dash a/c problem on '99 Beaver Contessa

[Richard Donelson]

Currently I'm trying to get my dash A/C working properly on my '99 Beaver Contessa. The other day while changing A drive belt I noticed the clutch plate for the A/C compressor appeared out of line. When grabbing hold of the clutch it fell off in my hand. Apparently over time the bolt worked its way out and fell to the ground. Fortunately it didn't come off and go through the fan and radiator.
I cleaned the plate and remounted it. The compressor works and I topped off the 134A. For some reason the evaporator fan (located in the front of the coach) does not come on like it should. I tested the relay and its good. I jumped the relay and the fan runs fine. I'm thinking the pressure switch on the high pressure line might be bad.
Does anyone have any advice, or is there a site where I can obtain a wiring schematic for my Contessa?

[Edward Buker]

The switch may be a trinary type and the on pressure is fairly high at 240lbs or even a bit more. If the charge is low or if the ambient temp is low enough the pressure on the high side may not reach a high enough pressure to trigger the sensor. If you have reached 260lbs on the high side and the sensor still has not been triggerd then I would think that something is wrong.

If your system has always held pressure and no moisture has gotten in causing corrosion, and you have not had a compressor fail allowing debris in the system then usually these sensors are pretty reliable. I have charged my R134 systems with a switch in place to bypass the pressure sensor and have the condensor fans running constantly. If you are charging to a specific pressure at some ambient temperature, you need to have the condensor fans on otherwise the ambient around the condensor is inaccurate and will make it impossible to set the charge properly and you will be under charged.

If you wire the switch in to bypass at the pressure sensor, then that allows you to verify that the wiring and fans are O.K. right up to the sensor. When the charge is correct and the ambient is warm enough, then you can check the sensor function with the bypass switch off. If the fans do not come on by 260psi on the high side then you know that the sensor has to be bad. You can try and tap it while high pressure is present and see if it will engage. If it does I probably would use it as another confirmation that the senor is bad and not trust it. I do not have a schematic but these sensors are usually right by condensor. Hope this helps.

Later Ed  

[Richard Donelson]

Thanks for the info Ed. I will take your advice and let you know the results. It may take a few day for the conditions to be right.
Rich

[Mike.Way]

Just some anecdotal information.  Our '99 Safari, built when Beaver and Safari were symbiotic, had Acme Air Conditioning bits and pieces.  I had to replace some tubes and the condenser on the Safari and the Monaco tech line gave me Acme's number.  Unfortunately I believe they are now out of business. Turns out a lot of the pieces are related to Ford cars; specifically the Taurus which means it was probably up and down the Ford line.  When the compressor failed in the Beaver I was able to get a replacement at the ice cold auto air locally.  Beat the heck out of getting one for $1200 + overnight.

Mike

[Richard Donelson]

Ed,
For everyone interested, I took your advice and replaced the trinary switch on the high pressure A/C line. It was a 4 wire switch that I ordered from Air Parts, Inc., Ocala, Fl, Part # SW4085, and it only cost $20.00 with free shipping. When I turned the A/C on, the clutch engaged, and the evaporator fan came on and cycled properly. The dash air became cool as a cucumber. Thanks for the help.

[Edward Buker]

Richard,

Glad it worked out....sometimes we get lucky.

Later Ed