mobilehomerepair.com

Hi there, I tried to do as much of my own research as possible before posting this to refrain from posting yet another "oh no its broke" topic.

I have a Coleman Evcon DGAT070BDC furnace/ac that is failing to properly ignite the burner, at least from what I can tell. During its sequence the Thermostat calls for heat, the draft fan starts up, few seconds later the Hot Surface Ignition fires up and stays red for about 10 seconds or more, then the HSI shuts off. The furnace tries this indefinitely I believe.

I am at the point now where I am out of guesses, I don't actually see the burner fire up then shut off so I am unsure if the flame sensor is to blame or what is happening. Any ideas?

You could always clean the flame sensor with a bit of steel wool. But if it's not even lighting, then check and see if you are getting power to the gas valve during that period of the start-up. If you are getting power, perhaps the gas valve isn't opening and you need a new valve. If you aren't getting power, then look for a faulty limit switch.

Mark