2021 Avalanche 390DS no heat to bedroom

[Bemmert74]

The floor vents to the lower bedroom is not blowing air at all. We closed off living room vents to see if we could push air and still nothing. Our question is how do we get to where the ducts are to see if it is disconnected or kinked? Where can we find a diagram of the heating system and ducts? Our daughter needs heat in her room. The upper bedroom and bathroom blow just fine as well as the living room.

[flybouy]

There are no diagrames of anything from Keystone. Is this a new issue or is it the first time you're using the furnace? I'm guessing the furnace is under the the front bedroom steps. Typically there are return air grills in the step risers. Typical setup is a central aluminum duct running down the center of the trailer from front to back. You can remove that diffuser and take a look down to see if the duct is obstructed.

[Bemmert74]

This is first time running furnace. Yes it is located under upstairs steps. The back bedroom steps down but no way to look under steps there. We don’t see any screws or anything to remove the steps.

[flybouy]

Other than looking via the floor register you would have to go under and remove the coroplasre belly to see the ductwork. Is the trailer still in the first year warranty?

[Bemmert74]

Yes still in first year and yes we could take it in, but it is hard plumbed full timer unit and shop is 1.5 hrs away. They will not come to us. So we were trying to see if we could get to the area to see if disconnected. I really don’t want to pack ip my whole rv to take it in.

[Laredo Tugger]

Originally Posted by Bemmert74

This is first time running furnace. Yes it is located under upstairs steps. The back bedroom steps down but no way to look under steps there. We don’t see any screws or anything to remove the steps.

Looking at the floorplan for your trailer I do not see any steps into the rear bedroom. It appears the bedroom is on the same floor level as the living and kitchen areas. Not seeing the trailer I could be wrong.

https://www.rvusa.com/rv-guide/2021-...-390ds-tr50417

The advice in post #2 is the best way to expose your heating systems connections. The coroplast is not difficult to remove, it's just not in a convenient location (under the trailer). If you want to self diagnose and fix, I would get under the trailer with the heater running and feel for warm air escaping out of the coroplast. If you find an area in question use vise grips on the pin used to mount the coroplast. Twist out the pin and then replace with a large self tapping metal screw (being careful of electrical or plumbing lines with screw travel ). If you are unable to get under the trailer and not comfortable with the tools mentioned, and towing to the dealership is a burden, I would recommend a mobile RV tech. You could check with your dealer if they will authorize warranty service off location by someone not in their "certified" inventory. Not sure how that works but it couldn't hurt to ask.
Good luck
RMc

[JRTJH]

There should be other vents along that central aluminum duct that deliver air as the duct goes toward the bedroom vent. Is air blowing out of all the vents along that route??? If so, there's probably a connection close to the bedroom vent that came loose.

If there is no air along the entire route, then there's probably a connection that came loose "ON THE FURNACE DISTRIBUTION BOX" that's connected to the furnace air exchanger.

I'd first confirm air flow from the other nearby registers. If there is NO air flow, go to the furnace distribution box. That's where your problem is located. If there is air flow along the route to the bedroom vent, then remove the vent cover on the bedroom vent, use a flashlight to try to identify an opening without a couple feet of the vent cover because the disconnected hose is close to the bedroom vent.

[JRTJH]

Originally Posted by Laredo Tugger

Looking at the floorplan for your trailer I do not see any steps into the rear bedroom. It appears the bedroom is on the same floor level as the living and kitchen areas. Not seeing the trailer I could be wrong. ...

If you go to the Keystone RV website and look at the 3-d depiction of the trailer floorplan, you can see that the rear bedroom is a "step down" into the room. You'll need to go to this link: https://www.keystonerv.com/product/a...oorplans/390DS then navigate into the rear bedroom, arrange the view to be "looking forward" and you can see the steps that the OP is referring to in his posts.

[Laredo Tugger]

Well there you go.
Offers more " headroom " in that bedroom. Makes sense.
Learn something new everyday.
Problem is remembering it.
Thanks John.
RMc

[flybouy]

Originally Posted by Laredo Tugger

Well there you go.
Offers more " headroom " in that bedroom. Makes sense.
Learn something new everyday.
Problem is remembering it.
Thanks John.
RMc

I think they dropped that section to fit the "loft" above it.

[markcee]

Doesn't Keystone approve warranty work using a mobile RV repair service on a case by case basis? Worth a call to them at any rate, given the circumstances.

