INDIRECT FIRED, SEMI-INSTANTANEOUSSTEAM & BOILER WATER HEATER

Compact Design

High Recovery

Energy Efficient

Stainless Alloy Construction

Factory Packaged

Integral Safety System

ASME Constructed & Stamped

DHT VTSI & VSI SERIES

2

The DHT VTSI & VSI series of semi-instantaneous water heaters is the engineered solution where high recov-ery capacity is required and space is at a premium. The DHT VTSI & VSI series are constructed of stainless steel pipe and other non-ferrous materials to insure long leak-free operation. Designed for continuous high peak loads, the VTSI & VSI series are ideal for high demand applications such as hospitals or dormitories. Units are custom engineered using steam, boiler water or HTHW as the heating medium.

VTSI & VSI units are supplied as a complete packaged system with components engineered to specific appli-cation requirements. The user simply connects domestic water to the supply and return connections in the field. Use the DHT selection tables to select the correct size and match components for peak performance.

Semi-instantaneous operation provides high output by channeling the incoming cold water directly over the tubes of the heat exchanger in a controlled manner maximizing the heat transfer rates when compared to conventional stratified heat exchanger convection systems. Water is heated to the desired outlet temperature via the control valve as it exits the VTSI or VSI outlet. Velocity of water and pressure drop are controlled by changing water flow directly across the heat exchanger, which increases heat transfer and inhibits scale formation. High gain response is achieved by locating the temperature sensing probe in the outlet flow of water exiting the system thereby elimi-nating any stagnation zones which cause false readings.

DHT water heater systems are the perfect choice where high capacity is required and space is limited. The vertical configuration requires less than four square feet of floor space and the tube bundle can be removed straight out or downward from the bottom of the unit. No overhead space or extra clearances are required for service or maintenance. Horizontal configurations, with rack-mounted stands, are also available making the DHT VTSI & VSI series a perfect fit in any mechanical room.

APPLICATIONS

Commercial – VTSI & VSI series capacity ranges are well suited for meeting the large hot water demands of hotels, apartment buildings, military barracks and hospitals. Typically utilized in facilities with a central heating energy source, the units are perfect choices for installation in smaller satellite equipmentrooms. Units may be piped in parallel or series to provide additional capacity or emergency backup.

Institutional - VTSI & VSI series are widely used in facilities that exhibit high demand loads at vary-ing intervals throughout the day. Dormitories, schools and correctional complexes exhibit strong sudden demands that are difficult for conventional convection heaters to sustain. Smaller units may be combined with storage tanks to ease the energy source requirements during minimal use periods.

Industrial - VTSI & VSI series are used for high demand process applications that require a continuous flow of hot water. Other uses such as equipment food service wash down and cafeteria needs are also served by this versatile system.

Construction – DHT fabricates most units specifically to customer requirements. Stock systems are available for quick or emergency needs. All materials used in the construction of VTSI & VSI series systems are copper alloy or 316 stainless steel to assure long life and rust free domestic water. Each unit is fabricated by skilled technicians certified to ASME Sect IX, inspected, and stamped in accordance to ASME Sect VIII requirements. Working pressures up to 300 psig are available. The heat exchanger section is fabricated from copper, copper nickel or double wall tubes as well as 316 stainless steel for deionized water heating. Each heat transfer bundle is engineered to provide proper velocity and pressure drops while providing optimal heat transfer. The DHT VTSI & VSI series will provide exceptional long life, dependability and ease of maintenance. Seismic rated construction is available to meet IBC and other codes.

Water Heater Control Panel STANDARD FEATURES Microprocessor Based Two Line Alpha-Numeric 40 Character LCD Display3 Function KeysIsolated 24VDC Sensor Power 4/20MA1 Analog Input8 Digital Inputs1 Analog Output4 Relay Outputs 5 AMP. Fully User Programmable in English‘Pop Up’ Alarm Screens P.I.D. Setpoint Control RS485 MODBUS® Data PortCompatible with BMS/BAS

INPUT Temperature Set PointHigh Limit Temperature Set Points

OUTPUT PowerNormalHigh Temperature Alarm

Sizing DHT Semi-Instantaneous Water HeaterTo size DHT Semi-Instantaneous Water Heater you must determine the total water flow rate. First you have to determine total fixture units for

all fixtures by using hot water demand in fixture units tables, then determine the demand GPM of hot water from the chart below.

