Feature Notes
Boiler Controller for Medium Temperature Hot Water Control (MTHW)
BLR / DIN / MTHW /.../ ...
Main Features Ideal for MTHW heating applications Controls 2 MTHW Boilers and associated plant Up to 8 Boilers in one sequence using Boiler Cascade Submodules Self adapting Weather Compensation System Housekeeping function Boiler plant operates on demand from the building, not fixed time programme

This product is available to special order only : please contact smartkontrols for availability

Summary Features

General

The Boiler Controller is an Energy Provider Module in the SeaChange system; that means that it provides heat energy to Distributor Modules (perhaps controlling secondary circuits) or Consumer Modules (which are responsible for using the energy). It will only function when it receives Demand signals from these other modules; in this way, the plant will only run when it is needed, rather than on a timed basis as is common in conventional control schemes.

Configuration parameters can be set to allow operation to match the plant control requirements. A full table of configuration and monitoring parameters is detailed later in this data sheet.

A table of available product versions is shown on the last page.

This boiler variant supports MTHW boilers, the core functionality is the same as all other SeaChange boiler modules but is available only as boiler plus variable temperature circuit. The main changes are for reasons of safety due to the aggressive nature of the medium.

Primary Circuit Temperature Control

Unlike other 'standard' SeaChange Boiler Controllers which reduce the primary setpoint according to the prevailing demands (see BLR/STD & BLR/HIL for details), the BLR/HT will, under normal operation, always control the flow setpoint FLSP to 5°C less than the maximum flow temperature MAXF as long as there is demand albeit regardless of the level of demand. This is to ensure that the MTHW temperature is always maintained during demand situations. The flow setpoint will only be raised up to MAXF under 'zone boost' conditions.

VT Circuit Temperature Control

Operation of the Variable temperature circuit is as per other 'standard' SeaChange Boiler Controllers, except under VT sensor failure, when the VT valve will be held 'shut'.

As with other Boiler Controllers, the VT circuit will control to the Heating setpoint while any Zone Controller is demanding heat; when all Zones are satisfied, the setpoint will reduce to the FRST Frost Protection setpoint parameter and the pumps will turn off (unless the MIND Minimum Demand parameter is set to zero - see Pump Control and Demand later in this document). Thus the local VT Circuit controlled by the Boiler Controller will be run only when necessary, and then to the lowest possible temperature to satisfy all of the zones.

Description of Features

Occupation Control

The Boiler Controller does not have any time settings of its own, as it is entirely Demand Driven from heating demand signals generated by other controllers. The parameter MIND can be used to set a minimum level of demand that will bring the boilers on. At least one Zone Controller is required in the system to set Occupation Times for the building.

Boiler plant is enabled by Heat Demand interconnect from Zone Controller.

Flow & Return Temperature Control

The Boiler Controller is capable of several different methods of controlling Flow and Return Temperatures. The Controller decides which method to use depending on which sensors are connected to it.

On the BLR/HT, temperature sensors must now be fitted in pairs. Two in the flow and/or two in the return (Note these should be mounted in close proximity to each other). This is done to improve measurement accuracy and for safety. In either case, flow or return, one of the sensors is a Low Temperature sensor (type 10K3A1 - consult the manufacturers for order code) connected to the flow or return of the boiler module; the second sensor is a High Temperature sensor (type 100K6A1 - consult the manufacturers for order code) connected to Input 'a' or 'b' (flow or return respectively) of the module.

Best control is achieved using Flow Temperature sensors if only one point of reference is used. The parameter SACT may be used to force the Boiler Controller to use flow, return or an average of both temperatures. The default setting SACT = 1 will control using the flow sensors only.

Parameter MAXF is used to set the Maximum Primary Temperature control setpoint selected by SACT. MINR is used to set the Minimum Return Temperature control setpoint, which is important for protecting some boilers against back-end corrosion. In order to maintain the Minimum Return Temperature during morning start-up, the VT Valve will limit its opening to mix the cold return water from the VT circuit with the hotter primary water; this effect can be limited, or disabled altogether, using the VLIM parameter, see Boiler Back-End Protection section.

