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Anyone out there have a 376THS or even a 376TH and have used their furnace? I am very concerned as it relates to the furnace being able to heat the rig. Mine runs nonstop and can barely maintain ~60 degrees when the outside temp is in the 40's? Am concerned there is too much piping for this unit.
Mark
2014 HDT Volvo 780 "Baby Bird"
2016 Smart Car "Baby Bird Turd" - on the back
2020 Momentum 376THS
We're both proud USAF Retirees...
Retired RV Tech
Hmmmm! We have a 2017 376TH and spend the winter at ski resorts. Mean temp when it's single digit outside is around 65, and the furnace runs a lot. Only 40, you should be able to get internal temp up to 70 and not run all the time.
So something is wrong.
Two known problems. First one of the vent covers on the furnace unit got loose and fell off. They don't use all of them, plus, maybe one of the hose attachments came loose. This becomes the point of least resistance and allows all of you hot air to blow into the interior area where the furnace is. In my 376th can open the middle drawer in the hutch and someone has cut an access hole that allows me to peer into the area where the furnace is. See if that area is really warm. If you can't access it that way you will have to remove the barrier wall in the front compartment to access the furnace, that's the best way as you can crawl to the furnace and inspect it.
Second known problem, a hose gets kinked or crushed. Mostly you can just remold it by hand to get the air flow going.
You can make a home made breeze checker by tearing a strip of tissue paper about 1/4" wide and about 4" long and tape it to the end of a pencil. This is not an exact science, it just has to move when you blow on it. Hold next to each vent and see how strong the airflow is. Vent on the steps should be the strongest and the one in the bedroom the weakest, but they should ALL have airflow.
Stick a cheap thermometer in the vent and see what temps are coming out.
The most common problem I have heard of is a vent cover falling off, the screw is generally laying around someplace close.
That's the supply side.
Heat loss - Take a few minutes to look at all of the slide seals and see if there are any big gaps. Check the seal on the over head vents, that sometimes gets bunched up and lets the heat out.
These things are not the warmest and most of the time I end up using auxiliary electrical heat. Little cube heaters, the fireplace, and we have a medium room sized electric heater that we run in the kitchen.
2017 Momentum 376, 2019 Ford F450
2022 Triumph Scrambler Motorcycle
E-bikes, Hobi Pedal Kayaks
Kota the dog and KC the Kitty Cat
To add onto what Dallas (d2reid) said, sometimes a vent attachment point will come loose. His homemade airflow detector and the thermometer should help detect this. Here's a photo from my old 2014 337 where a vent pipe connection point failed.
Jim and Ginnie
2024 Solitude 310GK
GDRV Technical Forum Moderator
GDRV Rally Support Coordinator
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