RV Repair: 1986 prowler furnace, propane torch, propane regulator

Question
My husband and I recently had the furnace checked in our 1986  24' Prowler travel trailer and they said it checked out fine. We recently tried to light it with no luck. We turned on the gas at the tanks, turned on a valve in the outside panel and there was gas to the stove. We held in the switch at the "pilot" position with the thermostat on and blower running and pressed the "light pilot" switch. No luck...  Do you think we are missing a valve somewhere?

Answer
It sounds to me like you are going about it wrong. First light the stove and let it burn for about 30 seconds or so in order to pull any air out of the propane line. Then you need to keep the thermostat off and hold the pilot switch in and strike the igniter. This may take several tries. There is usually a cap on the front of the burner housing that you are able to take off to visually see the flame when it is lit. There are some furnaces that only have a small hole to view it from. Remember that you are trying to light the pilot and that it takes alot longer for the propane to get out from that orifice because of the size. If there is a valve on the furnace it would be located where the propane line comes in to the furnace. If you are still having trouble, and there is a cap that you can remove then you might try taking a propane torch lighting it and sticking it in the hole while the thermostat is on and you are holding the button down as well. The pilot light has to heat a thermocouple enough to cause it to produce voltage which is what keeps the pilot lit by holding the plug in with a magnet. This last thing I told you to do should be done with care and only if all else fails. One other thing I should ask is were you in higher elevation when you tried to light it? If so it may very well be your propane regulator not allowing the correct amount of pressure to the unit. A manometer will tell you what the pressure is and you want it to be 11 water column inches at the appliance with no more than 1 inch of loss when you turn on all the appliances in the coach. That is the ones that use propane. It is one of the more dangerous systems in all coaches and should be respected.Thanks, Bill