AC blows warm air
 

Help
Ever since I bought my 1988 420sel the air conditionor has blown warm air. I took it to a mechanic and he converted the system to the r-134 (new style) it still is not very cold so I took it to another and he said the freon was ok but the head pressure was very high. Also when it runs I rarely see any water under the car. Where is the evaporator drain hose? Could this be part of my problem.
I can hear the compressor engaging. I have been led to believe that the compressor needs to be replaced. I know they are expensive and if that is the problem can anybody point me in the right direction. Any help would be greatly appreciated
Thanks
jonbob
jon_bob1987hd@yahoo.com

RE: AC blows warm air
 

was the expansion valve has been replaced too?

how much was the low and high side pressure.

RE: AC blows warm air
 

Warm air... bummer for the summer time. Question.... as a previous member mention, the expansion valve may need to be replaced. During the conversion to 134 was the drier replaced? Using, 134 the pressures on will be higher on the systems, you will also use more 134 than r12. Did he replace the gaskets on the compresser from black to the green ones? You may not need to replace the compressor. When switching to 134 you are in a whole new world. The car will not be as cool as it would be with r12. I had to jumper out my electric fan, having it stay on so my car can stay cool. With that. make sure your cooling system is working as it should. I also had to replace my orginal thermostat with one that lets the engine run cooler. Normally if I am not mistaken the thermostat opens at around 180. Normal for Benz but not for using 134 in a benz. I purchased a thermostat that opens at around 160 degrees... made a world of difference. Greate for these hot days in South Carolina. I had to revamp my ac system from r12 to 134 so if you need more info drop a line....

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RE: AC blows warm air
 

maybe your blower control air adjuster doesnt work.. [:o]

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