Heating Systems - vusite.net · 2 Heating Systems Boiler Controls 2 3 ... back-end protection ... or use relay logic interlocks but note that the fan status cannot

HeatingSystems

2

2 2 Heating Systems Boiler Controls

2 Heating SystemsBoiler Controls 2 3

Primary Pumps 2 6Boiler Control - No Housekeeping 2 7Modulating Boilers 2 8Boiler Status Monitoring 2 9Additional Status Monitoring 2 10Flue Dilution Fans 2 11

Secondary Circuits 2 13Sub Zones 2 21

Domestic Hot Water Control 2 25

Direct Space Heating 2 31

Examples Wet Heating1 2 Boilers, 1 Zone 2 332 Multiple Boilers, Multiple Zones 2 393 Multiple Boilers, Multiple CT Circuits 2 45

Boiler ControlsBoilers are controlled by a Boiler Controller. It may contain theSystem Housekeeping Function - see Section 7. Two types of Boiler Controller are available, each with versionsfor Auto Duty Rotation or Fixed Sequencing, and with/without Housekeeping. Boilers are Demand Driven from connected loads; you will need at least one Zone Controller to make the Boilers run.

For twinPumpsets useChangeoverSubmodule

Sensors - must fit one ofFlow and Return Temperature

How many stages?Add Cascade Module ifmore than 2 Stages

Boiler Controller

Boiler Typeselect Single Stageor Hi/Lo Fired

Basic Boiler Control

Boiler Controller controls 2 Boilers or Boiler stages1 Primary pump & 1 VT circuit Valve and Pump

Heating Systems Boiler Controls 2 3


Boiler Types•Single-stage Boilers, use BLR/DIN/STD/...

•2-stage (Hi/Lo fired)Boilers, use BLR/DIN/HIL/...

•Condensing Boiler, as lead boiler use a fixed sequence variant BLR/DIN/.../003 or 006

•MTHW Boilers, contact SeaChange for special order code

•Modulating Boilers see page 2 8

Sensors •One Flow OR Return sensor must be fitted

•Flow AND return sensors fitted allows better control and back-end protection

•Control from flow, return or average by setting SACT parameter

•Outside sensor must be fitted if this is the System Housekeeping module

•Status input can be used to generate System Stop Alarm which will shut down items of plant. Select using ALRM parameter in Boiler Controller to send STOP alarm. Set ALRM parameter in other modules to respond to STOP alarm

•Additional Status Monitoring see page 2 10

MultiStages•Boiler Controller can control 2 stages i.e. 1x Hi/Lo fired

boiler or 2x single stage boilers

•Cascade Submodule provides additional 2 Boiler stages usingCAS/DIN/3T/001

•Cascade Submodule works with any type of Boiler Controller

•up to 8 Boiler stages maximum

Fault /Lockout•Boiler Controller and Cascade submodule have 2 status

inputs for monitoring or alarm. The inputs must be Volt-Free contacts.

• Status inputs can be used for general plant status monitoringand can generate alarms

•Status inputs can be used for boiler lockout signals or stage disable switches

Automatic Pump Changeover by usingChangeover submodulesfor Primary or VT Pumpsets

Boilers run when HeatDemands from other modulesrequire Up to 3 Cascade Modules allow up to

8 Single Stage Boilers or 4 Hi-Lo Boilers to be controlled

type /001Primary Pumps

type /002VT Pumps

Boiler Controlusing submodules

The functionality of the Boiler Controller can beextended by Cascade Submodules to add Boilers andby Changeover submodules to add Pump Changeover.


Primary PumpsSingle Pumpset

•Boiler Controller has an output for Primary Pump.

•Pump runs when Boilers run, run-on facility using BRON parameter

Shunt Pumps•for shunt pumps per stage and back-end valves, use panel

interlocksTwin Pumpset

•use Changeover Submodule PCO/DIN/3T/001

• ignore output on Boiler Controller, wire pump enables from PCO submodule

•PCO Submodule will need status (not trip) signal from flow switch or contactor auxiliary, either 1 signal per pump or 1 per pump pair

•PCO will energise duty pump when commanded by the Boiler Controller

•Duty changeover occurs every time pumpset starts, or after an adjustable Hours-Run period, or on Duty Pump failure

•Pump Exercise Routine can be enabled. Set Parameter MXDYto number of days without running before pump is exercised for MNON Period Default 2 MinutesThis is a feature of all Changeover submodulesSet MXDY=0 (Default) to disable this feature.So set MXDY=7 and MNON=10 to exercise the lead pump for 10 minutes if they have not run under control for 7 daysThe other pump will run when the unit next runs

VT Circuit Control•Boiler Controller has secondary circuit. See Secondary

Circuit section 2 13 for description of operation


Heating Systems Boilers 2 7

Boiler Controller - No Housekeeping•The Boiler Controller is available with or without the

Housekeeping function

•The Boiler with Housekeeping can support:3 Boiler Cascades OR Actuators2 Pump ChangeoverNote in special applications these numbers can be exceededbut no more Boiler or Pump stages are controlled see 2 9 and2 11

•The Boiler Controller No Housekeeping was formerly called the ‘Secondary Boiler Controller’

•The Boiler without Housekeeping BLR/DIN/NH/STD/ can only support 3 submodules:

2 Boiler Cascades OR Actuators1 Pump Changeover

If you require pump changeover on the VT circuit then use a separate secondary circuit controller with its own PCO module registered to it

Boiler Controller No Housekeeping

for Primary PumpsPCO/DIN/3T/001

only 2 Cascade Modules

for Secondary PumpsPCO/DIN/3T/004

for VT Circuitif PumpChangeoverrequired

Boiler - No Housekeeping can have 1 Changeover Module and 2 Cascade Modules.Use separate Secondary Circuit Controller andChangeover submodule for dual VT pump systems.

