A/C not cooling enough

[Bob.Squires]

Ok folks. I’m back home now and have my IR thermometer

Not sure if I’m doing this right (tell me if I’m wrong). I told reading at the intake filter and at the closest duct vent. These are my results

Front a/c

Rear (bedroom)
Input: 74.5
Output: 58
Net: 16.5

Front larger living area
Input: 76
Output: 64.2
Net: 11.8

So does this look in range? I’m thinking not.

[Chance]

Doesn’t look right to me. Your rear A/C is in right range, but your front one appears to be the problem.

Once you fix that (or get it fixed), then you can decide if the two A/Cs are large enough for the motorhome. I’d get it working right first before worrying about reducing heat gain.

By the way, is the front A/C larger in rated capacity? Sometimes front is 15,000 and rear one 13,500. That would make your front one even more important (as percent of total).

[Bob.Squires]

Originally Posted by Chance

By the way, is the front A/C larger in rated capacity? Sometimes front is 15,000 and rear one 13,500. That would make your front one even more important (as percent of total).

Pretty sure the specs for this unit is 13,500 for both.

[Chance]

Based on your readings, you could be losing ~ 4,000 BTU/hr of performance, maybe more.

As long as you took readings the same way, and didn’t have RV door wide open in front during test, then it appears front A/C is not performing to spec.

Please let us know what you find.

[DanChateau33SW]

There is no replacement for 15k BTU air conditioners. I used to live in WA state and our first travel trailer had a single unit. We had it upgraded new to a 15k because I had heard plenty of stories of others with 13.5k units and 2 of them that could not keep cool in places like FL and TX. We were camping and it was 107 degrees. Our trailer was sitting at 68 with the single 15k unit. Other MHs and 5ers with multiple units could barely hold 80 degrees. Needless to say, that day sold me on the 15k BTU units.

[JimOIB]

Check the baffle referenced in this video. Mine was pulled forward so cool air was going out the exhaust.

https://m.youtube.com/watch?v=AzdQoDublzs

[Pete'sMH]

Originally Posted by jimbo12

Check the baffle referenced in this video. Mine was pulled forward so cool air was going out the exhaust.

Check this!! I saw this video and checked mine. The baffle was displaced by wiring and was nearly horizontal! Fixed it with metal tape as indicated and the improvement is HUGE. Just short of life changing. I was ready to order a second air conditioner but now am holding off. I may still decide to do it but at this point it’s up in the air. Amazing!

[Bob.Squires]

Taking in all these tips to improve my cooling. I noticed there was s lot of warmth coming from underneath the sink. Upon investigation I found the source of the heat was the hot water heater. So one lesson is to turn on hot water, once hot do showers and dishwashing and then turn it off

When I look close at the water heater I see that most of it is wrapped by a white insulation. I can tomorrow ch the white part and feel very little warmth. But the exposed area around the water connections were very hot. See picture


So I’m wondering if I should get some insulation spray expanding foam and treat the exposed metal part thoughts?

Seems like this area should have been insulated. Anyone else’s like this.

[SuperD]

Bob, sorry I didn’t see this thread earlier. I also have a 29M, purchased and used in the Texas heat. After much investigation I discovered a couple of things related to the cooling. The factory ducts are very restrictive and don’t allow good airflow due to numerous turns and bends, not much you can do about that. I installed a round vent in both AC inside covers, only took about an hour for both, and they have made a huge difference in cooling. The round vent goes directly below the AC exhaust so there is a direct path for the air with much better flow. The flow can be directed where you want it by rotating the vent. Many other 29M owners have done this simple mod with excellent results.



In south Texas I can run just one AC most of the day, unless I’m parked in direct sun. I normally run the back AC during the day and front AC at night to keep the noise separated from us. I know the water heater gets a little warm but not that much, I never shut mine off except when on the road.

The vents are available on Amazon, search for “round RV vent”. Remove the inside cover, use the new vent as a pattern, cut hole with a jigsaw, and mount with four screws. Really is easy to do.

Hope this is helpful to you!

[Bob.Squires]

Originally Posted by Pete'sMH

Check this!! I saw this video and checked mine. The baffle was displaced by wiring and was nearly horizontal! Fixed it with metal tape as indicated and the improvement is HUGE. Just short of life changing. I was ready to order a second air conditioner but now am holding off. I may still decide to do it but at this point it’s up in the air. Amazing!

Thanks for this suggestion. I found that the baffle that separates the intake and outtake allowed for a portion of the output to be sucked right out the exhaust. Not the gap below the wire. Both a/c units were that way. I fixed that with foil tape but it’s been over 100 every day of late, so it’s hard to see much improvement yet.

[Bob.Squires]

Took our little bus to a dealer and they said that a/c was working correctly. I continue to search for sources of heat coming in.

An odd thing that I have noticed is that the bedroom vent closest to the bathroom, shows light. This picture was taken during the day but with all blinds down and lights off


I have checked the roof and there are no holes. Seems like if I can see sunlight, I must be getting heat in. Thoughts???