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Boiler Ignores Thermostat -- Keeps Running

Background: We have a Lennox Gas Boiler powering a vapor steam system. We have a Total wireless thermostat. Boiler is about 5 years old as is the thermostat.

Problem: The boiler keeps running even though the thermostat is not calling for heat (the receiver in the boiler room lights up when the thermostat is calling for heat). The vaporstat is cutting off the boiler but it keeps cycling on. Even if I turn the thermostat off, the boiler keeps running. We have not changed or touched anything on the system -- this just started a few hours ago when I noticed the house temperature was about 5 degrees above the thermostat setting.

Thanks for any help.


  • Ironman
    Ironman Member Posts: 7,085
    Try This...

    Remove the wire from the "w" terminal on the receiver and see if the boiler shuts off.  If it's a Honeywell, press the wire retainer on the terminal to release it - it's tooless.

    If this works, then you'll need a new receiver and stat. If not, Shut the switch off to the boiler and call a pro.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Mark Riley
    Mark Riley Member Posts: 3
    Thanks Ironman

    That didn't work so it must be the boiler. I've turned off the boiler, called the pro and started the fireplace!

    Thanks for your help.
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