Modulating Boilers•2 Modulating Boilers can be driven using a combination of

the standard Boiler Controller and an analogue output Actuator Controller Submodule. The Boiler Controller outputs are used to enable the Boilers. The Actuator Controller has two 0-10V outputs to modulate the output of the boilers.

•Use Boiler without Auto Rotation type BLR/DIN/STD/003

•Pump Changeover submodules can be used with the Boiler Controller in the standard way

Actuator ControllerACT/DIN/AOP/722

Boiler Enable0-10V BurnerModulation

Boiler ControllerBLR/DIN/STD/...

Using Actuator Controllerfor modulating boilers

ACT/DIN/AOP/722

ModulatingBoilers



Boiler Status MonitoringAdditional status inputs using All Remote Feature

The boiler module has two status inputs that can be used for either General Alarm or Status inputs eg:

Pressurisation UnitGas ValveFire AlarmThermal Link

or for Boiler Status/Lockout, but not both.

To use both General Alarm and Boiler Status use the All Remote Feature of the Boiler. Set AREM = 1 in Boiler moduleThe Boiler outputs on the Boiler module are disabledand only the outputs on Cascade modules are enabled. The inputs on the Cascade submodules are used for Boiler Status/Lockout and the Boiler module inputs for GeneralAlarm inputs.

With All Remote operational, 4 Cascade Modules can be used so that 8 boilers or stages can be controlled.

Boilers

All Remote feature allows all Boiler Status and General Plant Alarms to be monitored

GeneralPlantAlarms

BoilerStatusInputs

BoilerCascadesubmodules

Plant Status Monitoring

Additional Status MonitoringThe Boiler modules two Status/Alarm inputs can be used to monitor General Plant Alarms.

If more than two alarms are needed then they are normally wired to provide a single common alarm input. This will drive the plant satisfactorily but it will not be possible to view the individual plant status inputs from the Doorway Supervisor. It is possible to use the Monitoring Module to provide individualalarm inputs.

The relay outputs of the Monitoring Module track the input status. The relays can be wired to produce a common alarm/status input to the Boiler module.

General PlantAlarms e.g.pressurisation unit

gas valvefire alarm

thermal linkknock off

Relay output provides common Alarm/Status output

Common GeneralPlant alarm input to

Using Monitoring Module to allow individual General Plant Alarms to be viewable from Doorway

Additional Alarm Inputs to Boiler Controller


Flue Dilution Fanswith Changeover submodule

Flue Dilution Fans can be controlled by using a Changeover submodule registered to the boiler. This will control a changeover pair of fans with one or two flow status inputs.

If a fan fail is detected by the submodule then it will send a STOP alarm that shuts down the boilers.

Set configuration parameter ALRM=0 in the Boiler Controller and ALRM=2 in the Changeover Submodule to enable this feature.

Using Changeover Submodule for Boiler Flue Dilution Fans

Primary PumpsPCO/DIN/3T/001

VT PumpsPCO/DIN/3T/002

Flue Dilution FansPCO/DIN/3T/001

Flue Dilution Fans


2 12 Heating Systems

Flue Dilution Fans`without Changeover submodule

The boiler output that drives the primary pump can be used todrive the Flue Dilution Fan. This can be driven directly from the Boiler module output if the pumps are controlled by a Changeover submodule or through a relay on the panel if not.

If the fan proving flow switch is required to be interlocked with the boilers - as it normally is - theneither wire to System Stop Alarm input on the Boiler Controlleror use relay logic interlocks but note that the fan status cannotbe observed from a PC interface.

Heating Systems Secondary Circuits 2 13

Secondary CircuitsFor simple systems with one Variable Temperature (VT) circuit,the Boiler Controller can control the VT Valve and Pump. For systems with multiple VT circuits or Constant Temperature (CT) circuits, Secondary Circuit Controllers are used. The Boiler Controller is still used to control one VT Circuit.

VT Circuit 1 feedingwet heating Zone 1

VT Circuit 2 feedingwet heating Zone 2

CT Circuit 3 feedingAHU Coils

Zone Controller 1

Boiler ControllerZone Controller 2

AHU Controller

Secondary CircuitController withPump Changeover

Secondary CircuitController withTemperature Controland Pump ChangeoverSubmodule

Secondary Circuits

2 14 Heating Systems Secondary Circuits

Two types of Secondary Circuit Controller are available for different applications•Temperature and Pump Control•Pump Control only

Temperature and Pump ControlThe Temperature of the water in the Secondary Circuit is controlled to a setpoint value lower than the Primary water using a mixing valve

Inputs A temperature sensor for the Secondary water Flow Temperature is normally fitted in this application.

Pumps The Controllers have an output to switch a single pumpTwin Pumpsets require an additional Changeover submodule Registered to the Secondary Circuit ControllerUse type PCO/DIN/3T/004

Which Type?There are three types of Secondary Circuit Controller with Temperature Control:•VTC Type Weather Compensation of the Secondary Water

Temperature. This is used with Radiator, Perimeter Heating and Under Floor heating applications. The Boiler’s inbuilt Secondary Circuit Control is always of this type.

•VTU Type Water Temperature varies depending on the demand level from its consumer units- Fan Coil’s, AHU’s. The Secondary Temperature is not Weather Compensated. This is the recomended control method for this type of plant.The energy efficiency is high as the temperature varies with demand rather than being at maximum design point at all times. This improves the plant efficiency and reduces pipework losses

•CTU Type Constant Temperature Control. Water at the constant Temperature setpoint is provided whenever the consumer units - Fan Coil’s, AHU’s etc have a Heat Demand.This type of control can be used where SeaChange Modules do not control peripheral plant. VFC input to module indicates demand and so brings module into Occupation

Note The Secondary Circuit Controller with Temperature Control is ordered with the appropriate Type preset for VTC, VTU & CTUThe Type can be changed from the Preset using the SPTY parameter. See Date sheet for details.


