Not have A/C come on with defroster
04-26-2017, 01:42 PM
#1
Melting Slicks
Thread Starter
Not have A/C come on with defroster
Any way to NOT have the A/C come on when using the defroster?
On some cars,there is a "hack" (series of buttons to engage) to prevent the a/c from coming on when using the def.
Tks
\db2
On some cars,there is a "hack" (series of buttons to engage) to prevent the a/c from coming on when using the def.
Tks
\db2
04-26-2017, 02:51 PM
#3
If the outside air temperature is warm enough the compressor is going to run to reduce moisture in the air stream and prevent extreme windshield fogging while either the defog or defrost modes are selected. For this same reason you cannot engage recirculate in the defog or defrost modes, doing so in heat mode is allowed but can rapidly fog the windshield and windows unless humidity levels are very low.
Defog and Defrost modes vary only in how much of the total airflow is directed to the windshield and windows; defog sends some airflow to the floor directed outlets. If the outside air temperature is near or below freezing the compressor will not be engaged regardless of mode selection and usually under these conditions the moisture level is low enough to prevent fogging of the inside surfaces.
The compressor won't turn on if the temperature outside is low enough to cause damage and the current environmentally friendly refrigerants will operate without damage at lower ambient temperatures than the older freon based systems that had a higher minimum operating temperature to avoid having the gas turn to a non-compressible liquid.
Defog and Defrost modes vary only in how much of the total airflow is directed to the windshield and windows; defog sends some airflow to the floor directed outlets. If the outside air temperature is near or below freezing the compressor will not be engaged regardless of mode selection and usually under these conditions the moisture level is low enough to prevent fogging of the inside surfaces.
The compressor won't turn on if the temperature outside is low enough to cause damage and the current environmentally friendly refrigerants will operate without damage at lower ambient temperatures than the older freon based systems that had a higher minimum operating temperature to avoid having the gas turn to a non-compressible liquid.
