Just Got A New Coleman Furnace...Now I'm Freezing

[SueAnnK]

There was NOTHING wrong with the old one (original 1987 Coleman 7966-856 -- 66,000 input 53,000 output) except annoying metal expansion noise and surface rust. But a leak caused buckling of the floor under it, and we had to take it out to fix the floor. I decided it was as good a time as any to replace it. The noises drove everyone crazy, but never once was the trailer cold. I had a new Coleman DGAA070BDTB 70,000 input 56,000 output installed, and it cannot heat my trailer above 60 degrees in average weather for winter in the Pennsylvania Pocono mountains. On colder days it runs continuously and totally wastes propane. Even adding electric space heaters is not enough. My installer says this size should be fine for my 13' x 70' trailer. I have not yet called the authorized Coleman repair. The guy who "fixed" the floor did not remove the buckled floor (it had pretty much flattened out after drying) but added a piece of 5/8" plywood over the old floor. So the new furnace is sitting about an inch higher than the old one. I have also noticed the blower on the new furnace is stronger than the old one which worsens cold air entry into my "mature" trailer. But honestly, it just seems the new furnace does not have the BTU strength of the old one, despite matching specs. What if my installer forgot to do the natural gas to propane conversion? Wouldn't that lower the air temperature output? How would I know? What else could be going on??

[Robert]

Hi,

I would get the installer back out there and have him resolve the issue immediately. Measure the return air temp at the furnace return air door grille.

Then measure the supply temp at the closest supply register to the furnace.


Subtract lowest from highest to get temp rise.

Look on the data sticker or nameplate for design temp rise and see if yours matches or is around midway point where it should be.


Thanks,
Robert