Weather Compensatedwith Adaptation

Weather Compensatedwithout Adaptation

Without WeatherCompensation

Radiators

Type VTC/DIN/3T/105

PerimeterHeating

Type VTC/DIN/3T/105

AHU’s andFan Coils

Type VTU/DIN/3T/105


Pump Control OnlyThe Temperature of the water in the Secondary Circuit is not independently controlled. The pump is used to pump water from the Boiler Primary Circuit when the consumer units - FanCoil’s and AHU’s have a Heat Demand and require Hot Water

Twin Pumpsets

•The Pump Changeover Version CTU/DIN/PCO/3T/XXX controls twin Pumpsets directly.

•must fit at least one VFC status signal to indicate pump is running n.b. it must be a status signal, trip signals will not work.Either a flow switch across each pump or a single one for the pump pair or auxiliary contact from pump motor starter one per pumpor one per pumpset

Single Pumps•The CTU/DIN/PCO/3T/xxx can also be used with single

pumps if the outputs are commoned. In this configuration the pump status can be monitored and alarmed but the WaterTemperature cannot be monitored

•The CTU/DIN/3T/105 can be used with its Optimum Start Switch Output switching the Pump. With this product the pump status is not monitored but the Flow Temperature can be. Alternatively this input can be configured to take a Volt Free Contact signal which forces the unit on. This is used with “legacy” systems that use other controls . The VFC is used to indicate the plant is running and that Hot Water is required


Twin Pumpset

Single Pump with StatusInput

Single Pump withTemperature or VFC Input

TypeCTU/DIN/PCO/3T/006

AHU’s and Fan Coils

AHU’s and Fan Coils TypeCTU/DIN/PCO/3T/006

AHU’s and Fan Coils TypeCTU/DIN/3T/105

Secondary Circuits

Zone 1

Zone 2

VT Circuit 2VTC/DIN/3T/105

CT Circuit 3 SecondaryCircuit Controller withpump changeoverCTU/DIN/PCO/3T/006

VT Circuit 2Pump ChangeoverPCO/DIN/3T/004

VT Circuit 1 is part of Boiler Controller

AHU driven from ZoneOccupancy Demand



Zone and CT Circuit Demand Signals•Secondary Circuits are Demand Driven

•each Weather Compensated heating circuit must have at leastone Zone Controller - it sends Energy Demand Signalsto the Secondary Circuit Controller or Boiler Controller for the first VT circuit in a system. The VT setpoint, and whether the pumps will run or not, is determined from this signal

•more than one Zone Controller can be used per secondary circuit; the highest Energy Demand signal will be used to determine the VT setpoint and pump status.

•CT Circuits must also have Energy Demand signals sent to them in order to make them run. Often, CT circuits feed multiple loads, e.g. AHUs, Fan Coils

•either each load must be controlled by a SeaChange Module e.g. AHU Controller, Fan Coil Controller

•or a Volt-free contact must be wired from the loads into the Secondary Circuit Controller otherwise the pumps will not run.



Sub ZonesEach Secondary Circuit of a wet heating system may be furtherSub-Zoned by introducing Zone Valves or Pumps. Each Sub-Zone will require its own Zone Controller. The Zone Controllers contain the control algorithm for temperature control, the sensors, Optimum Start, Fabric Protection and Occupancy Time functions.

The Zone Valve or Pump is controlled by an Actuator Submodule registered to the Zone Controller. Up to 8 Actuator Submodules may be registered to each Zone Controller. The Zone Controller generates a Control Demandsignal, which is sent to the registered Submodules over the network.

Zone Controllerfor Sub-Zone ‘A’

IntelligentActuatorSubmodules

VT Valve and Pump controlledby Boiler or Secondary CircuitController

ZoneControllerfor Sub-Zone ‘B’

Sub Zones

Using Zone Controllers and Actuator submodulesfor Sub Zone Control


Zone A Zone Valveup to 8 Actuatorsper zone

Actuators can be DIN mountedor Network Powered IntelligentActuators

Heat Demand toMain Boiler plant

Sub Zones

Heat DemandInterconnect

The Zone Valve / Pump may be switched in three different ways. Motor-open-spring-closed valves or Pumps are best controlled using Time Proportioning control; the valve/pump is switched on and off over a time period, usually a few minutes, with the on/off ratio determined by the Control Demand signal generated by the Zone Controller. Thus the heat input to the zone is controlled in a proportional manner

Raise/Lower type valves are controlled by Raise/Lower control using a pair of Triac outputs; the Control Demand signal will be directly translated into a valve position.

Zone BZone Valve

Secondary Circuit Controllercontrols VT valve and pump forWeather Compensated flow to bothsub-zonesVTC/DIN/3T/105

Zone Valves control Heat Input into sub- Zones


The unique SeaChange Intelligent Actuator works in this way;it is powered entirely by the network with a 2-wire connectionand mounts directly on the valve body.

Valves with 0-10V DC actuators require Analogue control; the Control Demand signal will be directly translated into a valve position.

Types of Control•temperature and time control, including Optimum Start, of

the space using a Zone Controller and Actuator Submodule with Time Proportioning output -use ACT/DIN/3T/101

•temperature and time control, including Optimum Start of the space using a Zone Controller and Actuator Submodule with Raise/Lower output - use ACT/DIN/3T/105 for driving conventional actuators, or ACD/VLV/LPR/... - this is an Intelligent Actuator which is the actuator itself with a built-in SeaChange Submodule; the Intelligent Actuator mounts onthe valve body, and is wired to the network. The network provides data communications and power to the module and Actuator Motor eliminating additional power supplies and wiring needed with conventional actuators.