HOT WATER FLOW RATE CURVE

SEE ENLARGED DETAILON CHART AT RIGHT

200

400

600

800

1000

1200

1400

1600

1800

2000

2200

2400

2600

2800

3000 25 50 75 100

125

150

175

200

225

250

275

300

325

350

375

400

FIXTURE UNITS FIXTURE UNITS

HOT WATER DEMAND IN FIXTURE UNITS (140˚F WATER)

Sizing:Determine the total fixture units for all fix-tures by using the above table. Determine the required GPM from the above Hot wa-ter flow rate curve. Select the model of the water heater from Water heater selection chart according to the calculated GPM and the given steam pressure or boiler water temperature.

EXAMPLE:

Apartment building has 20 apartments: Bathtubs 1.5 x 20 = 30Dishwashers 1.5 x 20 = 30Kitchen Sinks 0.75 x 20 = 15Total 75 Demand from the curve above(Green color): 30 GPM

If steam pressure supplied to theBuilding 5 psig, the unit model is VTSIS24HB8A2-4-30, orVSISB8A2-4-30(USING CHARTS FOR TEMPERATURE RISE 40˚- 140˚ON PAGES 5 & 7. FOR BOILER WATER USE CHART ON PAGE 8)

RESTAURANTS

HOSPITALS, NURSING HOMES, NURSES RESIDENCE, APT. HOUSES, HOTELS & MOTELS

OFFICE BUILDINGS AND HIGH SCHOOLS

3

INPUT Temperature Set PointHigh Limit Temperature Set Points

OUTPUT PowerNormalHigh Temperature Alarm

DHT VTSI (TANK) SERIESDHT VTSI Series Semi-Instantaneous Water Heater Overall DimensionsHeating Source: STEAM

NOTE: Above dimensions are company’s standard model. For customers who wish to have a custom build, please consult with the engineering department. (Steam pilot shown, pneumatic and electric control available).

INSULATION &JACKETING

CONTROL BOX

WATER SOLENOIDT & P VALVE

PROBE & WELL

RECIRCULATION

B

D

F

CE

A

WATER OUTLET

STEAM INLET

STEAM STRAINERPILOT

CONTROL VALVEDRIP STRAINER

DRIP TRAPCONDENSATE

THERMOMETER

AQUASTAT

PRESSUREGAUGE

WATER INLET

RECIRCULATINGPUMP

CONDENSATE STRAINER

MAIN TRAP

4

51.0 48.0 40.0 50.0

52.0 49.0 48.0 52.0

57.0 54.0 54.0 57.0

58.0 55.0 59.0 59.0

VTSIS18HB6A2-X-XX

VTSIS24HB8A2-X-XX

VTSIS30HB10A2-X-XX

VTSIS30HB12A2-X-XX

DHT VTSI (Tank) Series Semi-Instantaneous Water Heater Selection Chart

NOTE: For performance rating greater or less then the table provided above, please consult with company’s engineeringdepartment for further details. For performance rating for units with double wall tubes please consult with company’sengineering department.

