Originally Posted by hirdo
We have a 2017 Xlite 28sgs. It only has 2 air conditioning vents in the main room that has opposing slide outs. That just doesn't seem like enough for such a large area and really has a tough time cooling when it is really hot. Anyone have any suggestions of how to add additional vents? Or other suggestions or opinions? We have a 15btu unit.
Have you inspected, and retaped, all your air conditioning ductwork? If not it's definitely worth checking out. Pop off the grills on all your air ducts, not just the two in the living room. Inspect the foil tape and make sure there are no gaps allowing cold air to blow into the attic. Next, remove the ceiling grill on the air conditioner and inspect the foil tape on the duct work. Tape over all the air gaps you find. Finally, if you have a ceiling vent that is pre-wired for a second air conditioner (maybe in the bedroom), remove the beauty ring and look for foil tape. If found, remove it and verify that the foam ductwork behind it is sealed by foil tape to prevent cold air blowing into your attic space. I'll post a couple pictures to show you the kind of gap mine had. Half my cold air was blowing into the attic.
One picture shows a smoothly taped hole at the vent pre-wired for AC. I peeled that off and look at how cold air blows out of the duct and into the attic.
One round one shows the hole in the foam air duct and the hole in the ceiling luan. You need to tape the gap completely closed. See the other two round pics.
I had horrible factory taping (read: huge holes) on both sides of the air conditioner plenum, and huge holes on both sides of our vent in the bedroom. The four ceiling vents did not have holes, but the oem foil tape was just gobbed on. I peeled all of that off and retaped all 4.
We get noticeably more cold air blowing into the RV. A big roll of aluminum foil tape at the hardware store was $10. Ask for the HVAC tape.