New NT30 is NOT keeping us warm!!

[obxgal]

I wrote in a couple of weeks ago telling how efficient the new Suburban NT30 furnace was in our '75 Excella...when 30F it nearly blew us out and we had to keep the thermostat down on ~67F.

We're finding out that is not the case when the temps go below 30...in the 20's the furnace struggles all nite and the air coming out is lukewarm. In the teens it keeps the temps inside at about 62F inside...and folks, when you're not moving, that's COLD!

Are we doing anything wrong? We are having to use an auxilliary heater which helps a lot, but shouldn't it be able to heat us down to the teens?? Did we replace it with too small a unit? (it was what I read in the forum as the correct size to replace our unit...) I could understand if it was below OF, but it seems it shoudl at least get us up to 70F.....

Any experience with using your furnaces in the winter???

[overlander63]

The 30,000 btu furnace is what came in your coach. How are your door and window gaskets? Have you replaced them? Another biggie is the access compartment gaskets under the beds and under the bathroom sink in rear bath models.

[obxgal]

Rick has replaced gaskets and sealed it nice and tight...we rarely ever feel any air movement from outside, even when sleeping up in the living room on the sofa bed...he even insulated the chute for the gas refrigerator as we aren't using it on gas....(that made a HUGE difference...a lot of our heat was rolling right up that chute!)

I really don't think it is a matter of air intake as much as the furnace not being capable of outputting enuf...but I do not know at waht point I am straining the thing. I can't find any specs that tell us "most efficent between "X"F to "X"F.

I'm hoping someone in here has camped/lived in the teens with this model furnace....

[obxgal]

I think I figured out a lot of Rick's problem last week...he failed to mention that the wind was whipping along at 30mph at the time! That, and he has not installed any underpinning.... He's parked in an elevated field that is indeedy a windy site...so I guess that poor furnace did have a rough time! It just didn't make sense as while I was there Sunday it semed fine. I'll be heading up on Friday as soon as school gets out (quickly, please Lord!!!) and see for myself how it's doing, as a big wintry front is heading in that direction on Saturday.....nothing like testing it out firsthand! It'll be a white AS Christmas????
Susan

[overlander63]

If the trailer is going to be parked in that spot for a while, it would help to place some hay bales or something similar around the bottom to help keep the underbelly drafts to a minimum. You'd be surprised how much a wind break can help. Just keep them away from possible sources of ignition (duh).

[Lothlorian]

My wife made thick insulated curtains and she also designed and made cushions for the vents. The curtains especially made such a world of difference. We had the trailer out in 26 degree weather and we stayed very warm. The furnace did not cycle that much. My furnace is a new 30,000 BTU. The trailer is 27'

When we opened the curtains we could feel the cold coming off the windows.

Try getting some good insulated curtains.

Brian

[genearnold]

We’ve had some sub-zero temps on the Oregon border where we are spending about three days per week working part-time. In October I installed some home-made skirting I made from some 1” Styrofoam insulation board. I was pretty careful to seal it with duct tape and make sure it is tight at the ground. This is doing a pretty good job keeping the floor comfortable. Our trailer is newer than yours and we have two propane furnaces plus the two A/C units that have heat strips. We also use an electric ceramic heater. However, we seldom, even when near zero, use the propane units as the rooftop A/C units, along with the ceramic heater, keep it pretty comfortable. On the coldest mornings I’ve been using the front propane furnace to bring up the temperature when I first get out of bed. My main purpose for having the ceramic heater is to leave it running on those days when we are not living there. So far it has kept the unit from freezing (we’re using the water and hoping for the bestJ). Last week when we arrived in late afternoon with outside temps in the low 20s the trailer was 45 degrees inside.

FYO—We have heat strips on the supply hydrant as well as the line to the trailer. When I leave I disconnect at the hydrant and drain what I can out of the supply hose and also unplug the electrical supply to the strip on the supply hose. Also, we leave the bedside cabinet door open as well as the bathroom and kitchen cabinet doors. We’ve had a couple of glitches relating to the attachment points. Once because I had not disconnected the hydrant end and again when I hadn’t drained the hose well enough. Solution involved peeling back the insulation a bit and using my wife’s hair dryer on these points.

I have an improvised cover made of 2” styro that I secure over the water heater access door. Before securing it I place a lighted bulb inside the compartment. So far, so good! I forgot to mention that I have adapted and secured a faucet cover (you get them at any big-box store) over the city water entry point. It is just the right size.


Of course, none of the above will matter if you are boon-docking!


Gene

[Jammer]

Originally Posted by obxgal

I wrote in a couple of weeks ago telling how efficient the new Suburban NT30 furnace was in our '75 Excella......shouldn't it be able to heat us down to the teens??

NT30 is 30,000 BTUs in. I've never seen an efficiency figure published but I'm guessing 60%, so that's 18,000 BTUs out. Not much in the teens and wind.

The funny thing about heat is that barely enough is just fine and you'll never realize you're on the edge. Not quite enough and you really notice it though.

[Andrew T]

Hi Suzan & Rick

The ductwork in 77's was not very effiecient. You will notice it runs along the wall with lots of air leaks so very little heat reaches the back of the trailer. If you have a side lounge the duct to the front of the trailer is also pretty restricted so the furnace does not breath. On some the furnace was inside boxed area with very poor return air flow as well.

If you make sure it has lots of return air and add a another outlet you will find it works much better. You will likely need an electric heater in the back end however.

Andrew T

[LI Pets]

I have the org heater, but I took out all the old heavy ductwork.

I put in insulated round vinyl duct work.

I was in 20 degrees all was good.

Check the front door is closed tight and all joints.

There is also a flame adjustment, did you check that?

[Aage]

Susan & Rick,

A couple other posts have mentioned the ductwork. You don't mention what layout you have, but I know that in mine (rear bath, mid twins) as Andy said, the ductwork tends to leak a lot of air along its path to the rear bath.

I discovered some holes in the metal ductwork, round, about 3" in diameter (at least two I have come across) that were created either at the factory, and have been left open by the OP, I'm guessing. On one (under the curbside bed) the disc that was removed was just loosely sitting on the ductwork partially covering the hole. The one under the galley sink was taped shut.

Also, the joints in the ductwork were originally taped with some kind of tape that looks like paper. Of course, in time, these paper patches on the joints loosened, and now leak like crazy.

Finally, when I removed the trim rail and wood skirt in the front of the bath tub, I found that the ductwork connection there was again (and I would say intentionally) left loose and leaky, with another opening cut into the top of the duct just where the duct joins the register .

The only result of all this that I didn't appreciate was that the bathroom was always cold, since very little air actually made it out the register.

I felt that the factory's original intention was to allow the places beneath the kitchen cabinet, my (curbside) bed, and the bath tub to have some heat.

My objective was to warm up the bathroom a bit. So, I cut a piece of metal to block the cutout in the ductwork near the bath tub register, and wrap the register's tail (that fits into the duct) in thin foam to block most of the air leak under the tub.

Just this made a big difference in the bathroom comfort.

I wanted to keep the spaces under my bed and also under the sink warm, and so I stopped there.

To cut to the chase: I would add adjusting your ductwork's outlets, both visible and hidden, to your job list to warm up your coach.

You could easily direct more heat into places you want it, with possibly dramatic improvements to your situation.

Get a roll of tape and maybe warm up!