Chassis A/C how much freon ?

[jeepfreak]

I've noticed that you have not checked the temp difference between the inside return air at the inlet while on max and the outlet air at the vents. It's all relative. Anywhere around 15 degrees colder would be normal. My gasser on a WH chassis takes 2lbs even.

[tompen]

Post #23. 65* output at 90* ambient (inlet). I understand the temperature differential. My problem was that my other vehicles are colder at the same ambient temperature. The 2 lbs. R134a seems right. Thanks.

[jeepfreak]

Ambient in the trade means outside temp. If you had the temp measured at the inlet inside the coach and it was 90, your a/c is working great. That's a 25 degree td.

[rrussell14]

I clamped off my heater hose also turned on a/c and still not blowing cold both high and low pressure good low side hose sweating and cold condensation pouring out drain ???Fixed this vac line and prob. fixed ??Please excuse my ignorance I dont even know what to call the thing that vac. line was attached to but dont think it related to heater coil.Im no where near my RV at the moment but will post pick when able.

["007"]

Just for added information on coach's with the Evans heater control unit.
It seems that some have been installed incorrectly and they fail because of this.
This thread will also bring to light a problem with the high pressure limit switch and maybe the incorrect one installed by the chassis mfg.

[sc3283]

tom, comparing your coach to other vehicles is not a valid comparison. Evap size, condenser performance, compressor performance all come into play when trying to compare.

Sure your coach isnt as good as the other vehicles....but all that is telling you is your coach doesn't have as good of an AC system

For a true comparison, you must compare your coach to another coach identical to yours that is known to be functioning properly.

All AC systems perform differently from different manufacturers....sure they all SHOULD(in theory) cool great and make ice cubes...but they don't

[tompen]

Thanks everyone. I guess I am convinced it is working as good as it is going too. I am disappointed it wasn't engineered better.
Tom

[dsitterley]

I found this very helpful and other may also..:

Evans Tempcon, Inc

[dmorris189]

The GM platform uses a blend door. Pressures look normal but vents are not cold enough. If blend door for ac is not closing 100%. The heat will win everytime. I would bypass the heater core as a test and i will bet the temps out vents get right in line.