Furnace won"t start. No problem vehicle. Furnace "hydro flame" won't engage. 1998 Palomino. New Battery drained down

Good Afternoon ,

The furnace runs off of the battery so if the battery is totally drained it wont start .

The shore power should charge the battery when its plugged in , if its not plugged in the battery will go dead in a few days from the propane detector or running the furnace will kill

Are you plugged in ?

is the battery still dead ?

does the fan come on ? what is the furnace doing ?

you want to check the battery voltage first if the fan isn't even coming on its either low voltage , bad thermostat or a bad blower . until the blower starts the furnace wont even try to light

then the thermostat is just an open and closes switch it just connects the 2 wires to the furnace .

if it is sending 12 vols back to the furnace , then you need to start troubleshooting the furnace .

you can find service manuals here .

https://techsupport.pdxrvwholesale.com/products-category/atwood-hyroflame-furnace/

It probably doesn't need to be replaced , worst case scenario would be a bad control board which may be $150 ,

new furnace is probably(###) ###-####depending on the size

you are welcome