A/C Recharging Issues
 

I've seen a lot written about the coolant on this board, but not much documented about the recharging process. I am trying to recharge my '83 with Duracool but it does not seem like I am getting any coolant into the system? I've spoke to the guys at Duracool and have not gotten anywhere. The can and hose are working but it appears I am not getting any past the low pressure side Schroeder (sp?) valve. Is there a secret? I've tried about everything and still no trace of coolant in the drier view window and little change in outlet temps?

ANY IDEAS??

Without a refrigeration harness one is really "flying blind" trying to troubleshoot; speaking of blind I hope everyone is wearing safety goggles while they are doing these A/C recharging tasks. Liquid freon (or LPG or whatever is in Duracool) in the eye can destroy it. Your problem could be your charging fitting is not depressing the Schraeder valve stem or the Schraeder valve is bad. I've had a bad Schraeder valve cause such problems. There are tools that allow one to change out a Schraeder valve while keeping the system under pressure (they work like a miniature airlock system). A good A/C shop will likely have such a tool. Cheers, Jim

If you still have the original york compressor, they have stem valves and not shraeder valves. You need to connect the line to the low side and open the stem valve inorder to gain acces to the system to recharge.

The stem valves has a tin cover that unscrew. You will need a refrigerant ratchet to open the valve or a good pair of pliers.

count how many turns it take to back out the stem valve and retighten the valve by half that amount. You want the valve to be in the middle. If you open the valve all the way you will be closing off the compressor.

Remember to close the valve once you have recharge the system before removing the hose.

If you don't know what you are doing take it to a pro. Like Jim said above you can hurt yourself or someone else if you don't know what you are doing.

I tried turning the stem valve with no luck - thiking that may be what was blocking the entry of coolant. I will give that a try!

You really need a refrigerant ratchet in order to turn the stem valve without rounding the stub.

Don't turn the valve unless you have the hose from you refrigerant hook up. Turning the valve without the hose connected will allow any refrigerant in the system to vent into the atmosphere and that my friend is a BIG NO NO.

viewer windows
 

If the AC is putting out any cooling at all and you do not see bubbles in the viewer window the system is full. Do add additional coolant. You may have an overcharged system. Adding refrigerant to a system without the proper gauges is just asking for a big repair bill. All the above posts about the stems are correct. The best to use is a post ratchet. If not use a small cresent so you can keep it tight. I would never use pliers.

Vance, is the AC running, while you're tying to fill? The low pressure side will be lowest when running. Otherwise the can pressure has to overcome the static pressure.

My system wouldn't take a charge, and it turned out that the receiver/dryer was completely plugged.

The valve on the compressor is left handed. Clockwise to loosen, 1 turn should be enough.

If the float ball in the reciever is floating you don't need any more refrigerant, if it isn't you may need to add some.