The sensor pairs are constantly checked and the boiler module will take action on either sensor failing. Checks are made for open or short circuit and in operation the sensors must measure within 10°C of each other.

Boiler Primary Setpoint Calculation

Unlike other Boiler Controllers which reduce the primary setpoint according to the prevailing demands (see BLR/STD & BLR/HIL for details), the BLR/HT will, under normal operation, always control the flow setpoint FLSP to 5°C less than the maximum flow temperature MAXF as long as there is demand albeit regardless of the level of demand. This is to ensure that the MTHW temperature is always maintained during demand situations. The flow setpoint will only be raised up to MAXF under 'zone boost' conditions.

Weather Compensation and Trim

The Boiler Controller runs the Boiler Plant on the basis of demand signals that it receives from other SeaChange Controllers. For the heating circuit, the demand is received from one or more Zone Controllers, which provide Optimum Stop/Start control of the occupied space.

The Boiler Controller controls water temperature for the VT circuit according to a Weather Compensated setpoint; this is further modified by demand signals from the Zone Controllers to produce the Heating setpoint. Any Zone or Slave Zone Controllers which are registered to the Boiler Controller for the purposes of Heating Demand (i.e. their HTSC parameter is set to point to the Boiler Controller) and whose parameter HTCT is set to 0 will be used in the calculation.

Weather Compensation with Zone Trim and Adaption

Zone Controllers produce demand signals varying between -100% (full cooling) and +100% (full heating). The Boiler Controller adapts the Weather Compensation to “learn” the building’s characteristic by keeping the highest-demanding Zone device at a +50% demand level during occupancy.

If the demand level is above or below 50%, the Weather Compensated setpoint is modified by two effects in the Fuzzy Logic Control loop; the trim effect will rapidly raise or lower the setpoint to take care of short-term changes in load.

The adaptive effect will additionally raise or lower the setpoint if the “error” from the 50% level is sustained over a long period, which represents the control system “learning” the thermal characteristic of the building.

The effects of these adaptations can be limited; the maximum excursion from the Weather Compensated setpoint caused by these effects can be set on two Configuration Parameters: TRNG sets the maximum trim effect, and CRNG sets the maximum influence of the adaptive effect.

These setpoint calculations remain active when the Controller is in an Occupied state (see Occupation Control, earlier in this document). At all other times, it will control to its non-occupied setpoint, FRST.

It is possible to disable Zone Trim and Adaption completely by setting CRNG and TRNG to 0. See Weather Compensation without Zone Trim and Adaption section.

Other Features

MXVT is a limit to VT flow temperature, (useful for limiting the flow temperature in underfloor heating applications), and also defines the Weather Compensated setpoint at 0 Deg C Outside temperature.

FLAV defines the unadapted Weather Compensated setpoint at 10 Deg C outside temperature.

SMRT defines a summer cut off temperature; when the outside temperature exceeds this value, the VT heating circuit will be inhibited (the primary circuit will be allowed to run for CT demands only).

Boost Mode

When any of the participating Zones are more than 1.0 DegC below their setpoint, they will drive the Heating setpoint into a Boost condition; it will temporarily leave the Compensation Curve with its adaption, and be set to the maximum permissable temperature, MXVT. Only when all Zones are within 1.0 Deg C of their respective setpoints will the Heating setpoint return to the adapted Compensation curve. This is done in order to perform the fastest possible Optimum Start, and also to provide a predictable heat input to the Zone in order that the Zone Controller’s Optimum Start self-adaption will work properly.

In addition, on the BLR/HT the flow setpoint FLSP will be raised up to MAXF under 'zone boost' conditions.

