I had the camper unplugged most of the winter from the battery. Ended up replacing the battery earlier this year when I determined it was bad. When I plugged everything back in last week I heard the furnace running. So pulled the fuse on pos cable until I could get it popped up and investigate. Double checked and made sure thermostat was clicked off. The furnace just blows constantly as soon as it has power. I tried turning thermostat on to run a cycle, wouldn't ignite even after filling lines by igniting stove. My hvac buddy thinks it may be in a perpetual "cool down" mode. I plugged into shore power and let it run a long time but still persists. Another tidbit is when I have the fuse (at panel) pulled a red light lights up. Don't know if that means anything or not. I think that is everything I have thought of/tried so far. Any thoughts?