• temperature and time control, including Optimum Start, of the space using a Zone Controller and Actuator Submodule with Analogue output - use ACT/DIN/AOP/721.

Sensors•Zone Controllers have integral sensors - fit extra wall-

mounting sensor if the Zone Controller is not mounted in thecontrolled space, or if control from both internal and externalsensor required - uses ZON/PTR/LCD/001.

•could use another version of the Zone Controller -ZON/PTR/LCD/003 -no integral sensor, facility for 2 remote mounted sensors

•could use Intelligent Sensor registered to the Zone Controllerif the wiring is more convenient; Intelligent Sensors are wired to the network, rather than directly to the Zone Controller, and may be installed anywhere on the network


Occupancy Times•are set on the Zone Controller

Fabric Protection•Zone Controller will control space to Non-Occupied Setpoint

during Non-Occupancy, to protect the building fabric against condensation damage

•use of Intelligent T+RH sensor allows RH-based Fabric Protection - use SEN/PTR/TRH/005. See Zone Controller description on CD for full details.

Zone Demands to Main Plant•the Zone Controller still needs to send its Energy Demand

signal for heating to the Boiler or Secondary Circuit Controller that is feeding this circuit so that the Sub-zones are fed with water at the required times. See Boiler and Secondary Circuit sections.

Heating Systems DHW Control 2 25

Boiler Controller

DHW Controller

Domestic Hot Water ControlDomestic Hot Water services can be LPHW heated from a central Boiler system, or Direct-Fired Gas systems or Electric heating, which have no linkage to the Wet Heating plant, but can share Occupancy Times with heating zones. Automatic changeover from LPHW to Electric heating of the DHW in summer can be achieved if desired - use type 110 OR 111 versions.

Domestic Hot Water

2 26 Heating Systems DHW Control

The DHW Occupancy Times can be set in a number of ways. The DHW times can be linked to one or a number of space heating zones or a dedicated Zone Controller can be used to set up independent Occupancy Times for the Domestic Hot Water Service. This Zone can also be used to remotely display the DHW temperature and adjust the DHW setpoint.

Types of Control• temperature and time control, including Optimum Start, of

the DHW via a control valve controlling LPHW flow to the calorifier coil - type DHW/DIN/3T/105

• temperature and time control, including Optimum Start of the DHW via a Time Proportioning output to enable the burner of a Direct Gas-Fired heater or switch the heating element of an Electric Immersion Heater - type DHW/DIN/3T/101

• time control only of a Direct Fired Gas or Electric heater withits own built-in temperature controls, using an Optimum Start Switch output for Optimum Start of the DHW service, you must fit a sensor for this to work, or Occupation Switchfor switching based on fixed Occupation Times with no Optimum Start - type DHW/DIN/3T/101 or types 108 or 109 for multistage heaters

• temperature and time control, including Optimum Start, of the DHW via a control valve controlling LPHW flow to the calorifier coil, but with automatic changeover to Electric Heating, based on Outside Temperature and whether the Boilers are running for any other purpose- type DHW/DIN/3T/111


Sensors•must fit DHW sensor if DHW temperature is to be controlled,

sensor should be fitted to storage calorifier, not to the secondary pipework as this may give a false reading when pumps are not running

•must fit DHW sensor if Optimum Start is to be used

•can fit DHW sensor for monitoring purposes if time control of a self contained DHW heater is used

Valves•valves are either Raise / Lower type, use DHW/DIN/3T/105

with Raise/Lower output driver

•or Motor-open-spring-closed type, use DHW/DIN/3T/101 with Time Proportioning output driver

• if 0-10V DC valves are used, you need an additional ActuatorSubmodule to give 0-10V DC outputs

Pumps•DHW secondary pump controlled from output on DHW

Controller

•Optimum Start Switch will run pump for warm-up and Occupation periods - good for large secondary circuits

•Occupation Switch will run pump for Occupation period only

•Primary Pumps. If the DHW circuit is fed from its own primary pumps these should be controlled by a secondary circuit controller, pump changeover type

Immersion Heater•single-stage Immersion Heater uses DHW/DIN/3T/101 with

Time Proportioning output driver

•multi-stage Immersion Heaters can use DHW/DIN/3T/108, 2-stage or /109, 3-stage Sequenced output drivers

•automatic changeover from LPHW to Immersion Heater, uses DHW/DIN/3T/110 for Motor-open-spring-closed valve or /111 for Raise / Lower valve

Occupancy Times•DHW Controllers must have their Time Schedules or

Occupancy Status set by one, or a number of, Zone Controllers. These Zone Controllers may be performing otherfunctions as well e.g. controlling space temperature

•either a single Zone Controller may be used to Time Schedule Supervise one or many DHW Controllers or Occupancy Demand signals may be sent from many Zone Controllers (or AHU or Secondary Circuit Controllers) to one DHW Controller

•SPTY parameter in DHW Controller determines whether Time Schedule Supervision or Occupancy Demand is used

•Optimum Start of the DHW service will only work if Time Schedule Supervision is used

•if Occupancy Demand is used, the DHW service will run whenever any of the zones registered to it is in Occupancy

•a dedicated Zone Controller may be used to set DHW times, adjust setpoint, and view temperature. If a Zone Controller is used in this way, it cannot be used for any other purpose.

