retaining clip

5.8.3 Power connection and connections of additional components

Establish a permanent connection to the main power connection in accordance with the locally applicable regulations.

B Route all cables through the cable entries above the thermal insulation to the control panel and connect in accordance with the wiring diagram ( Chapter 12, page 60).

B Remove blind connector from "Abgasüberwachung" Fig. 28.

B Insert flue gas manual reset high limit (STB) connectors in socket labeled "Abgasüberwachung" as shown in Fig. 29.

B Connect green burner plug in the socket labeled "Brenner".

Fig. 28 Routing the manual reset high limit and burner cables above the insulation to the control panel

Fig. 29 Connecting the manual reset high limit (STB) to the control panel

Ensure good contact between the sensor surfaces in the well [1] to ensure reliable heat conduction. Use the balancing spring [3].

1

1

4

2

3

7 747 019 141-24.1RS

WARNING: Fire hazard from hot boiler components!Hot boiler components may damage electrical cables

B Make sure that all cables are routed through the conduits provided or on the outside of the boiler's thermal insulation.

B Make sure the boiler is electrically grounded to NEC or CEC requirements.

The manual reset high limit (STB) arrives tripped and must be reset before commissioning.



5.8.4 Installing cable strain reliefSecure all cable runs with cable clips (included with the control panel):B Insert the cable clips together with the cable from the

top into the slots in the frame (step 1).B Slide the cable clips downward (step 2).B Push against the clips (step 3).B Flip the lever up (step 4).

Fig. 30 Securing cables with cable clips

5.9 Installing the back boiler coverB Place the control panel cover [1] in position and secure

with screws.B Install the rear boiler top panel [2].

Fig. 31 Installing the rear boiler cover

1 Control panel cover2 Rear boiler cover

7 747 019 141-25.1RS

6Starting up the heating system


6 Starting up the heating systemThis section describes the initial start-up procedure regardless of the installed control panel.

B Complete the commissioning report during this process ( Chapter 6.9, page 35).

Additional information on boiler room conditions and requirements, combustion air supply and flue systems and boiler operation can be found in Chapter 2.9, page 9.

6.1 Bringing the system up to operating pressureBring the system up to the normal operating pressure before commissioning.

B Top up the heating water or drain via the boiler fill and drain valve until the required operating pressure has been reached: minimum 15 psi, maximum 30 psi positive pressure (depending on safety valve installed).

B Bleed the heating system while filling.

Fig. 32 Pressure/temperature gauge for showing operating pressure and supply temperature

WARNING: Risk of boiler damage from excessive dust and air contamination!B Do not operate the boiler when there is

potential for a lot of dust being drawn into the combustion air supply.

B Install an air filter if the supply of combustion air contains large quantities of dust (e.g. from unpaved roads and tracks or dusty workplaces such as quarries, mines, etc.) or airborne particles.

CAUTION: Risk of damage to system due to material stress caused by temperature differentials!B Only fill the heating system when cold (the

flow temperature should be no more than 100 °F).

WARNING: Health risk from contaminated domestic water!B Observe all national standards and

regulations regarding prevention of domestic water contamination (e.g. by water from heating systems).

7 747 019 141-17.1RS

6 Starting up the heating system


6.2 Testing safety valveB Make sure that no people are in the discharge area of

the safety valve.B Raise the lever on the safety valve.

The safety valve must open and release pressure. If the safety valve fails to release excess pressure, it must be replaced, because otherwise system components may be damaged by excessive operating pressure.

6.3 Checking position of heat exchanger bafflesPrior to commissioning, check that the heat exchanger baffles are in a horizontal position:B Open burner door by removing the two hex bolts at the

sides.

B Slightly withdraw the heat exchanger baffles [1] from the heat exchanger.

B Adjust the heat exchanger baffles [1] to a horizontal position and push them back into the heat exchanger. Fig. 33 Opening the burner door

1 Flue gas baffles in the heat exchanger

B Close the burner door and secure with the two hex bolts (tighten to approx. 90 inch - lbs.). Tighten the hex bolts evenly so that the burner door seals properly.

