I got it to work, no access panel required.
The propane furnace is controlled by the thermostat. For the furnace to turn on you need propane coming into the RV from the tank and you need good DC battery voltage.
Then you would turn the thermostat on, select the heat or furnace option and raise the temp what should happen is the blower motor for the furnace will kick on and several seconds later the furnace will fire off.
IF you are doing all these steps and nothing is happening please send me a photo of your thermostat, you can add photos into your reply using the paper clip icon on the page.
Robert
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