Atwood Furnace Problems
I have a problem with the Atwood furnace on my 5th wheel (2019 Montana High Country )
It's an intermittent fault, usually happening about once every week. In the middle of the night, usually around 1 or 2 am, we'll wake up cold with the furnace not running. If we turn the thermostat off and back on, the blower will come on, blow for around 30 seconds, and then turn off without even trying to light.
So after this fault:
1) The furnace doesn't even try to light after switching the thermostat on/off, only the blower comes on briefly
2) If I go outside and take the cover off, the red LED has the 1-blink pattern.
Here's the weird thing. If I take the cover off outside, and flip the little master on/off switch off and back on, the furnace lights back up immediately and continues to work perfectly until a week or two later when the exact same thing happens all over again. It is ALWAYS solved by taking the cover off outside and re-setting the master on/off switch.
Things I've tried:
1) I thought maybe the control board was bad. I bought a new one (Atwood OEM), but the problem stayed exactly the same.
2) Instead of going outside to take the cover off, I tried pulling the 12volt furnace fuse in the fusebox inside the RV and popping it back in. That does NOT fix the problem, the blower just runs for 30 seconds and turns off. The only way to fix it is to go outside, and re-set the master on/off switch physically located at the furnace control board.
3) I purchased a new sail switch and limit switch, since the 1-blink pattern says it's a "limit or airflow" problem. I will try installing those when they come this week and see if that fixes anything. But if the limit switch were bad it seems really odd that flipping the master on/off switch at the control board would fix it (for a week or two), while pulling/replacing the fuse inside the RV would not.
It's also interesting that it usually happens during the dead of night - i.e. when it's cold.
Any ideas what's going on or what may be the problem?
Thank you!
Randy
It's an intermittent fault, usually happening about once every week. In the middle of the night, usually around 1 or 2 am, we'll wake up cold with the furnace not running. If we turn the thermostat off and back on, the blower will come on, blow for around 30 seconds, and then turn off without even trying to light.
So after this fault:
1) The furnace doesn't even try to light after switching the thermostat on/off, only the blower comes on briefly
2) If I go outside and take the cover off, the red LED has the 1-blink pattern.
Here's the weird thing. If I take the cover off outside, and flip the little master on/off switch off and back on, the furnace lights back up immediately and continues to work perfectly until a week or two later when the exact same thing happens all over again. It is ALWAYS solved by taking the cover off outside and re-setting the master on/off switch.
Things I've tried:
1) I thought maybe the control board was bad. I bought a new one (Atwood OEM), but the problem stayed exactly the same.
2) Instead of going outside to take the cover off, I tried pulling the 12volt furnace fuse in the fusebox inside the RV and popping it back in. That does NOT fix the problem, the blower just runs for 30 seconds and turns off. The only way to fix it is to go outside, and re-set the master on/off switch physically located at the furnace control board.
3) I purchased a new sail switch and limit switch, since the 1-blink pattern says it's a "limit or airflow" problem. I will try installing those when they come this week and see if that fixes anything. But if the limit switch were bad it seems really odd that flipping the master on/off switch at the control board would fix it (for a week or two), while pulling/replacing the fuse inside the RV would not.
It's also interesting that it usually happens during the dead of night - i.e. when it's cold.
Any ideas what's going on or what may be the problem?
Thank you!
Randy