[Db361]

We have a similar issue with not only rear heating vents blocked but also the front bedroom. Only heat is in center area of RV. In addition there is no A/C air flow to back bedroom or bathroom. I found heating ventline to rear bedroom crushed. RV is currently at Dealer being repaired. A/C will probably require an air flow booster fan.

[jimborokz]

Assuming you have air flow in the living room vents and none in either of the bedroom vents my bet is on a restriction at the bedroom step.
I recall a while back a post that had a similar heat problem. Don't recall if it was an Avalanche or not but the problem was the heat duct that ran the length of the trailer necked down to a very thin section to clear a cross frame or something and was restricting the air flow.
My guess this is a similar issue.

[DC&J]

I have the same issue we just bought ours feb 6th and received today after having the dealership look into it. They said the duct was kinked and fixed. However once I got it home it was the same minimal heat and a ton of flow in the living room. I read some options below and will try to see if the ducts are opened

[TLStrickland]

It is interesting. That keystone has the heating ductwork problem. Yet they install un dampened registers in the whole unit. Including the pass through heat vent. There is definitely some build tolerance differences coming from the jayco side of the family to the keystone side of the family.
Interesting part is you can install magnetic covers on all the kitchen, front bed and front bath vents. Tape off the vent in pass through. And the heater barely blows in the back. It’s going somewhere or the furnace would over heat and shut down.
I like the floor plan. But heating and cooling the back received no engineering at all. One cooling vent even with 3 ac units is a joke. This engineer here could poke some sarcasm at Thor/Keystone engineers.
They could have kept straight ductwork and put the vent in the rear step. Then a duct from there to bathroom. Interesting to say the least. I guess the end user has to do all the R&D work for keystone.
Don’t take me wrong. The Jaycos have issues as well. Cosmetically the keystone is a nicer looking rig. But it’s obvious they put lipstick on a pig. But then it’s still a pig. Heat worked fairly well at dealership. But 100 mile drive home I assume the duct is smashed now.

[Gearbox5]

My 2021 had the same problem but I fixed it. If the heat is blowing to the rear vent on the living room floor with good force but nothing is coming out the rear bedroom or bathroom, it is a couple of things. Starts with the poor quality, sorry, [and hey, we still love ours!] and poor materials. Take off the rear living room vent and the first one in the rear bedroom. Take a flash pic with your phone and in each case you will see a 4 inch round flange sticking up. Not good for decent airflow. From there they hooked up a 4 inch round flexible silver vent pipe like a "U" to connect both round flanges They had to drop this pipe down to CLEAR the two large metal bulkheads [you can see from the outside just before the slide] as that is where the rear is assembled to the main mid coach. Forget the stairs, nothing to do with this! My rear end of the flex heat pipe, that was supposed to go up and connect with the rear adapter the sheet metal "experts" put right by a metal crossmember and they jammed it on, but it was flattened like a compressed slinky pushed sideways. I moved the flex pipe where it attaches to the rear vents around to the other side of the crossmember and have just enough room to put the flex hose on. You have to go thru the bottom. Either remove that section of bottom cover completely, but some people cut a small 3 sided flap app. 2 ft from the right side and app. 18 inches from the bulkhead. You will see the issue right there. Also the sheet metal "experts" hammered each end of the vent flat pipes to seal them. No problem, but look at your pictures you took. Does it look sealed up back there? This will depend on how good the "craftsman" was. Bottom line is to take off both rear covers and put good sheet metal and decent adapters on the system. Fixing it like I did mine works, but each unit will be a little different due to inconsistent mfg processes. I looked at my friends 390 and there are differences Oh, warranty? snicker, snicker. I was told you have to do a certain amount of, as the ole boy true expert told me, of "piddlin'"most every day. I am no expert, and I am not suggesting anyone to do anything, but this might be your problem. We love our 390 and have had it all over the country. Good Luck! Be safe!

[TLStrickland]

Yes sir agreed. Will get it sorted soon. I have an interesting email exchange with keystone and thor. They deny there is a problem with their units. They should recall all of them and fix them. Ineterestingly look at Jaycos compareable product. More ducts and adjustable registers on heat and ac in the back and whole trailer. Im kicking my *** for not trading for another Jayco, same company but better built for sure. This is a nice unit though. Will get it right and enjoy it. Thanks!