Disabling Boost Mode may be necessary if none of the participating Zones are reading a representative temperature (for instance, a Hotel heating system where it is impractical to put sensing in all of the rooms, and a simple Weather Compensated scheme will suffice). In this case, ZBST may be adjusted to disable Boost. Be aware that doing this will almost certainly disrupt the Optimum Start abilities of the system. See also Weather Compensation without Zone Trim and Adaption.

Weather Compensation without Zone Trim and Adaption

In certain applications (for instance, a Hotel heating system where it is impractical to put sensing in all of the rooms) the Zone Controller(s) may not be located in positions which give adequate sensing of the whole controlled space. If the Boiler Controller was left with its default parameter settings, this would result in the boiler adapting its VT setpoint according to an inappropriate Zone Demand (see Zone Trim and Adaption), the Boiler Controller may stay in Boost Mode for longer than is necessary, and also the VT pump would stop when the Zone(s) were satisfied (see Pump Control and Demand).

In these circumstances, the Boiler Controller should be set to simplify the Weather Compensation by ignoring Zone Demands:

If these settings are made, the Zone Controller(s) still control the Optimum Start of the space, as well as Fabric Protection. Be aware, however, that during mid-season (i.e. when heating may not be required, but Outside Temperature has not risen above the SMRT setting) the VT pump will continue to run all day. To stop this happening, Occupancy Times in the Zone Controllers must be set to no occupation.

Boiler Sequencing and Duty Rotation

Multiple Boilers will be automatically rotated in their sequence on the basis of “longest running boiler goes off first”. This shares the plant duty between the boiler stages, and also gives good controllability under part load conditions. The sequence is reset if the boilers have all been off for more than 9 hours.

A Fixed sequence version of the Boiler Controller is available if required (see back page for order code). This is useful where modular boilers must be brought on in a fixed sequence, such as when single and two stage boilers are mixed; or where a condensing boiler should always be first in the sequence.

The Boiler Controller can directly control 2 individual boilers or boiler stages. Additional stages can be added up to a maximum of 8 stages, by using Cascade Submodules. Use parameter BLRS to set the number of boilers to be controlled.

Particularly useful on the BLR/HT is the 'All Remote' feature which allows all the boilers to be sequenced by Cascade Submodules, allowing the Boiler Controller status inputs to be used for the additional High Temperature flow and return sensors (mandatory on BLR/HT), with each submodule monitoring the boilers.

To use the All Remote feature, set AREM = 1 in the Boiler Controller. In this mode, boiler outputs on the Boiler Controller are disabled, and only the outputs on the Cascade Submodules are enabled. The inputs on the Cascade Submodules are used for Boiler Status/Lockout and the Boiler Controller inputs for the additional High Temperature flow and return sensors.

Modulating Boilers

Control of modulating boilers or combinations of modulating and normal boilers can be achieved using analogue output Actuator Submodules. Each submodule type ACT / DIN / 3T / 721 can control one modulating boiler. The submodule takes the slot of one Cascade Submodule and hence a maximum of four modulating boilers can be controlled.

Control is provided in a fixed sequence only. The Actuator Submodule Output A modulates the boiler and output B switches the boiler on/off via a relay module (i.e. SeaChange RLY/DIN/10V/6A). Outputs on either the Boiler Controller or Cascade Submodules should not be used to switch on/off the modulating boilers.

Each Actuator Submodule should be set up to control over the Control Demand range using parameters HRMN and HRMX. For example a 2 boiler system would have the first actuator submodule set as HRMN = 0 and HRMX = 50, the second submodule would be set as HRMN = 51 and HRMX = 100. With these settings the first boiler will modulate over the first 50% of the Boiler Controller’s BLOP output and the second will modulate over the second 50% of the BLOP output. The MIND parameter on each submodule should not be set to less than 2.

