I suggest you download and read the manuals for the equipment in your RV (and home also). It could end saving you a lot of inconvenience, dissappointment, frustration and money.
Page 39 of the suburban furnace manual (my version, saved on-line as a convenient PDF);
"Cleaning of the main burner and an inspection of the venting system should be done at least once a year, preferably justbefore the beginning of the heating season. Some RV owners and service personnel have the false assumption that if afurnace has not been used, it will not require cleaning. NOT SO! A furnace which has not been used for some time couldbe more in need of cleaning than a furnace which has been used extensively.
Dust and lint should be removed from the room air blower wheel and sail switch. A build up of dust and lint on the blowerwheel can cause the motor to drag and not generate enough air flow to engage the sail switch. Dust accumulation on thesail switch will restrict the travel of the actuator arm and prevent operation of the valve circuit.
A yearly inspection should be made of all gaskets on the furnace. If any gaskets show signs of leakage or deterioration, they must be replaced."