6.4 Preparing the heating system for operationB Open the fuel supply at the main shut-off valve.B Switch on the heating system emergency shut-off

switch and/or the appropriate circuit breaker.

The GB125 comes equipped with 2 heat exchanger baffles at the lower position. Do not install additional heat exchanger baffles (Fig. 33).

1

7 747 019 141-27.1RS



6.5 Starting up the control panel and the burnerFor further start-up steps, follow the burner start-up sequence. Refer to the burner documentation for details.

Turn the control panel power switch to the "ON" position [2]. The burner starts up if the system is calling for heat or if you set the control panel to manual mode ( Control panel servicing instructions).B Select "Manual" mode .B Set the boiler-water temperature control [1] to the

desired temperature. Fig. 34 Switching on the control panel

1 Boiler aquastat2 On-off switch

6.6 Taking measurementsAllow burner to operate for 15 to 20 minutes before performing a combustion test. Earlier combustion tests can lead to incorrect readings as a result of burning off the sealant rope. We recommend rechecking the burner after a few weeks of operation.

Required instruments:• CO2 measuring equipment• Meter to measure draught• Oil pressure gauge 0-350 psi (25 bar)• Flue gas temperature sensor• Smoke tester

B Check the combustion chamber pressure at the pressure test port [1].

B Check draught via the test port on the combustion air intake/flue gas connections ( Fig. 13, page 18).

B Make all additional measurements according to the burner documentation.

Fig. 35 Pressure test port on burner door

1 Pressure test port

The manual reset high limit (STB) comes tripped and must be reset prior to start-up. To reset, unscrew cap on the side of the housing and depress green button. Replace cap.

AUT

190 160 140120

AUT

190 160 140120

1

2

6720641158.1TL

Incorrect burner adjustment can cause contamination of the boiler (e.g. soot). Faults may occur more often than normal.B Always check combustion with the

following instruments. B Never adjust burner visually.

1

7 747 019 141-29.1RS

6 Starting up the heating system


6.7 Checking the manual reset high limit (STB)The manual reset high limit interrupts the power supply if the maximum permissible flow temperature is exceeded.To enable a boiler reset and re-starting, the fault must be removed and the system must have fallen back below the limit.B Check the function of the manual reset high limit

( service instructions for the control panel).

6.8 Installing the burner hoodB Position the burner hood on the hooks on the boiler

outer casing.B Secure the burner hood with the two screws at the

sides.

Fig. 36 Installing the burner hood

DANGER: Risk of fatal injury from electric shock!B Only operate the boiler with the burner

hood installed.



6.9 Commissioning logB Initial and date the commissioning steps carried out.

Commissioning work Page Readings taken Comments

1. Fill heating system and check for leaks 24

____________ psi• Heating system filling pressure

2. Fill siphon with water

3. Bring the system up to operating pressure:

B Bleed heating systemB Test safety valveB Adjust the expansion vessel pressure

( expansion vessel documentation)

31

____________ psi

4. Check combustion air supply and flue system

5. Check position of heat exchanger baffles 32

6. Switch on the control panel ( control panel documentation) 33

7. Start up the burner ( burner documentation) 33

8. Check the manual reset high limit (STB) 34

9. Adjust the control panel settings to suit the customer's require-ments ( control panel documentation)

10. Inform operator, hand over technical documentation

Confirm properly-completed servicing Company stamp/signature/date

Tab. 14

Inform the customer about the correct fuel and correct operating pressure. Enter the details in the table ( boiler operating instructions).

7 Shutting down the heating system


7 Shutting down the heating system

7.1 Normal shut-downB With Buderus control panel: switch off the on/off

switch [1] on the control panel (position "0”). This switches off the boiler and all its components (e.g. burner).

Fig. 37 Switching off the heating system (Logamatic)

1 On-off switch

B Shut off fuel supply by closing main valve.

7.2 Shutting down the heating system in an emergency

7.2.1 Action in an emergencyExplain to the customer what to do in an emergency, e.g. a fire.

B Never put yourself at risk of fatal injury. Your own safety must always take the highest priority.