2 28 Heating Systems DHW Control

Heat Demand toBoiler Plant

Master Zone sends Time Schedule to DHWController. DHW has its own Optimum Start.Zone can perform other system functions e.g. spacetemperature control etc

DHW Time Schedule Supervision



DHW runs when any of a numberof Zones is in Occupation.DHW does not Optimum Start

DHW Driven From Zone Occupation Demand

Zone Controller sets DHW setpoint fromadjustment knob. DHW runs when Zone inOccupancy and Optimum Start. Setremote PV on Zone to read DHWtemperature so that the Zone displaysDHW temperature


DHW temperatureas remote PVinput to Zone fromDHW controller

Zone Controller used to Set and DisplayDHW Temperature and Time Schedule

This Zone Controller cannot beused for space temperatureControl as well as DHW


Heating Systems Direct Heating 2 31

Direct Space HeatingDirect Space Heating may be controlled using Zone Controllerswith Actuator Submodules registered to them. The Zone Controllers contain the control algorithm for temperature control, the sensors, Optimum Start, Fabric Protection and Occupancy Time functions; the Actuator Submodule is connected to the heater. Up to 8 Actuator Submodules may be registered to each Zone Controller.

The heater may be switched in three different ways.

Gas-fired convectors are best controlled using Time Proportioning control; the heater is switched on and off over a time period, usually a few minutes, with the on/off ratio determined by the Control Demand signal generated by the Zone Controller.

Electric heaters may be controlled by the above method, or

Zone Controller

Solid-State Relay

Actuator Submodule with Fast TimeProportioning Output Driver type ACT/DIN/3T/421

Direct Space Heating

Electric HeaterBattery

Control of Electric Heating using Solid State Relay and Actuator submodule

more accurately by using Fast Time Proportioning control via an external Solid-State Relay (SSR). Fast Time Proportioning acts in the same way as Time Proportioning, but over a much shorter time period - a few seconds. This gives fully modulating control over the load.

The third technique is to use Analogue control via an external Thyristor Drive. This gives similar results to Fast Time Proportioning, but the components are usually more expensive.

Types of Control• temperature and time control including Optimum Start, of

the space using a Zone Controller and Actuator Submodule with Time Proportioning output - ACT/DIN/3T/101

• temperature and time control including Optimum Start, of the space using a Zone Controller and Actuator Submodule with Fast Time Proportioning output - ACT/DIN/3T/421. Must use an external Solid State Relay to switch the load

• temperature and time control including Optimum Start, of

2 32 Heating Systems Direct Heating

Direct Space Heating

Heat Demand does notdrive Boiler plantbecause heaters aredirect fired.Parameter HTSC = 0Default Value

Up to 8 Actuators canbe driven from eachZone controller

the space using a Zone Controller and Actuator Submodule with Analogue output - ACT/DIN/AOP/721. Must use an external Thyristor Drive to switch the load

Sensors•Zone Controllers have integral sensors - could fit extra wall-

mounting sensor if the Zone Controller is not mounted in thecontrolled space, use ZON/PTR/LCD/001

•could use another version of the Zone Controller - ZON/PTR/LCD/003 -no integral sensor, facility for 2 remote mounted sensors


Occupancy Times•are set on the Zone Controller

Heating Systems Direct Heating 2 33


Heating Systems Example 1 2 35

Examples2 Boilers, 1 Zone - Example 1

This example represents the smallest possible SeaChange System and comprises: •Zone Controller, every system must have one •Boiler Controller which contains the System Housekeeping

function•Power Supply - system will not function without one.

Boiler Controller

Zone Controller

Wet HeatingExample 1

Simple System with one Heating zone, one or two Boilers and Weather compensated VT Circuit

Boilers•are conventional Single-stage boilers.

•Boiler Controller is performing System Housekeepingfunction and therefore needs an Outside Temperature Sensor - could be a conventional sensor hardwired to its input terminals, or use an Intelligent Sensor connected to the network, and registered to the Boiler Controller

•Boilers will automatically sequence and duty-rotate on the basis of longest-on-first-off

• fixed sequencing is available if required - choose /003 variant

Sensors•must fit either primary flow or primary return sensor, best to

fit both

•must fit Outside Sensor - see above

•must fit VT flow sensor

•Zone Controller has integral sensor - could fit extra wall-mounting sensors if the Zone Controllers are not mounted in the controlled space, or if average/min/max control from 2 sensors is required

Pumps•Boiler Controller can switch the Primary and VT Secondary

Pumps

• for twin pumpset, use Changeover Submodules -see Example 2

• the Primary Pump will run when the boilers are running, and will run-on for an adjustable period - BRON Parameter

• the VT Secondary Pump will only run when the Zone is demanding heat; to make the pump run for the whole Occupancy Period, set parameter MIND = 0

VT Valve• the VT valve is Raise / Lower type; for 0-10V DC valves use

Analogue Output Secondary Circuit Controller to provide theVT Circuit Control

• the VT valve is used to control the VT temperature to a Weather Compensated setpoint, which is adapted up and down by Zone Demand to account for seasonal variations.

2 36 Heating Systems Example 1


• if you cannot provide a position for the Zone Controller or itsremote sensor, which adequately represents the whole zone’s temperature, e.g. a Hotel then you must: disable setpoint adaption, set TRNG and CRNG to zero, disable Zone Boost, set ZBST to zero. This stops Boilers controlling to MAXF during Optimum Startdisable demand-driven VT pump, set MIND to zero

• if you have an underfloor heating system, where flow temperature must be limited, set MXVT to the desired maximum

Zone Control•a Zone Controller is used to control the space temperature; it

provides temperature control, Optimum Start, Fabric Protection and a user interface for setting Occupancy Times and Setpoint.

