Basement isn’t getting cooled anymore

[Barb]

Hi, 2012 36 rear Living room . So the AC isn’t cooling the basement . It was but it stopped so all that heat is coming up the vents. . Anyone know anything about that? Barbara and Patrick

[travelin' texans]

Originally Posted by Barb

Hi, 2012 36 rear Living room . So the AC isn’t cooling the basement . It was but it stopped so all that heat is coming up the vents. . Anyone know anything about that? Barbara and Patrick

Your basement does not have vents nor any duct work to provide cooling from the A/C to the basement. Not sure how you may have, or thought you were, getting cooling in there but it wasn't from the A/C.
It does have at least 1 small duct from the furnace & the returns are pulled through the basement to aid heating during the winter.
If you're feeling heat from the returns under the steps & under the closet near the door now you can block them for the summer, but be sure before running the furnace to remove whatever you blocked them with.

[Barb]

Thanks Danny and Linda.
We are wondering what part of the Coleman Mach AC Units causes the fan speeds. All summer we haven’t had enough AC to cool the rig. By 4:00 it’s up to 88. We’re in FL so It’s hot. We haven’t had this problem before. I thought it was the basement AC. Barbara

[travelin' texans]

Originally Posted by Barb

Thanks Danny and Linda.
We are wondering what part of the Coleman Mach AC Units causes the fan speeds. All summer we haven’t had enough AC to cool the rig. By 4:00 it’s up to 88. We’re in FL so It’s hot. We haven’t had this problem before. I thought it was the basement AC. Barbara

Should be 3 settings on the "fan" switch "hi, lo, auto" if set to "auto" the fan will only run when the A/C compressor starts, set to "hi" or "lo" the fan will run continuously til you set it differently. Honestly I couldn't ever tell the difference between hi & lo so set it to hi.
FYI that fan switch does not control the furnace fan, it comes on when the furnace fires up, but if that switch set to hi or lo the A/C fan will be blowing also. The A/C only blows from the ceiling as will the heat pump if equipped, the furnace ONLY blows from the floor registers.
In hot areas with both A/Cs running 24/7 we could barely keep it comfortable even with solar shades on all the windows & the awning out. Running a couple fans, 1 inlo bedroom & another on the opposite end of the coach, will help tremendously.
Search this forum for countless mods to A/C system to improve cooling. Sounds like this rv is new to you so not sure if the PO did any of the modifications.

[XCMARK]

Our 2015 RL-38 is a similar to yours, we have no issue with keeping cool on 90*+ days with both AC units running. It stays 72* inside. The first thing to have checked is the AC plenum on the roof, I found a 1" thick foam block that separated the return air and supply air as it comes out of the roof AC unit into the ducts in the ceiling. The cold air was coming out of the supply and right back into the return and never made it into the living space. The second problem is the return air duct is to restrict and can benefit from a third return air vent directly under the roof unit in the center rather than the left and right side of the coach. There is a few pictures of this mod where adding the center grill and filter are shown with good detail. leave your awning out and set as low as possible with your shades down does help with keeping things cooler.