B Turn off the main isolating fuel valve.B Disconnect the heating system from the electrical

power supply by means of the emergency shut-off switch or the appropriate circuit breaker.

Fig. 38 Heating system emergency shut-off switch

CAUTION: Risk of system damage due to freezing!If the heating system has been switched off, it may freeze in cold weather conditions.

B Leave the heating system switched on as long as possible.

B Protect your system from freezing by draining the boiler, the heating system and hot water pipes at the lowest point.

AUT

190 160 140120

1

6720641158-34.1TL

Use the heating system emergency shut-off switch located outside the boiler room or the heating system circuit breaker for emergency shutdown.

8Heating system inspection


8 Heating system inspection

8.1 Why is regular maintenance important?Heating systems should be regularly maintained for the following reasons:

• to achieve a high level of efficiency and to operate the system economically (low fuel consumption),

• to achieve a high level of operational reliability,• to maintain the cleanest possible combustion,• to ensure reliable operation and a long service life.

Maintenance may only be carried out by a qualified service technician. If parts are replaced, only Buderus approved components may be used. Maintenance must be carried out once a year. The results of the inspection must be recorded in the inspection and maintenance log.

8.2 Preparing the boiler for inspection

B Shut down the heating system. ( Chapter 7.1, page 36)

B Remove burner hood from boiler. ( Chapter 3.1, page 12).

B Disconnect electrical power to burner.

Spare parts can be purchased from your Buderus distributor using the parts list (Chapter 11, "Spare parts," page 52).

DANGER: Risk of fatal injury from electric shock!B Before opening up the boiler,

isolate it completely from the mains power supply and ensure the power cannot be inadvertently reconnected.



8.3 Cleaning the boilerThe boiler can be cleaned with brushes and/or by a wet method. Cleaning equipment is available from your Buderus wholesaler.

B Open burner door by removing the two hex bolts on the sides.

8.3.1 Cleaning the boiler with cleaning brushesB Note the position of the heat exchanger baffles [1] for

later.B Remove the heat exchanger baffles [1] from the heat

exchanger.B Clean the heat exchanger baffles [1] with one of the

two cleaning brushes.

Fig. 39 Opening the burner door

1 Flue gas baffles in the heat exchanger

B Clean the hot gas passages by turning the round cleaning brush.

Fig. 40 Brushing out the hot gas flues

DANGER: Risk of fatal injury from escaping flue gases!B Follow these instructions carefully to

ensure safe operation of the system after completing the cleaning.

WARNING: Risk of burns from touching hot boiler parts!B Wear appropriate protective gloves or use

pliers.

1

7 747 019 141-27.1RS

7 747 019 141-37.1RS



B Clean the combustion chamber with a flat brush. Remove the debris from the combustion chamber, the hot gas flues and the flue connection.

B Reinstall the heat exchanger baffles in their original positions.

B Check sealant rope on burner door. Replace damaged or hardened sealant rope.

B Close the burner door and secure with the two hex bolts (tighten to approx. 90 lb ins). Tighten the hex bolts evenly.

Fig. 41 Brushing out the combustion chamber

B Seal the pressure testing nozzle for the combustion chamber pressure.

Re-commissioning after cleaning with brushesWhen the boiler is re-commissioned after cleaning with brushes, proceed as follows:

B Plug burner cable connector into burner.B With balanced flue operation, attach combustion air

hose to the burner.B Prepare the heating system for operation.

8.3.2 Wet cleaning (chemical cleaning)When wet cleaning, use a Buderus-approved cleaning agent appropriate for the degree of soiling (soot or scale). Follow the same sequence as described in Chapter 8.2, page 37 and Chapter 8.3, page 38.

B Cover the control panel with foil to prevent spray getting into the control panel.

B Spray cleaning agent evenly into the heat exchanger heater passages.

B Close burner door and start up the heating system.B Heat the boiler to a temperature of at least 160 °F.B Shut down the heating system.B Brush out the heat exchanger heater.B Start up the heating system again (see above).

You can obtain suitable sealant rope from your local Buderus wholesaler.

