Watts tekmar 294 - Pump and Damper Operation; System Pump Operation Modes; Combustion Air Damper Operation

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IOM-T-294 2205 © 2022 tekmar
System Pump Operation
The control includes a system pump that can operate
whenever there is a call for heat.
Central Heating Call
The system pump turns on together with the central
heating call.
Domestic Hot Water Call
The system pump can operate in combination with the DHW
pump. Please refer to the Domestic Hot Water Call Operation
for details.
Setpoint Call
The system pump can operate together with the Constant
Setpoint Call. This is selectable using the Constant Setpoint
System Pump setting.
Remote Setpoint Call
The system pump operates whenever there is a remote set-
point call.
System Pump Purge
The system pump includes a post-purge after a heating call is
removed. The system pump post-purge operates with the last
boiler pump post purge.
Exercising
The control has the option to exercise all pumps and tekmarNet
zones (zone valves and zone pumps) for 10 seconds every
three days of inactivity to prevent seizure. This is selected by
setting Exercising to On.
Pump Operation
Combustion Air Damper
The combustion air damper relay closes once a heat call is
received and the control has determined that one or more
boilers need to be turned on.
Combustion Air Delay
The control waits until the combustion air damper delay elapses
before staging on any boilers.
Combustion Air Post Purge
There is a fixed 15 second post purge of the Combustion Air
Damper relay after the last boiler has turned off, or the heat call
is removed. If there is a call still present once the last boiler has
turned off, the control may continue to keep the combustion
air damper open if the control predicts that a boiler may fire.
Otherwise, the combustion air damper will be closed once the
15 second post purge elapses.
Combustion Air Damper Operation