Community Forums

ChiefBob · 01-12-2022, 06:58 PM

We have recently bought a 2018 Thor Aria 3401, our first adventure in a motorhome after 30+ years in a fifth wheel. We did some tailgating before the weather turned chilly and the roof AC's could not keep up with the midday heat. My fifth wheels had ducted roof AC and the flow from the ceiling vents was significant on high fan speed. The MH discharges on the two roof units are not very far from unit themselves but you can barely feel the air flowing. The return filters are clean. I have looked on several forums and saw references to "low flow" but never the posts they appear to to refer to.

I guess I need to pull the covers off the units on the roof (again) and try to trace the air flow. The roof unit is not accessible at all from the bottom. The ceiling just has 4 round vents and 4 round returns. It appears the ducts are just channels in the blocks of foam between the roof and ceiling. I'd add pictures but my rig is cooling its heals at Freightliner waiting to be looked at for 3 recalls.

Any insight or suggestions are appreciated as I get ready for the coming Texas heat.

chuckftboy · 01-12-2022, 07:31 PM

Yes, pull the covers and check to see if the evaporator coils are clean and that the blower wheels are clean. The PO my have neglected the filters and it doesn't take much for them to pass dirt. Any dust that gets through the filter ends up on the coils and fan blades.

Bangorbob · 01-12-2022, 07:45 PM

Also when you pull the covers, there should be a foam strip that kinda seals the cover with the frame of the a/c. If that is not there your a/c won't work very well. Just a shot in the dark. You can ask how I know this, but I'm sure you've already figured it out.

Martind4 · 01-13-2022, 08:11 AM

My sister had a 2018 Thor Synergy and some of the AC vents weren't hooked up at the factory. Took a year and many different techs before someone discovered the problem. It had even been back to the factory for warranty service and they didn't catch it.

jacwjames · 01-14-2022, 06:26 PM

You might consider buying a small remote camera to check to see the condition of each vent.

I was getting ready to replace my AC's and while I had access I bought a camera and checked my ducts. I actually found two pieces of duct that were not properly sealed at the factory, they didn't tape them when the were installed. Had to get creative to fix, I decided to just add another duct in that location so I could tape the joint from the inside. Found some other problems but was able to fix all the problems.

ChiefBob · 01-14-2022, 07:16 PM

Thanks for the suggestions. I ordered a remote camera so I hope that helps as well pulling the covers. I'm in the middle of converting the washer/dryer closet to a storage cabinet right now.