Example: - Control of 2 Boiler modulating burners using Actuator Submodule 1 for 0 -50% and Actuator Submodule 2 for 51 - 100%.
Note maximum limit of Submodules applies

Example: - Control of 3 Boilers with modulating first stage using Actuator Submodule for 0 - 30% and Cascade Submodule for boiler 2 and 3. BLRS is set to 3.
Note maximum Submodule limit applies.

Register Cascade Submodules before Actuator Submodules.

Pump Control and Demand

To maximise energy efficiency, normally the VT Pump will run only when a heating demand exists; when the Zones are satisfied, the Pump will stop and the boilers will control to the frost setting FRST instead of the weather compensated value. If, however, the Zone Controllers are not optimally located to give a comprehensive indication of demand from all areas, the MIND parameter can be set to zero. This will mean that the boilers and pumps will run, controlling to the heating setpoint (set by Weather Compensation with Zone Trim and Adaption), for the whole of the Occupation period. Alternatively, parameters in the Zone Controllers may be set to achieve a similar result while minimising the overheating effect that may otherwise occur (see Zone Controller Data Sheet for further details).

The Primary Pump is started as the first Boiler is fired and continues to run-on after the Boiler(s) have shut down. The BRON parameter sets the run-on time for the Primary Pump. If desired, the VT pump and Valve may be made to run-on for the same time by setting MODE parameter. (Note this feature is only available in Boiler Controllers with Housekeeping; the MODE parameter in non-Housekeeping Boiler Controllers is fixed MODE=0).

Actuator Controllers registered to Zone Controllers will normally shut their valves during a boiler run on period, as boilers are not receiving Heat Demand in this condition. When MODE = 2 these Zone valves are rescaled or overridden. During normal operation the valve with highest demand is rescaled to 100% open , and others are opened proportionally (e.g. if highest demand is 60% and next highest is 30% then actuators will be driven respectively 100% and 50%.). During the run on period, these valves are all overridden to 100% unless they are cooling.

Twin Pump Sets

If either of the primary or secondary circuits have twin pumps sets, then they can be controlled by using Pump Changeover Submodules.

Note maximum limit of Submodules applies.

The Boiler Controller can be interlocked with Pump Changeover Submodules such that failure of BOTH pumps causes the Boiler Controller to shut down its outputs. The Boiler Controller must be set to ALRM>0 and the PCO Submodule must be set to TYPE=1 or 2, ALRM=2, ACLR=1. Upon a dual pump failure the PCO Submodule goes into alarm and signals the Boiler Controller and its submodules to shut down. As the Boiler Controller shuts down it generates a PMPF Pump Failure Alarm. Meanwhile the originating PCO Submodule is also shut down and its alarms are cleared. The PMPF condition however remains latched in the Boiler Controller and neither it nor its submodules can be operated until the condition is cleared. Once the fault has been rectified the PMPF alarm can be cleared and the Boiler Controller and all its submodules can be returned to normal operation by pressing the override button on the Boiler Controller or setting ALRM=0.

DHW Priority

The DHWP parameter may be set to give priority to DHW where the plant is sized for Heating or DHW, but not both, or where a fast DHW recovery is required; if this is used, the VT circuit will be disabled until all DHW services are up to temperature. Note that if DHWP is set but CT demands come from other controllers (e.g. AHUs) then the VT valve shuts whenever a CT demand exists.

Maintenance mode

In Maintenance mode, the Boiler Controller simulates a 50% demand signal from Zone Controllers, so the heating will control to the Weather Compensated setpoint. This is useful for commissioning during the summer months, when no heating demand exists.

The Controller is put into Maintenance Mode by holding down the Override button until the status light flashes rapidly; the Controller will stay in this mode until the button is pressed again.

Submodules

The Boiler controller can have up to 4 Cascade or Actuator Submodules and 3 Pump Changeover Submodules registered to it (type / 001 for primary pumps or flue dilution fans, or type / 002 for VT pumps). The submodule limits are reduced to 2 Cascade or Actuator Submodules and 1 Pump Changeover submodule for the / NH / non-housekeeping versions of the Boiler controller.

