92 Buick Regal Air Conditioner Broken

[brainboy]

I have a 92 Buick Regal and the air conditioner doesn't work. When I turn on the a/c, it just blows hot air out. There's a sticker under the hood that says it has been upgraded to R34a. I bought a refill kit, followed the instructions in my Haynes repair manual, but it didn't work. It's like the a/c line wouldn't take any of the refill kit, and when I was done and frustrated, my a/c didn't work, and I still had a full refill kit.

Does anyone know why an a/c line wouldn't take a refill kit, or how I can fix this?

Thanks.

[GTP Dad]

It is very possible that there is another problem with your AC rather than being low on freon. It sounds like the system is either full already or there is an issue with the compressor. You may need to pull a vacuum on the system in order to get it to take a new charge. Since the recharge kit didn't work I would take it somewhere to get it diagnosed rather than try to repair it yourself.

[HotZ28]

Usually the compressor needs to be running to add refrigerant. In addition, it will not engage if it is low on Freon. You can jump the low side pressure switch electrical connector, to see if the compressor will engage. When it does, you should be able to add refrigerant. You need a set of gages to monitor line pressure on the high & low side while adding Freon. Remove the jumper when you have the correct pressure readings and reconnect it to the switch.

[retrohwam]

Also, refrain from using any refill product that has a "sealer" to stop leaks. Only use straight recommended freon. The sealer will cause costly problems down the road.

[brainboy]

Thanks for the response, I had a feeling it would be a compressor problem. When you say that I need to jump the low side pressure switch electrical connector to see if the compressor will engage, how would I go about doing that? Also, how would I check the pressure in the lines?

Thanks

[HotZ28]

The ‘low side’ pressure switch is usually located on the side of the accumulator (big aluminum can) near the evaporator and firewall. Remove the electrical connector and jump the two female terminals inside the connector with a short piece of wire with the insulation striped back about ½ in on each end. If the compressor turns over, or runs, see if you can add any Freon. If it will take ½ lb (8 oz) pull the jumper wire out and reconnect it to see if the compressor will continue to run without frequent cycling off/on. If you can get it to cool and the compressor running without the jumper, you will be close. If you do not have the right equipment, it would be best to let an AC shop check the line pressure.

[brainboy]

Thank you for your help, I will give it a try and let you know what happens.