Hi Everyone, my air was not blowing cold. I jumped the a/c low cutout switch and the compressor runs and the air blows ice cold. I added a can of R12a and the pressure with the compressor running is now around 40-45 psi but when I take the jumper out and plug the wire into the sensor, the compressor cuts out. Is the low cutout switch the problem? Can it be replaced without losing charge to the system? Is there any harm in running the system in the meantime with the sensor jumped out? Thanks in advance!!
A/C low pressure cut out switch replacement
- Thread starter LIGHTEMUP
- Start date
- Joined
- May 28, 2001
The lo on my system has a Schraeder in it. When the sw is loosened, the Schraeder is closed.
Great, thanks !!!
Try adjusting the cutout pressure.
CLUTCH CYCLING SWITCH Recommendations From A/C Shops and Aftermarket:
Lower the adjustment of the clutch cycling switch to 21 to 22 PSI with R-134a. This is because the pressure temperature relationship of R-12 and R-134a is different. For instance at 25 °F the pressure of R-12 is 24.6 PSI and the pressure of R-134a is 22.1 PSI.
Pressure Temperature Table
If it is adjustable there will be an adjustment screw between the two terminals. One eight turn counterclockwise lowers the cut out pressure approximately 2 PSI and one quarter lowers the cut out pressure approximately 4 PSI.
CLUTCH CYCLING SWITCH Recommendations From A/C Shops and Aftermarket:
Lower the adjustment of the clutch cycling switch to 21 to 22 PSI with R-134a. This is because the pressure temperature relationship of R-12 and R-134a is different. For instance at 25 °F the pressure of R-12 is 24.6 PSI and the pressure of R-134a is 22.1 PSI.
Pressure Temperature Table
If it is adjustable there will be an adjustment screw between the two terminals. One eight turn counterclockwise lowers the cut out pressure approximately 2 PSI and one quarter lowers the cut out pressure approximately 4 PSI.