Heating Medium (Steam)Temperature Rise From 40 o-140oF

Steam Inlet Pressure (PSI) – Pressure in lines / Pressure in heat exchangerGPM

5/2 10/5 15/10 25/15 50/25

10

20

30

40

50

60

70

80

90

100

Heating Medium (Steam)Temperature Rise From 40 o-120oF

Steam Inlet Pressure (PSI) – Pressure in lines / Pressure in heat exchangerGPM

5/2 10/5 15/10 25/15 50/25

10

20

30

40

50

60

70

80

90

100

VTSIS18HB6A2-3-36 VTSIS18HB6A2-5-30 VTSIS18HB6A2-5-30 VTSIS18HB6A2-6-30 VTSIS18HB6A2-7-24

VTSIS24HB6A2-3-36 VTSIS24HB6A2-4-36 VTSIS24HB6A2-5-36 VTSIS24HB8A2-6-36 VTSIS18HB8A2-5-30

VTSIS24HB8A2-4-30 VTSIS24HB8A2-6-30 VTSIS24HB8A2-5-24 VTSIS24HB8A2-5-24 VTSIS24HB8A2-6-24

VTSIS24HB8A2-6-36 VTSIS24HB8A2-6-36 VTSIS24HB8A2-5-30 VTSIS24HB8A2-5-30 VTSIS24HB8A2-6-30

VTSIS24HB8A2-3-36 VTSIS24HB8A2-4-36 VTSIS24HB8A2-5-36 VTSIS24HB8A2-5-30 VTSIS24HB8A2-5-30

VTSIS30HB10A2-8-36 VTSIS30HB10A2-5-30 VTSIS30HB10A2-8-30 VTSIS30HB10A2-8-30 VTSIS30HB10A2-6-24

VTSIS30HB10A2-6-36 VTSIS30HB10A2-8-36 VTSIS30HB10A2-8-36 VTSIS30HB10A2-6-30 VTSIS30HB10A2-6-30

VTSIS30HB12A2-4-30 VTSIS30HB10A2-4-36 VTSIS30HB10A2-6-36 VTSIS30HB10A2-5-30 VTSIS30HB10A2-6-30

VTSIS30HB12A2-4-36 VTSIS30HB12A2-6-36 VTSIS30HB12A2-6-30 VTSIS30HB12A2-4-24 VTSIS30HB12A2-5-24

VTSIS30HB12A2-4-36 VTSIS30HB12A2-5-36 VTSIS30HB12A2-5-30 VTSIS30HB12A2-6-30 VTSIS30HB12A2-4-24

VTSIS18HB6A2-6-24 VTSIS18HB6A2-6-24 VTSIS18HB6A2-6-24 VTSIS18HB6A2-6-24 VTSIS18HB6A2-6-24

VTSIS24HB6A2-5-30 VTSIS24HB6A2-4-30 VTSIS24HB8A2-4-24 VTSIS24HB6A2-4-24 VTSIS18HB6A2-6-24

VTSIS24HB8A2-6-24 VTSIS24HB6A2-5-36 VTSIS24HB6A2-6-36 VTSIS24HB6A2-4-30 VTSIS24HB6A2-5-30

VTSIS24HB8A2-6-30 VTSIS24HB8A2-4-24 VTSIS24HB8A2-5-24 VTSIS24HB8A2-6-24 VTSIS24HB8A2-6-24

VTSIS24HB8A2-4-30 VTSIS24HB8A2-5-30 VTSIS24HB8A2-6-30 VTSIS24HB8A2-6-30 VTSIS24HB8A2-6-24

VTSIS30HB10A2-5-24 VTSIS30HB8A2-3.5-30 VTSIS30HB8A2-4-30 VTSIS30HB8A2-6-30 VTSIS24HB8A2-6-30

VTSIS30HB10A2-8-30 VTSIS30HB10A2-4-24 VTSIS30HB10A2-6-24 VTSIS30HB10A2-6-24 VTSIS30HB10A2-6-24

VTSIS30HB12A2-4-30 VTSIS30HB10A2-5-30 VTSIS30HB10A2-5-30 VTSIS30HB10A2-6-24 VTSIS30HB10A2-6-24

VTSIS30HB12A2-4-36 VTSIS30HB10A2-4-36 VTSIS30HB10A2-4-30 VTSIS30HB10A2-4-24 VTSIS30HB10A2-5-24

VTSIS30HB12A2-4-36 VTSIS30HB12A2-5-36 VTSIS30HB12A2-4-30 VTSIS30HB12A2-6-30 VTSIS30HB12A2-4-24

5

DHT VSI (VERTICAL) SERIES

DOMESTIC WATER OUTLET

L

CONDENSATE

DOMESTIC WATER INLET

STEAM

T & P RELIEF VALVE

THERMOMETER

WATER SOLENOIDVALVE

CONTROL PANEL

INSULATION & JACKET

I/P TRANSDUCER SHUTOFF SOLENOID VALVE

CONTROLVALVE

STEAM STRAINER

DRIP LEG THERMODYNAMIC TRAPWITH STRAINER

MAIN F & T TRAP

CONDENSATE STRAINER

TEMPERATURE TRANSMITTER OR

PROBECHECK VALVE

BALL VALVE

PUMP

Vertical Stand Configuration

DHT WATER HEATER SYSTEM DIMENSIONS (inches)(Vertical Configuration)

