We've had the technician out twice, and still no answer. We have a 4 year old two stage high efficiency furnace and it keeps overheating as soon as it hits the high-heat stage...so every 10 minutes since Winter started. Then it will cool down and restart the cycle, repeat in 10 minutes. The technicians are blaming poor returns and won't do anything unless that's fixed, but we think it's something else. The returns were poorly designed and we've been doing some construction that did change them slightly but not much. We get the 4 flash code when we first turn on the furnace and every time it overheats....however it didn't used to give us the 4 flash code, just when I switched out the filter and then in the last week....before it would just restart the cycle without the code. We've cleaned filters and the blower, and checked the limit switch. All are functioning. We're thinking it could be the circuit board...not sure what else it could be...
- posted
2 years ago