AC stopped working after changing water pump

Hi all!

I have a '95 4.3 Vortec engine. Yesterday my husband changed the water pump, radiator hoses, and flushed the radiator. He also added freon after checking and seeing that it was a bit low.  Today the ac is blowing hot air.  He says the clutch is not turning.  Could any of this be related?  Before yesterday, the ac worked fine but wasn't blowing as really cold.

I will appreciate any help you can give us.  We live in Louisiana and I can't stand the heat!  :) 

Please have some patience.  No need to post more than once.

Have you tried supplying power/ground to the clutch to engage it as a trouble shooting step?  Have you checked the fuses and relays?  You can swap the A/C relay with another relay like it.  The A/C relay is the 3rd relay from the passenger side, mounted to the firewall.  You should be able to unplug the harness from that relay and any one of the other relays mounted to the firewall and see if that makes a difference.  The one all the way to the passenger side is the CHMSL (center high mount stop lamp) relay.  The next is the high speed blower fan relay.  Then the A/C relay.  And I forget what the other is, but I think it is the manifold tuning valve relay...

Thanks for your response.  I apologize for the double post but I realized that I had posted it in the wrong place and couldn't figure out how to move it.

We'll try the relay tomorrow and I hope that helps.  Again thanks again for the help and the information.

I would guess that it could be your service port leaking.  How was the freon toped off? Did he use a gauge set or one of those cans with the gauge on it?

I had the same thing happen when changing my water pump (among other things) because I disconnected some a/c connectors to make some room. Check all of the connectors going to the A/C system by jiggling them real good, seating/reseating them a few times. It may also help to spray some silicone dielectric grease in them or taking a pencil file to the pins. If this engages the compressor like it did on mine, you found the problem. I'm guessing it's either the one right on the front of the compressor or the one on the dryer (silver canister) facing the drivers seat. Good luck.

Make sure the connector on the top of the compressor is fully seated. That's one of those sensors that one may pull off to get out of the way when trying to do work on the front of the engine so that you don't do any damage to the wires.