DHTModel Number OH OL H L

Width (notshown)

VSISB6A2-X-XX 79

7979

28VSISB8A2-X-XX 32VSISB10A2-X-XX 38VSISB12A2-X-XX 93 42

NOTE: Above dimensions are company's standard models. For customers who wish to have a custom build, please consult with the DHT Engineering Department. (Pneumatic control shown, pilot, and electric available)

38 24 23.7538 30 23.7538 30 23.75

40 34 25.75

6

DHT VSI Series Semi-Instantaneous Water Heater Selection ChartHeating Source: STEAM

DHT VSI (Vertical) Series Semi-Instantaneous Water Heater Selection Chart

NOTE: For performance rating greater or less then the table provided above, please consult with company’s engineeringdepartment for further details. For performance rating for units with double wall tubes please consult with company’sengineering department.

VSISB 6A2-6-24 VSISB 6A2-6-24 VSISB 6A2-6-24 VSISB 6A2-6-24 VSISB 6A2-6-24

VSISB 6A2-5-30 VSISB 6A2-4-30 VSISB 8A2-4-24 VSISB 6A2-4-24 VSISB 6A2-6-24

VSISB 8A2-6-24 VSISB 6A2-5-36 VSISB 6A2-6-36 VSISB 6A2-4-30 VSISB 6A2-5-30

VSISB 8A2-6-30 VSISB 8A2-4-24 VSISB 8A2-5-24 VSISB 8A2-6-24 VSISB 8A2-6-24

VSISB 8A2-4-30 VSISB 8A2-5-30 VSISB 8A2-6-30 VSISB 8A2-6-30 VSISB 8A2-6-24

VSISB 10A2-4-24 VSISB 8A2-3.5-30 VSISB 8A2-4-30 VSISB 8A2-6-30 VSIS 8A2-6-30

VSISB 10A2-8-30 VSISB 10A2-4-24 VSISB 10A2-6-24 VSISB 10A2-6-24 VSISB 10A2-6-24

VSISB 12A2-4-30 VSISB 10A2-6-30 VSISB 10A2-5-30 VSISB 10A2-6-24 VSISB 10A2-6-24

VSISB 12A2-4-36 VSISB 10A2-4-36 VSISB 10A2-4-30 VSISB 10A2-4-24 VSISB 10A2-5-24

VSISB 12A2-4-36 VSISB 12A2-5-36 VSISB 12A2-4-30 VSISB 12A2-6-30 VSISB 12A2-4-24

VSISB6A2-3-36 VSISB6A2-5-30 VSISB6A2-5-30 VSISB6A2-6-30 VSISB6A2-7-24

VSISB6A2-3-36 VSIS6A2-4-36 VSISB6A2-5-36 VSISB8A2-6-36 VSISB8A2-5-30

VSISB8A2-4-30 VSISB8A2-6-30 VSISB8A2-5-24 VSISB8A2-5-24 VSISB8A2-6-24

VSISB8A2-6-36 VSISB8A2-6-36 VSISB8A2-5-30 VSISB8A2-5-30 VSISB8A2-6-30

VSISB8A2-3-36 VSISB8A2-4-36 VSISB8A2-5-36 VSISB8A2-5-30 VSISB8A2-5-30

VSISB10A2-8-36 VSISB10A2-5-30 VSISB10A2-8-30 VSISB10A2-8-30 VSISB10A2-6-24

VSISB10A2-6-36 VSISB10A2-8-36 VSISB10A2-8-36 VSISB10A2-5-30 VSISB10A2-6-30

VSISB12A2-4-30 VSISB10A2-4-36 VSISB10A2-6-36 VSISB10A2-5-30 VSISB10A2-6-30

VSISB12A2-4-36 VSISB12A2-6-36 VSISB12A2-6-30 VSISB12A2-4-24 VSISB12A2-5-24

VSISB12A2-4-36 VSISB12A2-5-36 VSISB12A2-5-30 VSISB12A2-6-30 VSISB12A2-4-24

7

DHT VSI (VERTICAL) SERIES

DOMESTIC WATER OUTLET

