A/c question

[Smoky1978]

So I just tried to recharge my ac. The clutch will come on but as soon as it does pressure drops than climbs back up kicks on then drops clutch stops engaging.


Anyone have any ideas what it could be?
Thanks in advanced

 

[masospaghetti]

How much refrigerant did you add? This behavior is expected during charging and/or you are low on refrigerant.

 

[Smoky1978]

When the clutch is not engaged it is a good pressure only when the clutch engages the pressure drops than it will climb back up once it reaches good pressure the clutch will engage again

 

[Big Z]

You're likely just undercharged. System takes 22oz refrigerant. When the compressor engages, it will drop the pressure on the low side as it suctions the vapor. You probably don't have enough refrigerant to keep the low pressure switch closed after a few seconds of the compressor working (compressor engages, drops pressure, low pressure switch opens and shuts compressor off to prevent damage).