I've had my furnace for 5 to 7 years now. I bought it when it was two years old, after having served as the heating source in a green house for that time. I completely dissasembled the furnace when I bought it, cleaned everything and reassembled it. Sometime during those first two years, a furnace tech bypassed the vacuum switch. I've left that switch bypassed and have been using it as my primary heat source in my home. I burn 4 to 6 tons, depending upon the winter.
I've had no issues with smoke in the pellet bin or anything else other than the usual ignitor replacements, till last spring when I developed a new problem. It's a 5 blink code. This problem only occurs when the furnace shuts down due to our kitchen oven heating the house adequately, or after our Honeywell, programable thermostat drops heat demand down to 67 degrees at night. At about 3 to 4am, I wake up to a house that is cold. I either go to the basement and run the dial on the furnace from auto, to off and back on again or, I shut off the emergency furnace shut off switch and turn it back on again. Either one of these two, does the trick. The furnace will begin lighting, fire up quickly and run normally. I wired the programable thermostat as Harman described and never had an issue till now.
I started by replacing the ignitor, which I think it did need. Then I replaced the ESP probe, thinking maybe this would finish the fix. But this is still happening. I'm not sure if when the thermostat clicks on and calls for heat, if the furnace actually goes through the process of lighting or if it just immediately goes to the 5 blink fault code.
Judging by the troubleshooting guide, the only thing left that could be causing this problem is the circuit board?
Any help would be appreciated.
Update, It's 12:07am. The thermostat dropped the furnace down to 67 degrees at 10pm. The furnace went into shutdown. It is now off. It is flashing 4. I checked the thermostat. The Honeywell states that the batteries are low. I changed them just now. I turned off the furnace, turned it back on and still have it flashing 4. We'll see what happens in the morning.
I've had no issues with smoke in the pellet bin or anything else other than the usual ignitor replacements, till last spring when I developed a new problem. It's a 5 blink code. This problem only occurs when the furnace shuts down due to our kitchen oven heating the house adequately, or after our Honeywell, programable thermostat drops heat demand down to 67 degrees at night. At about 3 to 4am, I wake up to a house that is cold. I either go to the basement and run the dial on the furnace from auto, to off and back on again or, I shut off the emergency furnace shut off switch and turn it back on again. Either one of these two, does the trick. The furnace will begin lighting, fire up quickly and run normally. I wired the programable thermostat as Harman described and never had an issue till now.
I started by replacing the ignitor, which I think it did need. Then I replaced the ESP probe, thinking maybe this would finish the fix. But this is still happening. I'm not sure if when the thermostat clicks on and calls for heat, if the furnace actually goes through the process of lighting or if it just immediately goes to the 5 blink fault code.
Judging by the troubleshooting guide, the only thing left that could be causing this problem is the circuit board?
Any help would be appreciated.
Update, It's 12:07am. The thermostat dropped the furnace down to 67 degrees at 10pm. The furnace went into shutdown. It is now off. It is flashing 4. I checked the thermostat. The Honeywell states that the batteries are low. I changed them just now. I turned off the furnace, turned it back on and still have it flashing 4. We'll see what happens in the morning.
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