Need Help to Diagnose Dash AC Problem

[TC_Z]

Our 2007 Winn Voyage dash ac is not working. It was blowing warm air months ago and I charged the system and it seemed to work fine for next trip. But it has gotten warm again. Now when I try to charge the system I hear the clutch going on and off every 5-10 seconds. It didn't do that previously. I assume the pressure switch is cutting off because pressure is too low. I cannot find a freon sight glass on the system. Not sure which mode is clutch on or off, in one mode the pressure is good (on the high end of the green good scale). In the other mode the pressure drops to zero. The gauge jumps back and forth as I hear the clutch clack. I tried to charge the system for 10-15 minutes without the engine running and it wouldn't fill. So I tried filling system with engine running and let compressor cycle on off with can connected to charge for 10-15 minutes no change, no change in either zero or the green good reading. I inspected all the connections, none appear to have oil leak. I called RV service center, they will not provide a cost estimate and must drop off and it will take approx 2 weeks to service. Based on what I've described anyone have a guess what problem could be? I am considering trying the leak dye next. Yet odd that the pressure is good sometimes but zero other... Any help or guidance would be appreciated.

[J-Rooster]

I just had my system recharged a few months ago by my local wrench. He also told me most A/C's in vehicles are hard to get them completely stopped from small leaks due to all the vibrations under the hood.

[turbojimmy]

Not sure what "modes" you're referring to, but if the compressor is cycling it's likely undercharged. The pressure switch that cycles the compressor is on the low-pressure side of the system. BUT - low low-side pressure coupled with high or normal high-side pressure could indicate a problem in the orifice or expansion valve (depending on which is used in your application). You need gauges that read both sides of the system to properly diagnose.

[dakdave]

could be too much air and moisture in system.You need to hook up dual gauge set and read both high and low side pressures.dessicant bag could have come apart and plugging expansion valve or block causing compressor to cycle.

I would take it to any competent ac repair shop and have it checked.Very easy to overcharge system.Usually done by weight.

[Tinstar]

I had a problem with mine that was fully charged. The water line from the radiator runs through the coil and the vacuum was leaking. Replaced the vacuum line so the heater door closes and now I've got cold air again. You can also put a water valve inline and you can close it in the summer and open it in the winter.

[sch911]

Get it to a shop that knows how to fix it. For A/C this would not necessarily be an RV dealer. How about the chassis dealer?

[MountainAir05]

If you don't have a service gauge set , go to autozone. They loan them out. Then post the reading for high and low. Too much freon will also shut the system down.

[Big_Katuna]

Mine in my Fleetwood was intermittent but different symptoms. Mine would blow ice cold for 20 minutes to a few hours then quit blowing cold like you pushed the ac button off. Fan still blew.

It was a bad thermostat.

I called Fleetwood and they emailed me PDF files for the system. It is a Denso. It had a trouble shooting matrix.

My system does not have an inspection window. Your gauges should tell the story on it being empty. Your dryer may be full and you may have non-compressible moisture in the system. You need to find the leak to properly fix it.

And hate to tell you, nobody can give you a firm estimate without troubleshooting it first, which may places don't do free anymore. Most will apply it to the total.