Furnace Help

[KRstrout1]

I have a 1981 Sunline 16 ft trailer. every time I try to lite the heater (dura flame furnace ) I get a puff of smoke or air out of the observation hole. I want too remove the heater and go trough it as this camper sat uncovered for 3 years before I bought it. so how do I remove the furnace, is it a two piece furnace ?

Ken & Robin Strout

[mainah]

The whole thing should come out check the exhaust vent make sure there are no bees nests.