7 747 019 141-38.1RS

Follow the instructions for use of the cleaning agent. You may need to proceed differently from the method described here in some circumstances.

CAUTION: Risk of system damage from corrosion and short-circuit!B When wet cleaning protect electrical

components including the manual reset high limit (STB) from moisture and chemicals.



8.4 Cleaning the heat exchanger systemB Loosen the rear boiler cover [1].B Remove the thermal insulation [2].

Fig. 42 Opening up the heat exchanger system

1 Rear boiler cover2 Thermal insulation

B Undo the quick-release catches [1] for the cleaning access cover [2].

B Remove the cleaning access cover [2] and gasket from the heat exchanger system.

Fig. 43 Opening up the heat exchanger system

1 Quick-release catches2 Cleaning cover3 Thermal insulation

Only remove the strap around the bottom of the secondary condensing heat exchanger on the GB125/30 and 35 if instructed by a technician.



B Clean the inside of the heat exchanger system with plastic cleaning brush [1] (brush available separately).

B Vacuum out visible and loose combustion residue under the cleaning access cover.

B Check the gasket of the cleaning access cover and replace if damaged or hardened.

Fig. 44 Brushing out the heat exchanger system (viewed from above)

1 Plastic cleaning brush (accessory, part # 7747007899)

Wet cleaning can also be carried out in addition. Follow the same procedure as described for cleaning with the brush.

CAUTION: Risk of system damage due to use of incorrect brushes!B Use only the cleaning brushes suitable for

the heat exchanger system.

Avoid damaging the flue gas temperature sensor.

DANGER: Risk of fatal injury from escaping flue gases!B When reinstalling the cleaning access

cover, take care to ensure it is seated correctly and seals properly!

CAUTION: Risk of system damage from chemical cleaning agents!B When wet cleaning the heat exchanger,

use only water or cleaning agents approved by Buderus.

B Reinstall cleaning access cover and gasket.

B After completing cleaning, check any connections that were disconnected for leaks.

Follow the instructions for use of the cleaning agent. Under some circumstances you may have to proceed differently from the method described here.

CAUTION: Risk of system damage from corrosion and short-circuit!B When wet cleaning protect electrical

components including the manual reset high limit (STB) from moisture and chemicals.



Cleaning the condensate collector

B Open the condensate collector cleanout cover [1].B Remove condensate residues.B Securely replace the condensate collector cleanout

cover [1].

Fig. 45 Cleaning the condensate collector

1 Cleaning cover

8.5 Cleaning the neutralization and siphonThe procedure for cleaning the neutralizer unit is described in a separate instruction manual.

B Disconnect the condensate pipes from the siphon.B Remove deposits in the siphon and refill with water.B Reinstall the condensate pipes.

WARNING: Risk of injury from acid burning!The condensate in the condensate collector and the siphon can reach a pH level of 2.

B Always wear suitable clothing and protective goggles when cleaning.

DANGER: Risk to life from flue gas poisoning!A dry siphon or leaky condensate connections can release flue gases into the building.

B Check the siphon fluid level regularly and fill with water if needed.



8.6 Checking the air supply hose B Disconnect the corrugated hose [2] from the burner

intake silencer [3] by undoing the special hose clip [1] and check for dirt.

B If dirty, clean the corrugated hose [2] with a vacuum cleaner.

Fig. 46 Inspecting the corrugated hose

1 Special hose clip2 Corrugated hose (air supply for combustion)3 Intake silencer

8.7 Check heating system operating pressureThe system pressure for closed systems must be 15 – 30 psi (1.0 – 2.1 bar).

B Checking the operating pressure B If the pressure gauge shows less than 15 psi, the

operating pressure is too low. Add water to the system.

Fig. 47 Pressure/temperature gauge for showing operating pressure and supply temperature

CAUTION: Risk of system damage due to frequent topping up!If you have to top up the heating water frequently, the heating system may suffer damage from corrosion or scaling, depending on the water quality.

B Ensure that your heating system is bled properly.

B Check the heating system for leaks and proper operation of the expansion vessel.

