Dash A/C not working...advice, please ?

[Noel]

This is a 2003 motorhome on a W22 chassis/8.1L engine. Dash A/C is an Evans Tempcon RV218552, R134a. (Evans phone and email worthless).

No cold air comes out when activated. It makes a buzzing sound for 3 seconds..and silence for 5 seconds. Another 3 seconds of buzz and 5 seconds of silence. This goes on forever.

Heater works OK, with same noise/silence cycles.

Any ideas as to what is wrong ?

[Noel]

Back from service. Low R134a was the problem. Probably the compressor seal dried out because I had not turned on A/C in 6+ months. Lesson learned. Will keep an eye out to see if the seal has been damaged.

[Noel]

Thank you all for your replies. When I go to a service center, I will have made lots of notes and possible solutions.

THANK YOU...

[1995brave]

Noel wrote:
Had a friend go under coach when running A/C. He saw belt/pulley jump a bit when the buzzing cycled. Noise is under coach, in back of two thermostatically controlled fans...only one was running. Ambient air was 50 deg and incoming dash air was 46 deg. Felt both A/C hoses and one was not colder than the other.

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Looks like you may have three problems.
1. Cooling fan for radiator bad.
2. Belt too loose or compressor clutch going bad.
3. low on Freon.

[marcsbigfoot20b]

Is there a belt on the AC compressor and is it tight?
Is the AC compressor clutch engaging and spinning?

There are so many things it could be.
Low on refrigerant
Low pressure cycle switch problem
Clutch bad/compressor bad
No power to clutch
Bad AC control
ETC

If the clutch does engage for a few seconds then shut off, over and over, then most likely you are low on refrigerant.

[Noel]

Had a friend go under coach when running A/C. He saw belt/pulley jump a bit when the buzzing cycled. Noise is under coach, in back of two thermostatically controlled fans...only one was running. Ambient air was 50 deg and incoming dash air was 46 deg. Felt both A/C hoses and one was not colder than the other.

Was this helpful...?

[1995brave]

Is the noise coming from under the hood or the dash? If it is making noise while the heat is on it sounds like a blower motor problem.

[garyemunson]

I have the service manual. Much longer (76 pages). But need your email to get it to you.

[Noel]

Hi garyemunson.......think I have one. 12 page Owners Manual, RV011454, Rev 7-97.

[garyemunson]

Send me a PM and I'll send you an Evans manual. Sure it's not a Denso?

[midnightsadie]

yep ,ac units most the time need a ac service guy. some times a recharge will get you cold air.

[SidecarFlip]

Open the windows and enjoy fresh air.

[K_Charles]

As said above, anyone that fixes AC units can tell you what is wrong. It sounds like the clutch is going on and off maybe from a low charge.

[Mandalay_Parr]

I would take it to an AC
Guy for evaluation.
Does the clutch engage?
Does the compressor turn?