turn the heat back on and then heat works fine for a couple days then cuts off again. I have to keep repeating the process. I have replaced thrmostat, circuit board and gas valve. Anu suggestions? Furnace is 9 yeras olds made by Solitare.
If you can watch the fire when the Blower kicks on and the fire leaps or distorts it could cracked heat exchangers they could periodically blow out the fire by blowing it away from the flame sensor causing the furnace to shut down, also I know the Goodman manufacture had problems with controller boards even new ones
There is no diagnostic light on a 9 year old furnace. You either have a high limit problem or a combination fan switch issue or a pressure switch issue. 88 Degrees is way too high if thats the temp your running it on. It will never shut off and just trip the high limits and then they have too cool down to self reset.
sounds like a faulty thermostat, they can be replaced and only last two minutes
