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Wifi Thermostat to Boiler

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Hi,

New here, so please bear with me. I have an older Burnham Series 2, somewhere between 2000-2005, boiler supports an old gravity (1908 home) system. We had a plumber come in a few weeks ago, as the system seemed to be short cycling. He replaced the expansion tank and circulating pump (orig. taco), and cleaned the boiler. Anyways, we have a Honeywell T5 Lyric thermostat that has been working, ok, but not optimaly. It seems that the circulating pump only comes on when the boiler fires and shuts down as soon as the boiler reaches temperature. Trying to figure out if I wired the thermostat incorrectly (most likely) and how to correct it to run after the water heats up.

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  • Big Ed_4
    Big Ed_4 Member Posts: 2,785
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    Well ,it is not a gravity feed system if you have a circulator . What control did you wire the thermostat to ?

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  • HVACNUT
    HVACNUT Member Posts: 5,841
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    On the Honeywell control center in the boiler, R goes to R on the thermostat. G goes to W on the thermostat. C goes to C on the thermostat. 
    The circulator should run for the whole cycle until the demand is satisfied. Unless someone altered the factory wiring or added a B aquastat. The burner can cycle off and on through the limit, which is Y on the Honeywell control center.