Frost Protection

Frost Protection is arranged as a 3-Stage sequence, which operates from a Frost Protection setpoint relating to Outside Air Temperature.

Operation of the BLR/HT under frost conditions is identical to 'standard' SeaChange Boiler Controllers, except under Low Temperature sensor fault, when only stage 1 will be available.

Stage 1 is invoked if the Outside Temperature falls below the Frost Protection setpoint FRST. The Primary and VT Pumps will run for the first 10 mins in every hour, with the VT circuit closed to the Boilers.

Stage 2 is invoked as the temperature in any of the water circuits falls to 5 DegC. The Primary and VT Pumps now run continuously. Stage 2 will only be seen if FRST is set below 5 Deg C.

Stage 3 is invoked if the temperature in any of the water circuits reaches the Frost Protection setpoint FRST. The Pumps will run, Boilers will now fire and the VT circuit will open until all water temperatures reach 30 DegC.

Disabling Frost Protection

Stages 1 and 2 Frost protection may be disabled; this may be useful in a Domestic installation, where the noise of pumps running during the night is intrusive, and pipework is all contained in occupied parts of the building, and is hence unlikely to freeze. The procedure is deliberately made complex, in order to avoid inadvertant use:

Access the FRST parameter using a Zone Controller (see our ‘Design Guide’ publication for details), and reduce it to its lowest allowable setting of 2°C. Now put the Boiler Controller into Maintenance Mode (see former section) and temporarily “short” the Outside Sensor connection using a wire shorting link. Refresh the FRST variable (by pressing Select on the Zone Controller); it will now display as 0°C, this value can now be “written” (i.e. pressing the Override button on the Zone Controller) to the Boiler Controller.

Take the Boiler Controller out of Maintenance Mode and remove the shorting link, confirm the FRST setting is 0°C, the variable is now fixed at 0°C and cannot be adjusted by normal methods. When frost protection is disabled, boilers will be brought on if the water temperature falls below 5 Deg C.

To re-enable frost protection, select the FRST parameter and put the Boiler Controller into Maintenance Mode. Press the Override button on the Zone Controller (to “write” the parameter to the Boiler Controller); the FRST parameter will default back to 3°C. Take the Boiler Controller out of Maintenance Mode, the 'FRST' variable can now be set as normal to any permissible value.

Fabric Protection

Fabric Protection is an independent process operating in Zone and Slave Zone Controllers, to protect the building fabric against damage due to condensation. If the temperature in the space falls below the Non-Occupied setpoint (usually set to 10 DegC) the Zone Controller will send a demand signal to the Boiler Controller, which will start the plant in the usual manner (see Zone Controller Data Sheet Z1).

Boiler Back-End Protection

It is important that water returning to the boilers is kept above a minimum temperature (unless the boiler is a Condensing Boiler). This is in order to prevent the boiler flue gases from condensing; if this happens, the resulting condensate mixes with the products of combustion, forming a corrosive liquid which will attack the boiler.
The parameter MINR may be set to control the Minimum Return Temperature. In steady state conditions, if the Return Temperature falls close to MINR, the Flow setpoint will be raised (thus overriding the setpoint generated by demand signals from other modules).

During start-up, the Return Temperature may be low, and elevating the Flow setpoint may not be sufficient to bring the Return Temperature to an acceptable value. If the hydraulics of the system will allow, the VT Valve may be overridden to the closed position (to the Secondary Circuit) thus allowing the primary water to return directly to the boilers, and hence meet the requirements of MINR. As the required Return Temperature is met, the VT Valve will be allowed to open gradually until steady state conditions are reached. The VT valve will be held at the VLIM setting when the return is 10 Deg C below MINR.

