I'm trying to charge with an A/C Pro DIY kit. My compressor only comes on for a few seconds, making a squeel, while the pressure goes from 15 to 55. The compressor cuts out and the pressure goes back down. This repeats. I think it would go even higher if I put more in, but I don't want to overcharge. The thing is I didn't put that much refrigerant in and I'm getting nothing but hot air. It seems from the directions, the pressure should hold. Can any one diagnose my problem?

 

Where is the squeal coming from? Is the belt slipping on the A/C pulley when the clutch engages?

 

I think the squeal comes between the end of the compressor (name? the part of the compressor I can see spinning off and on) and the pulley. I sprayed it with wd40 and it's not as bad now. From further reading here, I see where it may not have had enough R134a to start with. What I'm worried about is going into the red zone if I put any more in.

No I don't think the belt is slipping, but I'm taking another look.

 

If it's not the belt squealing, it's either the clutch, or the compressor. What ever it is, it needs to be repaired.

There's plenty to worry about when using those kits, they are not accurate and are extremely dangerous. The system must be charged with the correct amount of refrigerant and oil to work properly. As little as 2 ounces either way, and you'll have problems. If it's undercharged, it will not cool properly. If it's overcharged it will not cool properly either, but you'll run the risk of doing permanent damage to the system, and to yourself while charging it.

There's only one way to know how much refrigerant is in the system: Drain it, evacuate it to 29.4" Hg for a minimum of one hour, and recharge it with the proper amount. High and low side pressures, clutch cycle times, and outlet temperatures will vary greatly depending on a variety of factors. There is no set pressure for either the high side, or the low side, and the clutch may or may not cycle. If the refrigerant capacity of the system is 30 ounces, and it is not evacuated before charging, 30 ounces of refrigerant will overcharge the system causing high side pressures to become dangerously high.

To start with, you'll need a manifold gauge set, an evacuator, and an accurate digital scale. Probably looking at $300 to $400 minimum. Laws vary from State to State, and some States allow businesses to rent the equipment, some don't.

 

IMO do yourself a favor and take it to an A/C guy. I did mine with Chuck and other guys on the board last year. By the grace of god and the boys it's still running.


If I had to do it again............sh"t!

 

OK, Captain, I won't try this myself. Spittybays, thanks for the second opinion.

What should a drain and recharge cost if there's no clutch or compressor repair needed?

 

In my neck of the woods, Eastern Long Island, to do that is about 80 bucks with a diagnostic. Check your Private mail I will try to give some cost saving things.
I do not see the year of your truck or your state.