Heating, Air Conditioning, Fridge, HVAC/Gas Furnace Won't Turn Off


Help!  My 1-year old Climatecare (Johnson) gas furnace won't turn off.  I've replaced the Honeywell programmable thermostat (rth7500d) 5 times in the past month (3 times in one night, in particular) and I've changed the batteries every week in this most recent thermostat (7 times so far today).  The furnace seems to respond to the thermostat when I select "heat off" to turn off the system and will turn off (and stay off) but if left on, it continues to inaccurately read the temp in the house and hence, kick-on.  If I manually turn the temp down (e.g. from 70F to 68F), the number that reads the temp in the house also immediately goes down to the same number where I've reset the temperature (e.g. 68F) even though the house is still at 70F. If the thermostat does manage to turn the furnace on and off, it runs at odd cycles (e.g. runs for 30 min, shuts of for 3 min then, starts the cycle again) until the temp in the house is out of control. My dad is a retired electrician and has rewired the thermostat(s) to the furnace a few times already.  The odd thing is that the previous 20-year old furnace would act up like this once per year and just required new batteries in the thermostat but, this one started to do it in December and it's almost on a weekly basis now and isn't responding to new thermostats or batteries.  The only way to get it out of this cycle is to turn the system off for 6-8 hours.  The heating/cooling company is at a loss as well as my electrician dad. Help!!!

The batteries don't have anything to do with the furnace heat turning on and off.
What about the blower dose it follow the burner cycle?
There may be something heating or cooling the thermostat like a cold mounting place, a draft in a wall space, to close to a vent pipe space etc.  

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

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