Chrysler Repair: defroster intermittent function: 2000 T&C, cylinder car, refrigerant pressure

Question
sometimes my defroster will not clear up the windows all windows fog up in cold weather. then I turn the car off and turn it back on and the defroster works. six cylinder car year 2000. last year I had a thermostate put in and it was allright last winter. not sure whats up with this.  

Answer
Hi John,
It probably is the case that the AC compressor is not kicking, which is used to pre-cool the air that is applied to the window. So chances are the refrigerant pressure level is down at the margins where sometimes it kicks in and sometimes not, and needs a recharge. You can check that out by listening for the compressor to be on when you ask for defrost. If it is running and you aren't getting the defrosting effect then it is likely a malfunction of the blend air door that mixes the cool air with heated air in the proper amount.
Roland
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