Furnace

[scf31]

I am in need of furnace repair and need to know what I have, I cant read the I.D. plate, does anyone know what model and BTU Suburban furnace I have in My 1977 25 foot Caravanner ? Thanks

[Lumatic]

Take the front off and there should be a model number. If it is a NT22a there was a recall about 20 years ago. You will probably have a hard time finding parts or someone to work on it, Remember it's 33 years old. Would you want a 33 year old furnace in your home? I and others have replaced with a new NT30SP

[scf31]

I will be replacing the old one but dont know the size of the old one, to get a replacement,,,,,, Thanks

[Lumatic]

My Tradewind is a 25 footer. A Suburban NT 30 SP works well.

[ticki2]

Replaced mine with a NT 30 SP , almost identical , if I remember the wires come out on the opposite side , minor change . Pretty sure yours will be the same. Good luck

PS The original was a NT 32 FCA

[smaurer16]

1972 Overlander 27', I just replaced my NT30A with the NT30SP. I picked the same BTU, 30,000, because if you bump up BTU's then you need to alter your duct sizes. Looked like a big pain and if the engineers picked that size then it should work best for the square footage of the trailer. Simple HVAC math. Also the new units from Suburban are all updated for efficiency and electronics. The hard part is adapting for the original duct work/base but is doable in a days work and using the old parts/sheet metal from the old furnace.

[Aage]

If you're going to buy a new furnace (which I agree is the Right Thing To Do), be sure to have a look at the new 2-stage ones that Atwood is selling now.

To me they make a lot of sense, when you think of how fast a trailer will lose heat, and therefore force the furnace to come on more frequently than at home.

With the 2-speed model, it will come on sooner, but with a lower fan speed and therefore less noise, and better fuel consumption than the older single-speed models.

You should be able to save fuel costs (I know, big deal in a trailer), but more importantly, have a quieter unit on average. and be able to keep a much more even temperature in the trailer. Comfort. All about comfort.

Have a look here for more info. Yeah, they are a bit more to buy (not a horrible difference, IIRC), but they are the first real improvement in RV furnace technology in probably 40 years.

Like I say, at least take a look...

[Lumatic]

Originally Posted by smaurer16

if you bump up BTU's then you need to alter your duct sizes

I replaced my NT22a with a NT30SP as have several other members. Did not replace duct work and the old duct work handles the output fine.

[smaurer16]

I know that you can adjust the fan frequency on the Suburban thermostat too.

[Lumatic]

Originally Posted by smaurer16

I know that you can adjust the fan frequency on the Suburban thermostat too.

You adjust the fan frequency with the anticipator on the thermostat. Some thermostats have them and some don't.

I had a problem with rapid furnace cycling that was caused by a bad OEM thermostat. I got a El Cheapo Walmart thermostat and it solved the problem. Even if the replacement says it runs on 24v it will work with a 12v furnace.