[QUOTE=DaveFL;741415]I posted this on the RV.net group for a larger base for answers:
Replaced compressor, tech said it was the best they could do, "never will cool area, too big" he explained when on max, a/c uses cooled cabin air that is not cooled enough. Best temp at closest vent was 58 degrees on a 90 degree day. Cab was not cool.
Has anybody solved this problem?
Thinking about hanging a curtain behind front seats?
Another option would be reflective window film on side windows. Front already has it above line of vision.
Anything else, don't really want to run genset and house air for travel.
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Seems like from answers I got back running house A/C's while under way is common.
Here are some of the other replies.
1.If you have a heater shutoff valve leaking (Bypassing hot coolant to the heater) you will never get full benefit of your AC.
2.And even the slightest air leak from a doghouse cover will also kill cooling.
3.Also to help the AC you could wrap your AC hoses etc with some pipe insulation.
4.Removed the tube from the thermostat that goes into the evaporator fins. This will let the compressor run all the time but it may ice up on you.
Only when it's really hot out do I put up my windshield screen between the front slide outs to decrease the area cooled.
5.Before I stop for lunch I'll crank the generator (I leave the AC on so it will start when I start the generator) and run it until the dash AC is working well before shutting off.(not good idea, generator should be running smooth and warmed up before adding load)
6.We added a latch to the hall way door to keep it closed and now only cool the front half of the rig. We also added 2-8" diameter 120 volt fans (quieter and move more air than the old
12 volt fans)that we run with the inverter.
7.If you go the curtain route, you can get a number of different curtain traks styles at
Curtain-Tracks.com
8. Add insulation under floor.
I can add things I have done.
I have already added insulation between dash and firewall, rerouted vent tubes, bypassed heat to a/c.
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I am still looking for site with side window sunshades, did see a nice mesh rollup for a car window, white outside and black inside, but it was only 14 inches wide and I need 24 wide and about 30 long. Anybody here have any improvements not mentioned?
For what its worth, virtually all the coaches used to have a curtain track and curtain behind the driver/passenger seats. It is by far the most efficent way to help the dash air (and yourselves). Virtually all the dash ac packages were actually designed/sized for a pickup truck cab, and as such they can't handle an entire RV. The curtain lets it think its a pickup!

A couple of dash mounted fans blowing on the captain and first mate will also help them feel cooler.

Incidentially, 58 degrees at the vent does however seem higher that most properly functioning systems.
Good luck!