WARNING: Health risk from contaminated domestic water!Observe all national standards and regulations regarding prevention of domestic water contamination (e.g. by water from heating systems).

7 747 019 141-17.1RS



B Add water through the fill valve.B Bleed the heating system.B Check the operating pressure again.

8.8 Test safety valveThe functioning of the safety valve must be checked at regular intervals (every 1 – 3 years depending on local regulations).

B Make sure that no persons are in the discharge area of the safety valve.

B Raise the lever on the safety valve.

The safety valve must open and release pressure. If the safety valve fails to release excess pressure, it must be replaced, because otherwise system components may be damaged by excessive operating pressure.

8.9 Concentric supply air and flue gas routing

B Check combustion air supply and flue gas routing for dirt and leaks. Measure CO/CO2 levels in boiler flue socket using annular gap method.

B Check that the condensate outlet is not blocked because, if it is, the condensate may run into the boiler and cause corrosion.

8.10 Air supply systemB If the CO2/CO levels are too high, check the air supply

system for blockages.

CAUTION: Risk of damage to system due to material stress caused by temperature differentials!B Only fill the system when cold (the flow

temperature at the temperature/pressure gauge should be no more than 100°°F).



8.11 Inspection and maintenance reportsB Initial and date the inspection operations completed. The inspection and maintenance logs can also be used as

copy masters.

Inspection work Page Date:______ Date:______ Date:______

1. Check general condition of the heating system

2. Visual inspection and function check of the heat-ing system

3. Check fuel and water-carrying components of the system for:

• Leaks during operation• Leak test• Visible signs of corrosion• Signs of aging

4. Check the combustion chamber and the heating surface for contamination; shut down the system for this step

36

5. Check heat exchanger system for:

• Dirt contamination• Damaged or hardened gaskets

40

6. Check burner ( burner documentation)7. Check combustion air supply and flue system for:

• Function and safety• Leaks• Blockages in the air supply system• In the case of a concentric combustion air sup-

ply and flue gas pipe, blockage of the conden-sate outlet

Clean the condensate pipeline and siphon8. Check the operating pressure, safety valve and

expansion tank inlet pressure43

9. Check function of DHW hot water tank and anode ( DHW hot water tank documentation)

10. Check control panel settings ( control panel documentation)

11. Record the final checks of the inspection work, incl. measurements and test resultsConfirm properly-completed servicing Company

stamp/signatureCompany stamp/signature

Company stamp/signature

Tab. 15 Inspection log book



Date:______ Date:______ Date:______ Date:______ Date:______ Date:______ Date:______

1.

2.

3.

4.

5.

6.7.

8.

9.

10.

11.

Company stamp/signa-ture







Tab. 16 Inspection log (continued)

If any condition requiring maintenance work is identified in the course of inspection, that work must be carried out as required.



Condition-based maintenance Page Date:______ Date:______ Date:______

1. Shut down the heating system 36

2. Remove and clean heat exchanger baffles 38

3. Clean the heat exchanger heater flue (heating surfaces) and combustion

chamber and afterwards reinstalling the heat exchanger baffles in original

positions

38

4. Check seals/sealant ropes on burner door and burner and replace as neces-

sary

38

5. Check and clean heat exchanger system, replace gaskets if necessary 38

6. Combustion air supply and flue system

• Clean air supply system

• In the case of concentric combustion air supply and flue pipe, clean the

condensate outlet

38

7. Start up the heating system 32

8. Carry out final check of the maintenance work

9. Check safe and proper operation

Confirm properly-completed servicing Company stamp/

signature

Company stamp/

signature

Company stamp/

signature

Tab. 17 Maintenance log book

Date:______ Date:______ Date:______ Date:______ Date:______ Date:______ Date:______

1.

2.

3.

4.

5.

6.

7.

8.

9.

Company stamp/

signature

Company stamp/

signature

Company stamp/

signature

Company stamp/

signature

Company stamp/

signature

Company stamp/

signature

Company stamp/

signature

Tab. 18 Maintenance log (continued)

9 Troubleshooting


9 TroubleshootingThere are two types of faults:• Burner faults and• Control panel and heating system faults.

If there is a burner fault, the fault indicator lamp on the burner comes on ( burner documentation). Such faults can generally be reset by pressing the reset button on the burner. Control panel and heating system faults are indicated on the control panel display if it has one. More detailed information can be found in the control panel documentation.

