Question about 1990 Chevrolet Suburban

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1990 Suburban AC Icing up

The dryer on my Suburban is icing up when I use the defrost. 60 degrees outside. Is this normal or do I have a problem? Just serviced and converted to R134. That mechanic says it's normal. This truck has rear AC. Please advise ... I do not want to freeze up the system and blow my compressor.

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Icing on the acumulator (dryer) is normal. The humid the more ice

Posted on Dec 02, 2008

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This does sound normal to me. When the defroster is switched on, the AC engages to help the defroster be more efficient by acting as a dehumidifier before the warm air hits the windshield.
It is possible that the AC system may be over charged with Freon. But, I must put my faith in the mechanic and that he is honest as many are and has done you well.

Posted on Dec 02, 2008

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