•Zone Controller has integral temperature sensor - could fit remote wall-mounting sensor if the Zone Controller is not mounted in the controlled space, or if average/min/max control from internal and remote sensors (use sensor type - SEN/PTR/ROM/001) is required - use ZON/PTR/LCD/001

•could use another version of the Zone Controller -ZON/PTR/LCD/003 -no integral sensor, facility for 2 remote mounted sensors


Equipment List

1 BLR/DIN/STD/001 Boiler Controller with System Housekeeping1 ZON/PTR/LCD/001 Zone Controllers for temperature control of the

Area1 PSU/DIN/500S/230V/TER System Power Supply3 SEN/PR/IMM/001 Immersion Sensor - flow, return and VT

temperatures3 SEN/BP Pocket for Immersion Sensor1 SEN/PR/OAT/001 Outside Sensor

Clamp On sensors are also available

Interconnect Diagram•Heating Demand signal is generated by Zone Controller

Energy Consumer Module. This signal also containsOccupancy Status information

•The Zone Controller sends its Heat Demand signal directly to the Boiler Controller where it is used to control the VT Valve and Pump to give Weather and Demand-compensated flow temperature

•when the Zone is in its warm-up period during Optimum Start the Boiler Controller will Boost the VT Flow temperature up to its maximum value, set on MXVT. The Boiler Controller can determine when the Zone is in Occupancy, Non-Occupancy or Warm-up from the Demand Signal, so this is the only Interconnect that is necessary.

Wet HeatingExample 1


Boiler plant is enabled by Heat Demand Interconnectfrom Zone Controller


Configuration Parameter SettingsAutomatically set during Registration

•HTSC Parameter in the Zone Controller will be automaticallymodified during the registration process. It is set to 1 to “point” the Heating Demand at the Boiler Controller, where itwill be interpreted as a demand for the VT Circuit

Parameters that must be set manually•no parameters have to be manually adjusted for most

common applications.

Examples of Parameters that may need to be set manually•the Boiler Controller normally controls 2 boilers. If only one

boiler present, set parameter BLRS = 1.

• if lockout alarms are wired to the Boiler Controller, the ALRM and ALST Parameters may need to be adjusted - see Data Sheet

• if no Zone Demand adaption of the Compensated flow temperature is required because the Zone Controller is not reporting a demand signal that is representative of the wholespace e.g. Perimeter Heating application, or Hotel heating where individual rooms cannot be sensed then set parameters CRNG and TRNG = 0 to disable zone influence.

•setting ZBST=0 will disable the automatic boost that would occur during Optimum Start. Normally the VT Setpoint will be boosted from its nominal Weather and Zone Compensated value to a maximum setting (MXVT) until the Zone Controller is within 1 degC of setpoint.

• setting MIND=0 will keep the VT and Primary Pumps running continuously during Occupancy. With MIND non-

zero, the pumps will turn off if there is no Zone Demand. This may benecessary if sensors cannot represent the whole space requirement.

•Summer Cut off parameter SMRT is used to inhibit heating from running during summer, providing an automatic Summer/Winter switch. For some applications this may need to be adjusted from its default value of 18 degC outside temperature.


• VLIM parameter is used to enable back-end protectionThis protects boilers from corrosion damage due to condensation of flue gas combustion products- see Data Sheet for full details.

VLIM=100 (Default) disables this feature as it gives no limitation on Valve Position

If VLIM set to say 50 then VT Valve opening is limited to 50% until Return Temperature exceeds Minimum Return Temperature Parameter MINR Default 40 Deg C

If a Shunt/Primary Pump is being used, it is advantageous to enable this feature by setting VLIM=0

Multi Boilers, Multi Zones - Example 2Boilers

•Boilers are conventional Single-stage units.

•Boiler Controller is performing System Housekeeping function and therefore needs an Outside Temperature Sensor- could be a conventional sensor hardwired to its input terminals, or use an Intelligent Sensor connected to the network, and registered to the Boiler Controller

•fixed sequencing is available if required - choose /003 variant• first 2 stages are switched by the Boiler Controller; stages 3

and 4 are switched by a Cascade Submodule registered to the Boiler Controller


area A

area B

area C

Wet Heating Example 2

Multi Zone, Multi Boiler Heating Example


fit both


•must fit VT flow sensors to both secondary circuits

•must fit DHW temperature sensor to DHW Calorifier

•Zone Controllers have integral sensors - could fit extra wall-mounting sensors if the Zone Controllers are not mounted in the controlled space, or if average/min/max control from 2 sensors is required

Pumps•Twin Primary Pumpset controlled from Changeover

Submodule - if a single Primary Pump, can control directly from Boiler Controller

•Areas ‘A’ and ‘B’ have a single VT pump; this is controlled by the Boiler Controller. If a Twin Pumpset fitted, use PCO/DIN/3T/002 registered to Boiler Controller

•Area ‘C’ has a Twin Pumpset; this is controlled by a Changeover Submodule registered to the Secondary Circuit Controller. A single pump could be controlled directly by theSecondary Circuit Controller. Status signals will be needed for the pumpset. Use PCO/DIN/3T/004

• the DHW Secondary Pump is controlled by the DHW Controller, as an Optimum Start Switch output, so that it runs for the Optimum Start and Occupation periods irrespective of demand

Valves•valves are Raise / Lower type; if 0-10V DC valves are used,

fit Analogue Secondary Circuit Controller to give 0-10V DC outputs

• the VT valve for Areas ‘A’ and ‘B’ is controlled by the Boiler Controller

• the Sub Zone valves for Area ‘A’ and ‘B’ are controlled by Intelligent Actuators which control the valve directly, and are powered from the network and registered to the Zone Controller for their Area.

• the VT valve for Area ‘C’ is controlled by the Secondary Circuit Controller

• the valve for the DHW primary is controlled by the DHW Controller


Zone Control•a separate Zone Controller must be used for each Area. They

provide temperature control, Optimum Start, Fabric Protection and a user interface for setting Occupancy Times and Setpoint.