DOMESTIC WATER INLET

T & P RELIEF VALVE

THERMOMETER

CONTROL PANEL

INSULATION & JACKET

TWO OR THREEWAY WATERCONTROL VALVE

BOILER OR HTHWINLET

BOILEROR HTHW

OUTLET

I/P TRANSDUCER

SHUTOFF SOLENOIDVALVE

TEMPERATURE TRANSMITTER OR

PROBE

CHECK VALVE

BALL VALVE

PUMP

OH

H

L

OL

WATER SOLENOIDVALVE

Vertical Stand Configuration

DHT WATER HEATER SYSTEM DIMENSIONS (inches)(Vertical Configuration)

DHTModel Number OH OL H L

Width (notshown)

VSISW6A2-X-XX 88

8888

28VSISW8A2-X-XX 32VSISW10A2-X-XX 38VSISW12A2-X-XX 96 42

NOTE: Above dimensions are company's standard models. For customers who wish to have a custom build, please consult with the DHT Engineering Department. (Pneumatic control shown, pilot, and electric available)

42 24 23.7542 30 23.7542 30 23.75

42 34 25.75

8

DHT VSI Series Semi-Instantaneous Water Heater Selection ChartHeating Source: BOILER WATER

DHT VSI Series Semi-Instantaneous Water Heater Selection ChartHeating Source: BOILER WATER

VSIW8A2-2-40VSIW10A2-4-36VSIW10A2-3-36VSIW10A2-2.5-40VSIW10A2-2.5-40VSIW12A2-2-36VSIW12A2-2.5-40VSIW12A2-2.5-42VSIW12A2-4-48VSIW12A2-2.5-48VSIW14A2-4-48

5176

102128153204255306357409511

VSIW6A2-2-36VSIW8A2-2.5-36VSIW8A2-4-40VSIW10A2-4-30VSIW10A2-2.-30VSIW10A2-6-36VSIW10A2-4-38VSIW10A2-3-40VSIW12A2-4-36VSIW12A2-4-36VSIW12A2-4-36

500,000750,0001,000,0001,250,0001,500,0002,000,0002,500,0003,000,0003,500,0004,000,0005,000,000

NOTE: For performance rating greater or less then the table provided above, please consult with company’s engineeringdepartment for further details. For performance rating for units with double wall tubes please consult with company’sengineering department.

VSIW6A2-2.5-40VSIW8A2-4-36VSIW8A2-2.5-36VSIW8A2-2.5-40VSIW10A2-4-30VSIW10A2-4-36VSIW10A2-4-36VSIW10A2-2.5-36VSIW10A2-4-40VSIW10A2-2.5-40VSIW12A2-2.5-36VSIW12A2-2.5-38

VSIW6A2-2.5-36VSIW6A2-2.5-36VSIW8A2-4-30VSIW8A2-2.5-30VSIW8A2-2.5-30VSIW10A2-2.5-24VSIW10A2-4-30VSIW10A2-4-30VSIW10A2-4-30VSIW10A2-4-38VSIW10A2-4-30VSIW10A2-4-30

9

Double-Wall Tube Bundles for Water Heaters

Meets Uniform Plumbing Code requirements for heating potable water. Prevents cross-contamination.

• Easy Inspections and low maintenance

• Fully visible, 360˚ vented leak detection between tubesheets.

• Bolting and gaskets for potable water and heating medium are completely independent.

• Individual tube access for easy maintenance.

