DuoTherm Furnace

[morlach]

I have been updating some fittings and resealing them on my built in propane tank and have been running on an external 5-gallon tank. This morning I tried to use the furnaces. They seem to be functioning normally, other than the fact that they will not light. Is it possible that the external tank is not delivering enough pressure to activate the gas valve? I will be getting the main tank refilled pretty soon, but was curious as to what could be causing this. Thanks.

[Mike1997]

This is a 2 year old post but thought I would add a comment.

My 1997 LY diesel came with electric heat in the roof units and a large furnace that also heats the holding tanks. The Airstream was used mostly in Florida and trips to the Carolina coast. After I bought it last April, I took a job transfer to Montana. On arrival the furnace would not operate longer than 10 seconds. Turned out the computer board was bad. Many plastic parts tend to deteriate after about 10 years. Tech was shocked when he looked at the furnace and discovered it had never been used.