a/c recharge/compressor question

[Jroberts238]

So I went out and bought a recharging kit for my ac but when I hooked it up the guage is reading no pressure and I'm pretty sure my compressor isn't on. I heard somewhere that these compressors have a safety on em that cuts it off if the pressure is to low in the system. Is there any way to reset it so I can charge the system? I may be dealing with a bad compressor but I figured i would try this before I paid that bill.

[trb]

Did you get one of those one hose "kits" that has a refrigerant can on the end, or is it a kit with a separate gauge? I personally prefer to "rent" the actual AC gauge set from Autozone. If you have one or a similar auto parts place close by they will usually rent out the gauges for a deposit you get back when you return it.Anyway, there should be a low pressure switch on the AC lines that does indeed cut off the compressor so it is not ruined if the refrigerant charge gets too low. Luckily I have not had to look for it, but I'm sure somone else knows where it is. You usually just temporarily jump the connection with a piece of wire and it will turn on the compressor clutch. Then you can add the refrigerant to the system until the pressure is above the minimum, then you can reconnect the wiring harness to the low pressure switch.But has the system been low/ not working for a while? If it has a leak, and all the pressure is gone, it may be full of regular air. If that is the case, you will have to fix any leak, vacuum the system down to remove all air and moisture in it,(moisture is BAD for the system) and then recharge it. If you have no pressure with the compressor not running, I'm thinking all the refrigerant may be gone. Usually there is still some static pressure in the system even if the compressor is off.If you do jump the switch, and are successful in charging the system with what you bought, you still might not have it work properly. I hope you are just low and not completely out due to a leak.

[Salsa Guy]

You can start adding some refigerant until the compressor comes on a little at a time. But if you have 0 psi more than likely you have a bad leak and your system will be full of moisture. You need to find the leak, fit it, replace the reciever/drier, evacuate the system and charge again.

[Jroberts238]

I just bought one of the off the shelf recharge kits. And honestly I not too confident in the guage. Had to return the first one and the second one didn't seem to work quite right