Correcting burner faults

B Press reset button on the burner [1].

Fig. 48 Resetting the burner

1 Reset button

CAUTION: Risk of system damage from pressing the reset button too frequently!Too many resets can damage the burner's ignition transformer.

B Do not press the reset button more than three times in a row.

B If the fault does not reset after the third attempt, try to localize and rectify the fault with the help of the burner documentation.

B Notify a service technician if necessary.

CAUTION: Risk of system damage due to freezing!The heating system can freeze up in cold weather if it has been disabled due to a fault shutdown.

B Rectify the fault immediately and restart the heating system.

B If this is not possible, protect your heating system against freezing by draining the boiler, the heating system and hot water pipes at the lowest point.

10Examples of installations


10 Examples of installations

Explanation of abbreviations

Fig. 49 Multiple zones with zone valves

1 Radiators

KR Return valve or check valve SH Heating zone adjuster mixing valve

DEV Diaphragm expansion vessel SV Safety valve air eliminator

PH Heating pump THV Thermostat

PW Hot water pump WH Water compensation pipe (diversion) bypass

PZ Recirculation pump

Tab. 19

DEV

10 Examples of installations


Fig. 50 Multiple heating circuits with heating pumps

1 Radiators

Fig. 51 Multiple heating zones with bypass for heating systems with large water capacity

1 Radiators2 Bypass boiler

DEV

DEV

10Examples of installations


Fig. 52 Multiple heating circuits with heating pumps and motorized mixing valve

1 Radiators

DEV

11 Spare parts


11 Spare partsThe following spare parts are available from Buderus. If there are several Buderus article numbers for one item number, the numbers for the various models are listed in the relevant columns.

Boiler block and burner door ( Fig. 53)

Spare parts with the article number 99 are not depicted in the graphic.

Item no.

DescriptionPart number

GB125/22 BE3 sections

G1B25/30 BE4 sections


1 Boiler block 3/4 sections V2 7747030522 774703524 774703524

2 Plug G1 1/4" right 86055310

3 Gasket D 41.7x55x1.5mm AFM 34, white 86159710

4 Stop plate with countersunk bolt, M8x16 63015342

5 Gasket D33x44x2mm 63005462

6 Plug G 1 05317712

7 Threaded rod M10x205 7747007599

8 Reducing nipple 3869828

9 Sensor well R3/4"x100mm 5446065

10 Tie rod set, M8x310mm 05127574 – –

10 Tie rod set, M8x440mm – 05127578

11 Heat exchanger baffle 3/4 sections 05347085 05347087 05347087

12 Angle bracket G125/4 GB125/3 everp 7747000019 – –

12 Angle bracket G124/5 GB125/4 everp – 7747000020

13 Hinge bracket G105/G115/G125 05327033

14 Appliance feet M10x51mm (set of 4) 05236440

15 Burner door GB125 7747022876

16 Hinge, painted 05327020

17 Inspection window seal assy. V3 63023634

18 Gasket 30x30x3 63014382

19 Glass pane 30x30x3.3mm 7747021876

20Heat insulation for burner door BE/non-Buderus rating 21/3-34/5

63002401

21 Sealant rope GB 14x1650 mm long 63020965

22Sealing compound, brown (310 ml cartridge) for gluing sealant rope

63014361

23 Infeed piece G11/4-28 GB125 V2 – 87185710550

23 Infeed piece G11/4-22 GB125 V2 7747030540 – –

Tab. 20 Boiler block and burner door

11Spare parts


24 Mounting material for boiler block G115/125 WS 63031288

25 O-ring 44x3 set (5 pieces) 7747031427

26 Pressure testing nozzle M6 SW 10 V2 63032101

99 B-Kit G115/G125 WS 63029762

Item no.