• Optional: Tubesheet contacting potable water is solid 304 stainless steel

• Used to upgrade present single-wall tube bundles

• Available semi-instantaneous water heaters and exchangers with copper or cupro-nickel tubes and carbon steel or

stainless steel tube sheets (Up to 400 PSIG with. cupro-nickel tubes)

Double Wall Protection Performance

Tube failure can be caused by corrosion, erosion, and vibration, and can result in the contamination of the domestic water system to be contaminated by a heating medium such as steam, hydronic water, glycol solution, etc. There is no practical way to have the heating medium sterile or free from harmful treatment compounds or corrosion by-products. A low pres-sure heating medium circuit does not ensure contamination protection of indirect, single-wall water heaters. Whether they are shell and tube, shell and coil, plate and frame, or any other type, all consist of relatively thin wall heat transfer surface separating the heating medium from the domestic water system. Therefore, the potential for cross contamination is real and in some instances contamination has occured. Several states and cities are now insisting on double-wall vented construction in all indirect type domestic water heaters. Plumbing codes have also been re-written to include double-wall protection. DHT has developed the most practical, “state-of-the-art” double tube wall heaters to preclude any possibility of contaminating the domestic water system.

The heat transfer surface is 5/8” O.D. x .04” thick inner wall and 3/4” O.D. x .04”outer wall SB-75 or SB-111 copper tubing. The .04” dimensions are actual net tube wall thicknesses which equal .08” thickness of total wall separation. This is more than twice the thickness of many single wall water heater products. Both inside and outside tube surfaces are smooth (prime) with no fins or surface irregularities to promote scale formation or corrosion attack.

Double-wall tubing has a similar overall heat conductivity as a single wall tube of equivalent wall thickness. The heat trans-fer capabilities were determined by actual tests. Each tube has multiple parallel and continuous vent paths.

10

DHT VTSI & VSI SERIES

Drip Strainer

Control Valve withSafety Solenoid

3-Way - Optional

DHT stainless steel semi-instantaneous water heater system is a very efficient, high quality and high capacity system for use with steam, boiler water, or high temperature water as a heating medium. DHT steam-water heater system has a small compact size and a wide range of capacities that are designed for many standard hot water applications. DHT’s compact design makes it an ideal replacement unit where space is at a premium. Also the compact design and size reduces the installation time to the minimum. The customers only need to provide the connection line for cold and hot water, steam, condensate and electricity to service. DHT’s stainless steel semi-instantaneous water heater system provides both designer flexibility and space saving design.

Standard DHT Stainless Steel Semi-Instantaneous Water Heater System

Material of Construction

• Coil Material: Standard - - - - - Copper Optional - - - - - -Cupro-Nickel Optional - - - - - -Stainless Steel Optional - - - - - -Double Wall Copper or Cupro-Nickel

• Shell - - - - - - - - - - - - - - - - - - - - - - - - High Alloy Stainless Steel• Piping - - - - - - - - - - - - - - - - - - - - - - - Copper, Brass• Insulation - - - - - - - - - - - - - - - - - - - - Fiberglass• Protection Jacket - - - - - - - - - - - - - - -20 Gauge Steel/Vinyl• Support Skid - - - - - - - - - - - - - - - - - - Carbon Steel

OPTIONAL:1. Electric Control Box2. Recirculator Package3. Double Solenoid Safety System

Standard DHT Stainless Steel Steam or Boiler Water Heater System Package Includes:

• Compact Design• A.S.M.E.CODE Construction (225 PSIG of water pressure at 300˚)• High Alloy Stainless Steel Tanks/Shells• High Alloy Stainless Steel Threaded Connections (domestic water only)• Fiberglass Insulation• 20 Gauge Steel Jacket• Carbon Steel Support Base• A.S.M.E Relief Valve-Pressure and Temperature• Temperature gage• Pressure Gauge• Drain Valve• Solenoid Safety System • Temperature Control Valve (self conatined or pneumatic)• Steam, Condensate Strainers (steam only)• F&T Traps (steam only)

Stainless Steel Semi-Instantaneous Steam-Water Heating Systems

11

12

Steam Water Heater Single Unit

T/

PCondensate Return

Steam Supply

Hot Water O

ut

Recirculation

Cold Water InTo Drain

Drain

Condensate to Gravity

Free Drain or to Pump

to Lift

T/

P

/

P

T

Steam Water Heater Dual Unit

DHT VTSI & VSI SERIES (PIPING LAYOUTS)