The amount by which the VT Valve is allowed to close can be limited by parameter VLIM. If VLIM is set to 100, the Back End Protection Override of the VT Valve is disabled. A setting of 50 will allow the valve to close to 50%, and a setting of 0 will allow the valve to close completely.

Alarms

The Boiler Controller may be set to generate Alarms, which may be sent to a SeaChange Doorway Supervisor (either locally connected to the system, or via an autodialling modem). Alarms may be enabled by setting the ALRM parameter.

Alarm codes as they appear at Doorway Supervisor and InSite tool:

Danger of Freezing

This Alarm is generated when any of the connected water temperature sensors (Flow, Return or VT sensor) shows a reading below 5 Deg C; implying the Frost Protection strategy has failed.

Outside Sensor Failed

This Alarm is generated when either the locally wired thermistor sensor fails (to open or short circuit), or if a Networked Outside Sensor is used, the alarm will be sent if this device fails.

Frost Protection in Progress

This Alarm is generated when Frost Protection stages 2 or 3 are in action, running the pumps continuously.

Local Indication of Alarms

Alarms are indicated by red flashing of the Temperature Indicator (Thermometer) LED. STOP alarms are differentiated from other alarms by flashing the thermometer LED amber and red alternately.

System Housekeeping Functions

In a conventional Wet Heating environment, the Boiler Controller performs several important housekeeping functions for the rest of the system.

Firstly, it contains the real-time clock, which broadcasts time-of-day and day-of-week information to any modules that may need it. The clock may be set from any Zone Controller, and the time information is backed up by a Capacitor, which means that the correct time is retained for a minimum of 8 hours in the event of power failure (providing that power has been applied for at least 1 hour).

Secondly, it broadcasts Outside Temperature to any other modules that may need it; it acquires the temperature either from a sensor directly connected to its input terminals 15 and 16, or from a Networked Outside Temperature Sensor. In the absence of both sensors, it will transmit a default value of 0.1 DegC lower than the Frost Setpoint (FRST).

Thirdly, it performs an important role in the unique SeaChange Registration process; it is responsible for the automatic allocation of system addresses during registration. It also keeps track of all Registered Controllers, so that if one of them fails, a replacement will be automatically allocated with the address of the failed module. This automatic feature may prove troublesome when commissioning large systems, so it can be disabled using parameter RPLN. When Commissioning is complete, the automatic mode can be re-instated. For further details, see our ‘Design Guide’ publication.

Secondary Boilers - No Housekeeping

In systems having 2 or more independent sets of boilers, (e.g. Campus installations with multiple Boiler Houses) Boiler Controller versions / NH / with No Housekeeping must be used. These controllers are supplied with the System Housekeeping functions disabled, to avoid conflicts with the Boiler Controller versions / SH / with System Housekeeping. Thus, in a system with 3 independent boiler plants, we would use 1 Boiler Controller version / SH / with System Housekeeping, and 2 Boiler Controllers / NH / with No Housekeeping.

Note that the Boiler Controller version / NH / with No Housekeeping can have a maximum of 2 Boiler Cascade or Actuator Submodules and 1 Pump Changeover Submodule registered to it, see Submodules section.

Multi-Domain Systems

Large systems may need to have their networks structured into more than one Domain. Boiler Controllers in a Multi-Domain system will require setting of the DOMN parameter, see our ‘Design Guide’ publication for details.

Commissioning

Setup Mode : Timing Characteristics of the VT Valve

It is possible to set the stroke time for the VT valve using pushbuttons.

Raise/Lower Types - Setting Stroke Time

1. Hold down Select until Temp lamp flashes
   Temperature indicator will flash red at one second intervals.
   Release select button; VT valve close output will energise to close valve.

2. When valve is closed press Select
   Temperature indicator will flash green and VT valve open output will energise to open valve.
   The controller is now measuring the stroke time.

3. When the valve is open press Select
   Flashing will stop and stroke time is now set and stored in non-volatile memory. This time will be retained until the procedure is repeated.
   

