Have RV Questions? Ask an RV Mechanic Online.
The most common problem when this happens is the control board. In later model furnaces the timed delay relay is on the board and goes bad frequently as these OEM boards are made in China and pretty much junk. Take a look outside and tell me if you have an outside inspection panel over the furnace exhaust or not. IF so, you can access the board from there. IF not, the furnaces has to be pulled out. This can be a bad relay in the ceiling box control. What is the make of your A/C and thermostat? That would help me direct you in some testing. All follow ups are included in our fee.
Just checking back to see if you were able to get this resolved or do you still need some help in sorting this out?