bbgun83

Hello all,
Can you properly re-charge the AC system after a compressor/dryer replacement if the AC clutch is not engaging?

bbgun83

Reason I ask is I replaced my compressor & dryer this weekend after my compressor pulley bearings went out. I took it to the shop today so they could do a vacuum check and recharge. I got a call later in the afternoon saying vacuum was good so they went ahead and added the freon but they told me the clutch was not engaging. They said it would be $60 just to troubleshoot the issue so I told them not to worry about it. It ended up just being the fuse so Im glad I didnt have them look at it. After thinking about what they said and a little research Im pretty sure you need the clutch to engage in order to properly charge the system but I was hoping someone could confirm that for me? I want to call the shop back in the morning and tell them they need to look at it again since the clutch wasnt working but I want to make sure I know what Im talking about. Thanks in advance.
Bbgun

Mod (Ret.)

Was the dryer replaced as well? Anytime you "open" the A/C system, its a good idea to replace the dryer.

techrep

iTrader: (1)

I believe the clutch will not engage until there is the proper charge in the system...

Mod (Ret.)

This is true; it prevents the clutch from wear when there is no pressure detected from the pressure switch/sensor.

bbgun83

Since my fuse was blown the clutch never engaged, I dont see how you can be sure you have the right pressure in your system if the clutch does not engage.

Mod (Ret.)

An A/C shop will connect gauges to the low and high valves to read the pressure. If it's low, you have a leak. Once the leak has been corrected, the system has a vacuum applied to it, and Freon is added. It will take Freon; as the A/C clutch will cycle on/off rapidly until enough pressure is in the system for it to operate correctly.

Pearlman

Yes, it is technically possible. You can warm a refrigerant cylinder and weigh in the amount required, without the clutch engaging, although from your story I would seriously doubt this shop did that. Ask them.

bbgun83

I talked with the shop and apparently they have a machine that just charges the system by weight so there is not need for the clutch to engage. I'm going to take it back in and have them check the pressures just for an insanity check. Thanks all for the help.

techrep

iTrader: (1)

yep...