Atwood Furnace Quit Working After Install Of New Advent AC Plug & Play

Updated 12/02/2021 | Published 11/28/2021

Question:

I recently replaced my 2006 Ragen 5th wheel Dometic 13,000 btu AC unit with an plug and play Advent unit we purchased from etrailer. A few months later i.e., after it got cold, we tried running the original Atwood 8531-IV DCLP furnace. No joy. It worked the previous winter but the next time we ran it, after replacing the AC, the furnace motor wont start. We bought a new furnace board. No joy. Ive get power at the furnace on/off swtich and thence to the board but no power from the board lead to the motor. I ran the motor directly from the battery and it runs fine and I hear the sail switch flip down. The Dometic 3316250.700 Single Zone thermostat runs the AC fine. When I set it to furnace I hear a click up near the AC. Can you please describe how the thermostat relates to the grey box in the AC plenum source of the click when I set the heater thermostat to on and thence to the heater and how to confirm if its sending signal to the furnace. Now, there are two lead receptacles in that grey box with no wires going to them, but to my knowledge I did not touch any of the HVAC wires during the AC switch out just the power harness on the other side of the grey box. And the empty receptacles dont show current when the click happens or at all actually. In short I dont think I did anything during the AC switch-out that would have affected the furnace operation from before when it worked all the HVAC wires seem to be installed in the other receptacles as before. Thanks

asked by: Terry W

Expert Reply:

The different brands of appliances are not communicating with each other. I know this can seem flabbergasting, why would companies make things different! The # ACM135 is not design to work with a wall mounted thermostat.

I recommend going with the Air Distribution Box w/ Wall-Mounted Thermostat for Advent Air RV Air Conditioners - White # ACRG15. This will replace the wall thermostat and get rid of any issues and promote good reciprocity between the appliances.

I have added a diagram of the air box wiring to help.

expert reply by: David B