DescriptionPart number




Tab. 20 Boiler block and burner door

11 Spare parts


Fig. 53 Boiler block and burner door

7747102254.ab.RS-Kesselblock und Brennert r GB125 US

65

65

2

24

24 14

14

4

7

73

2

2424

2424

16

24

22

2416

15

20

1817

19

26

20

21

3

2424

2424 13

12

24

24

24

24

11

2523

1

85

9

10

10

2424

10

11Spare parts


Boiler outer casing ( Fig. 54)

Item no.

Description Part number




1 Burner hood GB125 63046609

2 Front thermal insulation 12x580x695 G115/G125 63025265

3 Appliance insignia Logano plus GB125 63045050

5 Cross-member 1.25x108x537 G115/G125 63029209

7 Side panel 565mm long 63029946 – –

7 Side panel 685mm long – 63029947

8 Thermal insulation GB125 WT top 7747012560

9 Boiler block insulation 3 sections G125 7747012582 – –

9 Boiler block insulation 4 sections G125 – 7747012583

11Spring clips for securing thermal insulation, pack of 10

7747016084

12 Front top panel assy. GB125 63029948

13 Hood rear compl. GB125, 3 sections 63029950 –

13 Hood rear compl. GB125, 4 sections – 63029951

16 Rear panel insulation GB125 7747012557

17 Cable clamp 07060754

18 Burner cable 2350 with cable grip 7747007984

19 Terminal block 7-pin green BR 7747023989

20 Connector plug ST18/ silver-plated 67903164

21Edge protector set 65+80+160Required for G125 RLU

63020896

23 Angle bracket GB125 rear panel 7747012473

24 Cable grommet G125 7747006779

25 Flat-head screw ST3.9x9.5 7747026999

26 Rear panel top 7747030545

27 Rear panel bottom 7747030544

28 Air hose Santo SLDN63 L1450 63024885

29 Corrugated hose clip 60/80 mm 63024917

30 Flue gas manual reset high limit STB complete 7747026825

31 Outer panel fixings G115, G125 63031847

32 Burner BE1.2/1.3-2.2/2.3 x x x

Tab. 21 Boiler casing

11 Spare parts


Fig. 54 Boiler casing

01

23

4

65

A

A

7747102255.ac.RS-Verkleidung GB125 US

13

12 31

25

24

29

28

29

31

8

16

30

11

31

7

31

31

32

19

31

31

312

1

3

3131

5

7

3121

18

20

17

31

31

31

31

9

23

27

26

11Spare parts


Heat exchanger WT (Fig. 55)

Item no.





1 H/E system 18-22 V2 87185702260 –

1 H/E system 30-35 V1 – 8718581224

3 Flue box cover 30-35 V1 – 8718579537

3 Flue box cover 18-22 V2 87185702210 –

4 Quick lock 07098848

5 KMVK sealant rope 1m 7747031485

6 Screw set GB125 7747013578

8 Gasket SHE 18-22 V2 87185702220 – –

8 Gasket SHE 30-35 V1 7747007464

9 Return pipe HK/WT G1-G1 V2 7747030543 – –

9 Return pipe HK/WT G11/4 V2 87185710540

10 Return pipe RK/WT G1-G1 V2 7747030541 – –

10 Return pipe RK/WT G11/4 V2 87185710530

11 Gasket D24x30.5 7747016507 – –

11 Gasket D27x38x2 7747031431

15 O-ring 21.89x2.62 EPDM 87185703570 – –

15 O-ring 28x3 70 EPDM 87185710570

16 Air vent 1/8 BSP 87161402380

17 Cover condensate tray 7747013577

18 O-ring 60x3 EPDM (3x) 7747007704

19 Lip seal DN80 PerOxyd set of 5 7747021733

20 Sensor bracket 07060986

21 Flue gas temperature sensor D29/d6 60lg 7747002902

22O-ring 6x2 ISO 3601 FKMSet of 3

7747007462

23 Siphon with float 7747020450

24 Inlet connection, siphon set GB125 7747019787

25 Extension G1 1/4x120 77471026385

26 Gasket D44x3 80427312

27 Extension G1x120 7747026384

28 O-ring 35x3 7747027431

Tab. 22 Heat exchanger WT

11 Spare parts


29 Siphon fixing bracket V2 7747030548

30 Pipe clip G125ECO/GB125 7747007705

31 Thermal insulation GB125 WT 18-22 kW 7747012558 –

31 Thermal insulation GB125 WT 30-35 kW – 7747012559

33Boiler adapter, concentric 80/125 GB125 V2(included with venting system)

