Optimizing Cooling

[Tyrelvanniekerk]

Hi,

I live in Texas, and a normal day at this time of year is around 92-98 degrees Fahrenheit. I have no problems keeping the RV cool. I have one unit in the bedroom and two that are close to each other, one in the living room and one in the kitchen.

I have noticed that I have to chase the temperature throughout the day. The actual temperature will be around 74 (with an independent sensor), but the kitchen thermostat shows 82, and the living room thermostat shows 77 (Even though they are only 10-12 feet apart). I can imagine how hot the black plastic cover on the A/Cs gets, and I am sure that reduces the unit's performance. I wonder why they don't add more insulation up there by default.

Is it possible that the sensor that sends the temperature to the controls is too close to the roof and shows a mixture of indoor and outdoor temperatures?

How best to regulate the temperatures? I have to increase the set temperature manually during the day. Otherwise, it will keep getting colder and colder to the point of discomfort. I almost wonder if I should set it to a lower temperature, say 76, let it run until it gets there, and leave it there.

I just have not found a good balance. Any suggestions? Also, is it worth running the extraction fan in the kitchen when it's this hot outside? Makes me wonder if it would just be blowing cold air outside.

Thanks,
Tyrel

 

[geotex1]

Insulating the unit would cause more detriment than benefit... However, you can definitely help matters with changing the color of the shroud. I know plenty of folks in the southwest who make this mod. Krylon Fusion or Rustoleum Any Surface is cream/ivory was pretty popular with GDers with the last color scheme...

Anyway, the thermostats never seem to be in good spots - too near radiating heat of windows, in locations of dead air, etc. Personally, I relocated or main A/C thermostat and run the bedroom A/C 2 degrees cooler and than the main and with bedroom unit fan on LO AUTO and seems to be the best balance with the racetrack ducting to keep both units cycling and a pretty consistent temperature throughout.

As an aside, I also taped up the truss openings and perimeter framing in each vent and skylight with HVAC reflective foil tape and added insulation around the inside skylight trims. This made a huge difference in the indoor environment that only got better when I added thermo blinds to the skylights.

 

[jkwilson]

The black plastic isn’t an issue. The big heat source is under the plastic, and black materials radiate heat better than other colors.

 

[trailrydr]

A couple of our best AC performing mods to help insulate against the UV and heat buildup was to: replace all OEM curtains with thermal/blackout curtains; thin shade on door window; insulated skylight cushion; ceiling fan in kitchen area to circulate floor to ceiling air; MaxAir vent shades over roof vents; and slide toppers.

Still have the issue of regulating the bed/kitchen thermoststs to cycle off each other, and the buildup of heat in the ceiling race track during non-AC run times. Found that keeping (the elevated) bed room door closed helps with thermostat cycle issues - since all cold air wants to go down and any heated air wants to rise up.