2018 Vintage Cruiser. When I turn on my heater thermostat the fuse blows.

[RJL]

I had to replace the circuit board on the water heater after I bought camper. I think I need to replace board on heater. Have never tried heater until now. We use a ceramic heater. Can someone tell me where the circuit board is located?

 

[THenne1713]

Not 100% sure, but believe thermostat wiring goes to a relay board mounted in a box up inside return air/ ceiling grill access for air conditioner? There is also 120vac there. If talking LPG FURNACE, it also has a board for gas control/ safety switches, Suspect thermostat wiring then goes from ceiling box back down to furnace. Been a few years since I saw mine, so maybe wrong. Furace is 100%-12vdc and no ACV on most. Exceptions may apply? Unclear if U Are saying permanent ceramic or portable?