7747016312

34 Gasket flue gas distributor 87185702200 8718579535

35 Spacer sleeve 17.2x2.1x68 87185702230

36 Spring clip d=32.6/22 7747030542 – –

36 Spring clip d=38.2/28 – 87185710560

37 Spring plug D26 7747030559

38 Spacer sleeve 17.2x2.1 87185708250

99 Siphon gasket set GB125 SB105 7747016504

Item no.





Tab. 22 Heat exchanger WT

11Spare parts


Fig. 55 Heat exchanger

6720905413.ab.RS-W rmetauscher GB125 18/3-35/4

29

30

31

5

25

35

35

28

159

11

1127

10

27

34

28

26

4

6

4

1

3

8

16

17

20

37

36

19

33

24

23

18

2221

38

12 Wiring diagrams


12 Wiring diagrams

Fig. 56 Wiring diagram

Index


Index

AAmbient conditions ....................................................... 10

BB-kit components ........................................................... 7B-kit Installation ............................................................ 22Boiler output .................................................................. 8Boiler type ..................................................................... 8Burner, notes on commissioning ..................................... 33

CCheck the manual reset high limit (STB)........................... 34Checking for leaks (heating water) .................................. 24Commissioning ............................................................ 31

log.......................................................................... 35Connecting power supply .............................................. 29Connecting the fuel supply............................................. 25Connections .................................................................. 8Correcting burner faults ................................................. 48

DDimensions.................................................................... 8Dirt trap....................................................................... 22

EExamples of Installations ................................................ 49

FFuel, operating conditions .............................................. 10

HHeat exchanger baffles, checking position........................ 32Heat exchanger baffles, removing.................................... 38Heat exchanger heater flue, cleaning ............................... 38Heating circuits, multiple................................................ 49Heating system emergency shut-off switch ....................... 36

IInstallation diagram ....................................................... 23Installation of drain valve ................................................ 23Installation room ........................................................... 10Installing outer casing panels.......................................... 30Installing strain relief...................................................... 30Installing the burner door jacket ...................................... 30Installing the control panel.............................................. 27Installing the temperature sensor assembly....................... 28

LLine voltage ................................................................. 10Log, commissioning ...................................................... 35Logs, inspection and maintenance .................................. 45

MMain power switch........................................................ 36Main shut-off valve ........................................................ 32Maintenance, regular ..................................................... 37

Mounting the adjustable feet .......................................... 16

OOn-off switch ............................................................... 36Operating conditions....................................................... 9

PPermissible operating pressure......................................... 8Power supply ............................................................... 10Pressure gauge/thermometer ................................... 31, 43Pressure test port ......................................................... 33

RRated heat output ........................................................... 8Removing burner door panel .......................................... 12Removing the boiler cover.............................................. 27Replacing sealant rope .................................................. 38Reversing boiler door .................................................... 15Reversing the burner door.............................................. 15

SSafety instructions .......................................................... 3Safety valve ..................................................... 22, 24, 32Scope of delivery............................................................ 7Shutting down.............................................................. 36Site test pressure ................................................... 11, 24Spare parts lists ........................................................... 52Supply temperature......................................................... 8

TTechnical specifications................................................... 8Thermometer/pressure gauge................................... 31, 43Topping up .................................................................. 43Transporting with boiler trolley/sack truck......................... 13Troubleshooting ........................................................... 48

WWall clearances............................................................ 14Water quality ............................................................... 11Wet cleaning ............................................................... 39


Notes


Notes

Documents

Installation and Oil condensing boiler Maintenance ... · 5.4.3 Installation of system components 23 5.5 Filling the heating system and checking for leaks 24 5.6 Connecting the fuel