Originally Posted by Rey&Reina
Part of what I did today while giving the unit some time to cool down was to get some foil tape and I taped up the divider and also streamlined the path of air into the ducts. I was hoping the divider was the problem but after I finished taping it up, I still wasn't getting a huge difference in temps.
I will try removing that part from the coils and see if that works.
What I find promising is that it I do get some cold air.
I have a Thor Vegas 24.1. From reading this forum and talking to friends that have motorhomes (Tiffin and Renegade), nearly everyone has problems cooling their coach in full sun on hot days, especially 90 degrees plus.
There are some changes that each provide incremental improvement:
--For lowering heat after driving, I added heavy rubber backed carpet mat in cab area and added insulation everywhere I could access. That includes way up under the dash, under the writing desk area, and especially under the "dog house". All of this lowers the effect of engine heat and engine/road noise. Lots of postings on this subject.
--Bought exterior Sun Shades for windshield and side cab windows.
--Slightly relocated the divider between air intake and outlets to fit properly and taped seams with foil tape.
--As one poster noted, in the Vegas/Axis the styrofoam air channels or "ducts" continue beyond the front ceiling vents to who knows where. I blocked that continuation with self stick insulation. This was an easy and very worthwhile change.
--I let the coach cool down more than normal in the morning to help some in the afternoon. I also run the coach A/C and generator when driving on hot days.
--Buy a small oscillating fan to help circulate air.
--There has been major discussion on moving the thermistor and or letting it hang in the intake air. If your compressor is cycling frequently while your thermostat is still "calling" for cold, it may be the fix that will help. In my case, it had no effect, but it's worth a try, easily reversible and quick.
I just checked my intake/vent temperature differential with a laser gun and it was about 25-27 degrees. This was on an 80 degree morning with the coach under cover. I have never had less than 20 even when the roof is in full sun. If you're getting much less than 18-20, it's worth having a tech check it out. The 9 degrees you noted is way out of spec.
In my opinion, the root causes of inadequate cooling are far too little roof and wall insulation and a lot of single pane glass. All of the changes/additions above will have some effect, but the "fix" for some climates, and those seeking perfection, is adding a second A/C unit. I'm not yet dissatisfied enough to go that route.