Reddit reviews Honeywell Home CT30A1005 Standard Manual Economy Thermostat
We found 1 Reddit comments about Honeywell Home CT30A1005 Standard Manual Economy Thermostat. Here are the top ones, ranked by their Reddit score.
Heat only manual thermostatSimple worry free operationBimetal temperature sensorDecorative back plate included,Item does not come with an off switchMercury free
Based on your description, the thermostat is malfunctioning.
Realize all a t-stat does is close a switch in a 24vac circuit that tells the furnace to operate. Programmable t-stats just manage the switch to attain your programmed temps... but at the end of the day all it doing is opening and closing a switch (or switches if in the case of a/c).
Easily tested with a new thermostat. Buy and install a 'no-frills' t-stat. Something like this: https://www.amazon.com/Honeywell-CT30A1005-Standard-Economy-Thermostat/dp/B000BQWADS/ref=sr_1_6?s=hi&ie=UTF8&qid=1510432703&sr=1-6&keywords=thermostat
If the furnace now functions normally, then you've confirmed the the old t-stat was a POS and you can safely invest in a programmable or 'smart' one with some confidence it will work.
If the same problem occurs, then something else is happening and warrants a service call.