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pump control through zone panel or boiler panel?

i have the KHN085 boiler and the taco zone panel and zone valves.i have the tstats going into zone panel and zone valves also in the zone panel. there's an end switch terminal from the tstat terminal bar in the panel which i was going to connect to the boiler. i assume any tstat call closes that switch so it will tell boiler theres a heat call.
But i now have the boiler/system pump [its piped direct] wired into the boiler instead of the pump terminals in the zone panel. does it matter? i was thinking if the boiler gets a call it will run pump same as if the zone panel would do it.


  • SWEI
    SWEI Member Posts: 7,356
    If you wire the pump to the boiler, it will run a post-purge. Most are time-based, a few are temperature-based.

    ZCP may also have a post-purge time option of some sort.
  • keyote
    keyote Member Posts: 659
    thanks swei
  • keyote
    keyote Member Posts: 659
    but wait a second the taco zone panel wont run a pump conected to it until the zone valve is all the way open third wire, does that still happen when the pumps are wired to boiler? there was a terminal at the beginning of what seems like part of the thermostat terminal bar.which i conected to boiler heat call terminal . did i bypass the ability to wait for valve to be open by coming off tstat bars end switches? are there other end switches? that would be bad to start pump with valves closed huh lol