Heat only out of one vent

[Bookum32]

I took my rv to a local RIP off after discovering my 2017 Kz spree didnt have air blowing out of 2 of the 3 floor heat vents. They did not fix the problem ( Charged me 6 hours labor to seal the furnace) I am not sure where to start, but it appears that there is some sort of blockage by either ripped or bent duct I can see with my camera. What is the best way to access the underbelly duct work.

I am totally done with RV repair shops. They are set up only to take money and not actually fix stuff. They would not complete the repair under the warranty. So I need someone help

[myredracer]

Sounds like you need to pull down the underbelly material to see what's going on. Not a fun job and just had to do it on our Spree in a CG after the toilet overflowed during the night.

There are a few screws into some of the trusses going between the frame's I-beams. There are some screws at the front and rear that are installed from above. The coroplast otherwise just sits on the lower flange of the I-beams. You will need to remove some of the foam around pipes and wires that penetrate the coroplast. you need to carefully bend the coroplast downwards in the middle to be able to get it off the I-beams and may need to slide it forward or rearward to get it away from the stab. jacks. May be 2 - 4 pieces. You'll need some Gorilla tape or RV Scrim tape and some gray landscape expanding foam. Be careful not to crease the coroplast anywhere.

Some people have installed cross-pieces using steel or aluminum (right angle cross-section) for added support of the coroplast.

If you do take the coroplast down, you will have a rare opportunity to fix up the poor workmanship in wiring & plumbing and maybe some other things (like insulation?). When I had the coroplast down, I ran a new #6 wire from the A-frame to the converter for an AGM battery in a space behind the shower. Battery in the A-frame is gone. Installing pipe insulation on the PEX lines might be a good idea.

The highly touted "heated underbelly" in TTs is a joke the way it is designed and it's a wonder it works at all. You might consider improvements to it. There are two 2" ducts from our furnace that run into the rear of our underbelly and I doubt there's any heat getting to the FW tank in the front. They install a layer of batt insulation on top of the coroplast which is not a good choice for the location. It also gets squished under the tanks which reduces R-value. If you have the time and inclination, could install rigid foam instead.

Sure not impressed with KZ's heating design on ours. The main 4" duct runs under the floor and air coming out was rather cold. I pulled the duct out and installed an insulated one. The duct to the bedroom was only 2" and I upgraded it to 4". Both mods were a huge improvement. In a previous Spree, they had the main outlet grille under the dinette table and the return air grill inches away. Not very efficient... Our AC ducting was also poorly installed and had to fix it up.

We have had many many workmanship issues in our Spree. Poor quality control for sure. Would not be surprised if your issue is also poor workmanship. Our KZ dealer was hopeless at fixing things. Have you tried contacting the factory? I used to be able to talk to someone there but don't know what they're like now since Thor took over.

[Ralph_Cramden]

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[Bookum32]

Mine is 2x12 rigid board duct.

[campigloo]

You’re getting ready to save some major dollars. Most of this stuff is pretty easy once you get into it. Find an independent parts house. They can be a huge help if you frequent their shop and get to know them a little. You tube is good too.
Getting to the duct work can be pretty easy. Get your screw gun out and it’s all there. If you have to cut it here and there there is a tape made especially for that material. On my trailer, the duct is nothing more than 4” dryer hose. Easy.
Good luck!

[donn0128]

For around 20 dollars you can buy a long inspection camera that connects to a smart phone via USB. Use it to look down the pipes to find the blockage.

[Dick_B]

I have one of those devices where the camera is on the end of a flexible cable and the image can be seen on the hand held monitor. That might be helpful in analyzing the problem.

[Old-Biscuit]

To fully access furnace ducts you will have to remove the underbelly covering.
If you know which section of duct is damaged you can minimize where you have to open bottom section.

[TurnThePage]

I have a similar issue. I've figured out a way to totally bypass the floor duct, and install a new one on the side of the cupboard/storage area. In fact, I'm considering sealing all the floor ducts and rerouting. In my case, this would have the added benefit of keeping water lines heated better. I'm tired of all the garbage that ends up in the floor ducts.