•3 Master Zones are used. This provides independent time schedules for each zone. Alternatively use one Master Zone and two Slave Zones (ZSL/PTR/LCD/001) if the time schedulefor each area is to be the same. Time schedule for all areas is then set on the Master Zone.

•one of the Zone Controllers is also being used to provide Time Schedule Supervision of the DHW Controller; this means that the DHW will be available at the same time that Area ‘A’ is occupied, and the DHW will Optimum-Start to get to setpoint for the start of occupancy

•an alternative is to drive DHW based on Occupancy Demandfrom all Zones; this means that the DHW is enabled when any of the Zones is in Occupancy. However, the DHW cannotnow use Optimum Start, but will run if any Zone is Overridden out of normal Occupancy Times

Equipment List1 BLR/DIN/STD/001 Boiler Controller with System Housekeeping for

2 boilers and VT Valve/pump for areas A and B1 CAS/DIN/3T/001 Cascade Submodule for additional 2 stages1 PCO/DIN/3T/001 Changeover Submodule for Primary Pumps1 VTC/DIN/3T/105 Secondary Circuit Controller with Temperature

control, Weather Compensated for area C1 PCO/DIN/3T/004 Changeover Submodule for Area C VT pumps

(registered to Secondary Circuit Controller)3 ZON/PTR/LCD/001 Zone Controllers for temperature control of

each Area2 ACD/VLV/LPR/002 Intelligent Actuators for Zone valves A and B1 PSU/DIN/500S/230V/TER System Power Supply1 DHW/DIN/3T/105 DHW Controller with outputs for Raise/Lower

valve and Secondary Pump5 SEN/PR/IMM/001 Immersion Sensor for primary Flow and Return,

2 VT secondary temperature, 1 DHW5 SEN/BP Pocket for Immersion Sensor1 SEN/PR/OAT/001 Outside Air Temperature Sensor

Clamp On Temerature Sensors also available


Zone ‘A’Control

Zone ‘B’Control

Zone ‘C’Control

Zone ‘A’Zone valve

Zone ‘B’Zone valve

DHW Calorifier

Boiler stages 1 and 2and Zone ‘A’ and ‘B’VT valve and pump

Zone ‘C’VT valveControl

PrimaryPumpset

Boiler stages3 and 4

Zone ‘C’Pumpset Control

Wet Heating - Example 2Interconnect Diagram


Interconnect Diagram•Heating Demand signals are generated by Zone Controllers

and DHW Controllers -Energy Consumer Modules. These signals also contain Occupancy Status information

•Areas ‘A’ and ‘B’ send their Heating Demand signal directly tothe Boiler Controller where the highest is used to control the VT Valve and Pump to give Weather and Demand-compensated flow temperature

•Area ‘C’ sends its Demand signal to the Secondary Circuit Controller where it is used to control the VT Valve to give Weather and Demand-compensated flow temperature.

•Areas ‘A’ and ‘B’ could each have multiple Zone Controllers; the VT flow temperature would be based on the Controller which was sending the highest Demand signal.See also Sub-Zones

•The Secondary Circuit Controller sends a Heat Demand signal as a Temperature Setpoint to the Boiler Controller where it is used to set the Primary Flow temperature.

• the DHW Controller sends a CT Demand signal to the Boiler Controller where it is used to set the Primary Flow temperature.

•each Zone Controller sends Control Demand signals to its Intelligent Actuator to position the Zone Valve


•HTSC Parameters in the modules will be automatically modified during the registration process. Notice that the HTSC parameter in Zone ’C’s Zone Controller has been set to 2, to “point” its Heating Demand at the Secondary Circuit Controller, which has address H2. All other modules with a Heating Demand output interconnect are pointing at H1, the Boiler Controller.

•BLRS Parameter in the Boiler Controller will automatically be updated to 4 (default value is 2) when the Cascade Submodule is registered to it.


Parameters that must be set manually

•no other parameters have to be set Manually

Examples of Parameters that may need to be set manually

•if an odd number of Boiler Stages - 1,3,5 etc. was present, theparameter BLRS would need to be adjusted accordingly.

• if lockout or other alarms are wired to the Boiler Controller and Cascade Submodules, the ALRM and ALST Parameters may need to be adjusted - see Data Sheet

• if no Zone Demand adaption of the Compensated flow temperature is required because the Zone Controller is not reporting a demand signal that is representative of the whole space e.g. Perimeter Heating application, or Hotel heating where individual rooms cannot be sensed, then set parameters CRNG and TRNG = 0 to disable room influence.

•setting ZBST to zero will disable the automatic boost that will occur during Optimum Start. Normally the VT Setpoint will be boosted from its nominal Weather and Zone Compensated value to a maximum setting (MXVT) until the Zone Controller is within 1 degC of setpoint .

•setting MIND to zero in the Boiler Controller will keep the Primary and VT pumps running continuously during Occupancy.With MIND non-zero, the pump will turn off if there is no Zone Demand. This may be necessary if sensors are poorly located and cannot represent the whole space requirement.

• Summer Cutoff parameter SMRT is used to inhibit heating from running during summer - an automatic Summer/Winter switch. For some applications this may need to be adjusted from its default value of 18 degC outside temperature.

