General AC Question

[Rwork]

I realized that I'm losing a lot of conditioned air through the heater return vents that are built into the steps in my Montana Legacy 3781RL. I was working on the ATS and realized that a lot of cold air escapes into the belly of the trailer and then over the wall into the basement. If you have the basement doors open then you are losing a LOT of cold air. What are you all using to stop up/plug the vents during the hot time of the year? Send pictures. I placed strips of foam rubber in each slot for now to see how this will work. One of you have come up with a clever soultion I'm sure. Thanks everyone, this is the best most helpful group of people!

[jsb5717]

I never noticed that I was losing cold air out of the basement and storage doors. However, the fix I made for the furnace return air solves that problem as well. I opened up the basement wall and sealed every opening I could find into the living area and into the underbelly. I used rigid insulation and spray foam and plugged it all...except the returns under the stairs. I also wedged and taped rigid insulation above the basement wall, between the upper floor joists. That way the only air that the furnace can breath must come from the coach. It also stopped the summer hot air from belching into the coach from under the rig and through the return vents.

The above stopped the movement of unwanted air and makes the furnace more efficient. It should also stop the issue of cold air moving out of the coach through the return vents.

[AZ Traveler]

If you keep your basement doors closed the compartment will cool off and not cause a lot of a/c loss. The real secret is not camping where it gets really hot.

[Daryles]

Magnetic register covers for the floor (Walmart).
1/8" press board covered in self stick sheets for the stair vents.
Go around under your rig and cover all the holes in the frame with gorilla tape. Clean the area first with alcohol so it sticks really good.
This will also help keep out drafts in the winter.
Remove your ceiling air returns. Look for gaps where they did NOT tape it off properly.
On my aft return, there was a gap I could put my finger through. On the forward return there was gaps on both sides I could put 3 fingers through. This sucks outside attic air into your rig.
Also trim back the opening to match the plastic frame inside egde. Mine over hung about an inch in some places. This allows more air return.

[Matrap27]

Go to the link below and see the vents that my son in law makes that open and close.

https://www.facebook.com/TrimmedOutWoodworking

[Ram Montana High Country]

In my 373RD, I pulled the air return grills and put 1" foam board insulation behind them - will be addressing floor vents soon and finishing ceiling AC vents soon. I'll also be doing the ceiling in the basement adding insulation.

[dieselguy]

I've linked my old post about insulating the pass thru storage several times, but I'll do it again here. My unit is older, but the design of a dropped frame Montana hasn't changed all that much over the years except for more "bling" to distract you from build quality issues.

https://www.montanaowners.com/forums...ht=Design+Flaw