I have a forced gas unit and it sometimes comes on twice. What I mean by that is it runs stops and kicks right back on again. I used to have a nest thermostat and was told get rid that one because not having common wire can cause that. I since put the original Honeywell thy came with house (only been here a year). I don’t know if this is normal when house is colder or is it a thermostat starting to fail and not catching right temp. Any ideas?
Heater coming on twice
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I have swapped the batteries and ive noticed its not all the time. Mostly at night and just heard it now during the day. I doubting its any connection because its not all the time. I was thinking maybe a thermostat starting to fail or could it just be not enough heat on first floor where its located to ask it to stop?
Check for an error on the diagnostic light. If no diagnostic code displayed then check for a constant heating call with your meter.
If you have a constant call and no error and the unit still cycles it could be a problem with the board. I’ve known Nests to cause damage to control boards in the past.
Whatever you do don’t start blindly replacing parts without first diagnosing the problem.
If you have a constant call and no error and the unit still cycles it could be a problem with the board. I’ve known Nests to cause damage to control boards in the past.
Whatever you do don’t start blindly replacing parts without first diagnosing the problem.
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Before delving into this too far be certain it's not just the blower that's coming back on.
You mean coming back on blowing cold air? Its another cycle of hot air like a normal operation. I think whatever it is its not reaching the temp on thermostat and overheat sensor cuts unit off. Because it hasn't reached the temp the unit comes back on. Correct me if im wrong?
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Replacing the parts without knowing the exact problem or the culprit will cost you a lot . So there should be a diagnostic first. Then repair the parts. The thermostat seems to be causing the problem.
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If possible, you need to set the run time after call for heat to be longer. If it's too short or non existent, the heat exchanger will cook off and re-initiate the fan until the heat level of the heat exchanger is below the set point for fan operation. That setting is often available on the furnace control board via some DIP switch settings. Perhaps that may be overridden by the Nest software settings. I don't have Nest to look and give a more informed opinion but double running fan cycles are usually actuated by the fan run/overheat switch attached to the heat exchanger..
You say you've "only been there a year". Was this a new build? Call the builder. If not, did you get a warranty with the house?
The error codes are often on a sticker inside the panel you remove to view the main board. You'll typically find the exact model number there as well.
Has anything recently changed like moving furniture for Christmas that may be blocking a return register? Did you change the filters with a "better grade" or different brand (reduced airflow)? Think of what is different from when it was working.
The error codes are often on a sticker inside the panel you remove to view the main board. You'll typically find the exact model number there as well.
Has anything recently changed like moving furniture for Christmas that may be blocking a return register? Did you change the filters with a "better grade" or different brand (reduced airflow)? Think of what is different from when it was working.
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