• VLIM parameter is used to enable a back-end protectionfeature. This protects boilers from corrosion damage due to condensation of flue gas combustion products- see Data Sheet for full details. If a Shunt/Primary Pump is present, it is advantageous to enable this feature by setting VLIM to zero


Multi Boilers, Multi CT Circuits - Example 3This example works in conjunction with examples in other sections to describe a complete application for a large Commercial Building. This part of the example describes the Boiler Plant

•Boilers are 2-stage (Hi/Lo fired)

•Boiler Controller is performing System Housekeepingfunction and therefore needs an Outside Temperature Sensor - could be a conventional sensor hardwired to its input terminals, or use an Intelligent Sensor connected to the network, and registered to the Boiler Controller

• fixed sequencing is available if required - choose /003 variant

CT CircuitfeedingAHUs

CT CircuitfeedingFan Coils

Boiler Controller

SecondaryCircuitControllerwith PumpChangeover

SecondaryCircuitControllerwith PumpChangeover

Cascade Submodules

Changeover Submodule

Wet Heating - Example 3


Multiple Hi-Lo Fired Boilers Feeding AHU’s and Fan Coils viaConstant Temperature Circuits

•first 2 stages are switched by the Boiler Controller; stages 3 through 8 are switched by Cascade Submodules registered tothe Boiler Controller. Note that the Boiler Controller will keep the 2 stages of each Boiler together in the sequence to prevent Hi fire being enabled before Lo fire

Large Systems•for systems with large numbers of Fan Coils, normally above

100, check that the Registration Capacity of the Boiler Controller is not exceeded - you may need to use a Floor Controller as the Housekeeper instead, in which case you will need to choose a non-housekeeping Boiler Controller. See System Design Section for details


fit both


Primary Pumps•Twin Primary Pumpset controlled from Changeover

Submodule - if a single Primary Pump, can control directly from Boiler Controller

Secondary Pumps•both CT Circuits have a Twin Pumpset; these are controlled

by Secondary Circuit Controllers with Pump Changeover CTU/DIN/PCO/3T/....

• if you want the pumps to run when Fan Coils or AHUs are running, choose type /004. If you want the pumps to run only when the Fan Coils or AHUs are both running and demanding heat, choose type /006. Remember that if you choose a type /004 the Pumpset and Boilers will run for the Optimum Start and Occupancy Period irrespective of the season.Type /005 runs for the Occupancy Period but not Optimum Start

Energy Demands•both of the secondary circuits are Demand Driven; they must

have Heating Demand Signals fed to them from other SeaChange Modules, otherwise the pumpset will not run, which in turn will mean that the Boilers and Primary Pumps will not run. See AHU and Fan Coil section for further detailsof this example


•every Heating load on each circuit must be represented by a SeaChange Module. If this is not possible i.e. if the Fan Coils were not controlled by SeaChange, then an alternative approach must be adopted.

Legacy Systems•A Volt-free Contact from the terminal unit plant can be used

to drive the CT circuit. The CT Circuits are controlled by Secondary Circuit Controllers with Temperature Control CTU/DIN/3T/101 although the temperature control feature would not be used with Changeover Submodules PCO/DIN/3T/004 registered to them. The CTU with temperature control has an input to which a Volt-Free Contact may be wired to force CT Controller into Occupancy - see Secondary Circuit section


Equipment List

1 BLR/DIN/HIL/001 Boiler Controller for Hi/Lo Boilers with System Housekeeping*

3 CAS/DIN/3T/001 Cascade Submodule for additional 6 stages1 PCO/DIN/3T/001 Changeover Submodule for Primary Pumps2 CTU/DIN/3T/PCO/006 Secondary Circuit Controller with Pump

Changeover function -see above for optionsAir Handling Units See AHU Section Fan Coils See Terminal Unit Section

1 PSU/DIN/500S/230V/TER System Power Supply - note; number and type of PSUs needs to be considered for the system as a whole - see System Design Section

2 SEN/PR/IMM/001 Immersion Sensor - primary flow and return temperature

2 SEN/BP Pocket for Immersion Sensor1 SEN/PR/OAT/001 Outside Air Temperature Sensor

Clamp On sensors also available

* If this is a large Fan Coil system >100 Zones then Housekeeping will be in a Floor Controller. See Fan Coil Section 4

Interconnect Diagram•Heating Demand signals are generated by AHU Controllers

and FCU Controllers - Energy Consumer Modules - not shown here, see AHU and Fan Coil sections. These signals also contain Occupancy Status information.

•The Secondary Circuit Controllers collate the Heating Demands from the AHU and Fan Coil Controllers and send a CT Demand signal to the Boiler Controller where it is used toset the Primary Flow temperature.

Primary Pumpset

Boiler stages 3 & 4

Boiler stages 5 & 6

Boiler stages 7 & 8

Boiler stages 1 & 2

Heat Demandsignals from FanCoil controllers -see Fan Coilsection

Heat Demandsignals from AHUcontrollers - seeAHU section

Wet Heating - Example 3Interconnect Diagram



•HTSC Parameters in the Secondary Circuit Controllers will be automatically set to 1, to “point” the Heating Demand signal at the Boiler Controller, which has address H1. The HTSC parameters in the AHU Controllers will be set to 3, and the HTSC Parameters in the Fan Coil Controllers will be set to 2 to “point” to the relevant Secondary Circuit Controllers H3and H2 respectively.

•BLRS Parameter in the Boiler Controller will automatically be updated to 8 - default value is 2, when the Cascade Submodules are registered to it.

Parameters that must be set manually

•no other parameters have to be adjusted

Examples of Parameters that may need to be set manually

•if lockout or other alarms are wired to the Boiler Controller and Cascade Submodules, the ALRM and ALST Parameters may need to be adjusted - see Data Sheet

• the Secondary Circuit Controllers have a “grace time” associated with the Changeover function to allow time for flow switches to make contact after pumps have started. Thiscan be adjusted on parameter DLAY


Documents

Heating Systems - vusite.net · 2 Heating Systems Boiler Controls 2 3 ... back-end protection ... or use relay logic interlocks but note that the fan status cannot