Note: if a Stroke Time of less than 30 secs is set using pushbuttons then the setup process is aborted. Temp indicator flashes amber rapidly for 5 secs indicating an invalid period. This allows checking of wiring without affecting Stroke Time setup. Stroke Times less than 30 secs can be entered manually via Zone Controller or InSite tool using parameter PERD.

Manual Override

Allows the outputs to be exercised during commissioning and maintenance activities. Holding the override button pressed until the Status Lamp flashes green will cause the controller to be switched from automatic control to Override Mode.

1. Hold down Override until Status lamp flashes
   Controller changes to Override Mode and simulates 50% Zone Demand, allowing boilers to control to Weather Compensated Setpoint.
   Useful for commissioning in summer months.

2. Press Override again
   Controller cancels Manual Override and reverts to automatic control.
   

As this feature does not time out, care should be exercised to ensure the module is returned to the automatic mode on completion of the commissioning or maintenance activities.

Occupancy Override can also be achieved via Doorway and InSite; using AUTO and OVRD monitoring parameters. The status lamp indication shows a different sequence.

Override from Off to ON : Status lamp flashes long ON, short Off
Override from ON to Off : Status lamp flashes long Off, short ON
See our ‘Design Guide’ publication for details of the Override features.

Hand Control

A new control mode has been added which allows Doorway to select manual HAND, this is activated by setting switch 5 HAND. The forces the controller to manual mode and the output of the VT loop is defined by the value on the config variable MANL. On this controller only 0 to 100% has significance because the Boiler controller only has heating. The Boiler sequencer will run the number of boilers needed to maintain the Flow temperature.

The process of selecting HAND and setting the manual level can be associated on the same point by using the following Doorway syntax.

[B1]W5(S)/hand/auto/12/10/C83(V) assumes the controller is Boiler 1

Clicking on the point allows selection of hand or auto and also the means to set C83 which is the manual level required.

InSite automates this process with it's Override features.

Registration

Registration is the simple process by which logical connections are made between Controllers in a SeaChange system; it is done during commissioning and involves pressing buttons on the Controllers in a specific sequence.

For further details of the registration process, see our ‘Design Guide’ publication.

Address Allocation and System Housekeeping

Boiler Controllers versions / SH / with System Housekeeping provide the System Housekeeping service for the whole SeaChange system. See our ‘Design Guide’ publication for a full explanation of this feature. The Boiler Controller keeps a Database containing the module addresses that it has allocated. Boiler Controllers with System Housekeeping are factory-set to address H1 (B1 also works with Doorway pages), and do not need to be registered to obtain an address. If the Register button is pressed, nothing will happen.

The maximum number of main modules that can be registered to a Boiler Controller with System Housekeeping are:

Address Class

Boiler Controller versions / NH / with No Housekeeping must be registered in the normal way to the SeaChange module that has System Housekeeping. The Boiler Controller with No Housekeeping will be allocated an ‘H’ class address by the System Housekeeper, see our ‘Design Guide’ publication.

Check that you have an appropriate System Housekeeping module, see our ‘Design Guide’ publication.

Interconnects

The Boiler controller must receive signals from a Zone Controller, or another Energy Consumer (e.g. Fan Coil Controller) or Distributor module (e.g. Secondary Circuit Controller). It may also send signals to other modules (e.g. a Pump Changeover submodule to control twin pump sets).

These Interconnects are put in place by Registration; again, see our ‘Design Guide’ publication.

Options and Product Codes

Boiler Controller for Medium Temperature Hot Water Control (MTHW)

BLR / DIN / MTHW / [housekeeping] / [driver option]

This product is available to special order only : please contact smartkontrols for availability

Driver options

SC Controls Ltd

PO Box313
Wadhurst
East Sussex
TN5 6JL

phone 08707 606040
fax 08707 606041
e-mail seachange@sccontrols.co.uk
http:// www.seachange.co.uk