User Guide

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© 2018 tekmar 301P
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D - 02/18
Sequence of Operation
Indicator LED Operation
DIP Switches
Zone Pump Operation
Boiler Operation
Power
• On when 115 V (ac) is applied.
• Off when power disconnected or transformer fuse is blown.
Zone 1
• On when the thermostat calls for heat.
•
On during pump post purge after the thermostat stops calling for heat and the Post
Purge DIP switch is on.
• Off when thermostat 1 not calling for heat and post purge expired.
Exercising DIP Switch
ON: Each circulator pump is energized for 30 seconds every 72 hours.
OFF: Circulator pump exercising disabled.
Post Purge DIP Switch
ON: After the last thermostat stops calling for heat, the last circulator pump remains
on for 2 minutes to purge heat from the boiler to the zone.
OFF: Post purge disabled.
When a thermostat calls for heat by closing the R and W terminals:
• 115 V (ac) is applied to the corresponding circulator pump.
• The corresponding zone indicator LED is turned on.
When the thermostat stops calling for heat:
• The pump is shut off immediately if the Post Purge DIP switch is off.
• The pump operates for 2 minutes if the Post Purge DIP switch is on.
When a thermostat calls for heat by closing the R and W terminals:
• The boiler end switch XX is closed to fire the boiler.