Boiler Water Heater Single Unit

T/

PCondensate Return

Steam Supply

Hot Water Supply

Recirculation

Cold Water InTo Drain

Drain

Hot Water Return

Storage Tank

To Drain

Hot Water Out

Condensate to Gravity

Free Drain or to Pump

to Lift

/

Boiler Water Return

Boiler Water Supply

Recirculation

Cold Water In

To Drain

Drain

Hot waterOutlet

T

Steam Water Heater Single Unit with Storage Tank

13

Specifications for DHT Water HeaterEach heater shall be capable of being disassembled and the heat exchanger section removed for inspection and service without breaking water connections. The bolting between the steam bonnet, tube sheet and shell flange shall be independent of each gasket to allow inspection and replacement of either gasket without disturbing the other gaskets. Each heater shall have easy access to the individual tubes without moving the heater from its installed position.

Steam to WaterFurnish and install where shown on the plans ___________________water heater(s), Model Number __________ , manufactured by Diversified Heat Transfer, Inc.

Each heater shall be factory assembled package rated to heat ____________.gpm of water from _______°F to °F and control the outlet within 4°F of the selected temperature, when supplied with __________________psig saturated steam before the control valve. The domestic water pressure drop through the heater shall not exceed __________________psig.

Each heater shall be constructed and stamped in accordance with Section VIII of the ASME Code for a working pressure of 150 psig. Inspection form U -1 shall be furnished.

Each packaged heater shall consist of the following components completely factory assembled so that the contractor need only connect to service.

1. Water heater with stainless steel shell and heat exchanger wrapper, copper or Cu-Ni tubes, non ferrous or carbon steel with non-ferros liner tube sheet and baffles, carbon steel steam chamber, steel vertical support skids and lifting lug.

2. Steam strainer.3. Temperature control valve (___________pilot operated or _______air operated). 4. Condensate strainer. 5. Main steam trap. 6. Auxiliary steam trap.7. Water thermometer and steam pressure gauge. Thermometer installed with separable thermowell.8. ASME pressure relief valve for domestic water.9. Insulation: 1-1/2” fiberglass covered with a galvanized steel or plastic gasket.10. Bronze circulator – 115 volt/60 cycle/single phase, wired for continuous operation. (Optional____Yes, ___No)11. Component piping.12. Solenoid Safety System (___Single, ___Double)13. Electric Control Box (Optional____Yes, ___No)14. Installation and operating instructions.

The manufacturer shall assume the operational responsibility for all components of the package.

Water to WaterFurnish and install where shown on the plans ___________________water heater(s), Model Number __________ , manufactured by Diversified Heat Transfer, Inc.

Each heater shall be factory assembled package rated to heat ____________.gpm of water from _______°F to °F and control the outlet within 4°F of the selected temperature, when supplied with __________________boiler water. The domestic water pressure drop through the heater shall not exceed __________________psig.

Each heater shall be constructed and stamped in accordance with Section VIII of the ASME Code for a working pressure of 150 psig. Inspection form U -1 shall be furnished.

Each packaged heater shall consist of the following components completely factory assembled so that the contractor need only connect to service.

1. Water heater with stainless steel shell and heat exchanger wrapper, copper or Cu-Ni tubes, non ferrous or carbon steel with non-ferros liner tube sheet and baffles, carbon steel steam chamber, steel vertical support skids and lifting lug. 2. Temperature control valve (___________pilot operated or _______ air operated). 3. Water thermometer and steam boiler water pressure gauge. Thermometer installed with separable thermowell. 4. ASME pressure relief valve for domestic water. 5. Insulation: 1-1/2” fiberglass covered with a galvanized steel or plastic jacket. 6. Bronze circulator - 115 volt/60 cycle/single phase, wired for continuous operation. (Optional____Yes, ___No)7. Component piping. 8. Solenoid Safety System (___Single, ___Double)9. Electric Control Box (Optional____Yes, ___No)10. Installation and operating instructions.

The manufacturer shall assume the operational responsibility for all components of the package.

INDIRECT FIREDSEMI-INSTANTANEOUSSTEAM & WATER HEATER

www.dhtnet.com • www.dhtcoils.com Tel: 1-800-221-1522

Manufacturers and Designers Since 1938.Pub DHT03R1 12/15