I turned on the A/C, and the car blows hot air. I recharged the system and it showed it was full, but the A/C compressor would not engage, or turn on. I disconnected the low pressure switch on the accumulator and it turned on. I reconnected it to the switch and it still wouldn't turn on. I replaced the switch, bought a new can of freon, but to no avail, the compressor still doesn't turn on. Any suggestions? The system is retrofitted to 134A.
Air Conditioning problems
- Thread starter 87lc2/wo2
- Start date
Jumper the two terminals on the plug on the low pressure switch and see if it comes on.
I jumped the 2 terminal female plug with a wire and the compressor works fine, but even with the new low pressure switch the compressor doesn't work when I connect the plug to it. Yes, the compressor works fine when using a jumper wire, but not when connected to the old or new switch. What do you think about the a/c relay?
How many cans did you put in? For me it usually takes 3 cans.
Have you made sure the condensor wasn't clogged with bugs and debris? It needs air to freely flow across it to dissipate heat off the refrigerant gasses.
Also was the engine fan on to draw air across condensor?
On a last note there is also a screw in between the prongs of the switch on the accumulator. When you convert to R-134a you're supposed to turn that little screw CCW as R-134a operates at lower pressures than R-12.
Have you made sure the condensor wasn't clogged with bugs and debris? It needs air to freely flow across it to dissipate heat off the refrigerant gasses.
Also was the engine fan on to draw air across condensor?
On a last note there is also a screw in between the prongs of the switch on the accumulator. When you convert to R-134a you're supposed to turn that little screw CCW as R-134a operates at lower pressures than R-12.
Red Regal T
Senior Member
- Joined
- May 24, 2001
If it's not blowing cold, the freon is not circulating. Did you change out the orifice tube?
X2. or there is not enough freon in it to kick the compressor on
I used one and a half cans. I'll check the screw on accumulator plug. As far as the condenser fins, there's no debris of any sort blocking the airflow. I assumed I had enough freon when I looked at the gauge on the trigger which stated full. How hard would it be to change the orifice tube? I think I'll take it to a A/C shop.
Additional information: I just got the Turbo T running after 2 years. I gave it a oil change and a bath. While running the engine, I turned on the A/C was not blowing cold and the compressor not turning on.
Additional information: I just got the Turbo T running after 2 years. I gave it a oil change and a bath. While running the engine, I turned on the A/C was not blowing cold and the compressor not turning on.
If it was completly empty 1.5 cans won't cut it. The factory charge was 3.25 LBS of R12 or about 4.3 12 oz cans. And in my experience it takes almost that much R134a to get the system to cool.
You should always charge by the gauge not by how much. Even I could learn to read a set of manifold gauges. Borrow a set of gauges and get a reading and you can get a better picture of what's going on.
Also don't overlook the heater blend door. If it's not closing completely you'll get air from the heater core
Here's a site that contains a wealth of auto AC information. The forums are quite helpful.
Automotive AC Information Forum - ACKITS.COM
Automotive AC Information Forum - ACKITS.COM
You did pull a vacuum on the system before you charged it, right?
Jump the compressor out and let it run as you charge GAS only.... no liquid and watch the suction pressure on your gages, you don't want to freeze the coil. Putting the can in a bucket of warm water will help you get the last few ounces into the system.
Jump the compressor out and let it run as you charge GAS only.... no liquid and watch the suction pressure on your gages, you don't want to freeze the coil. Putting the can in a bucket of warm water will help you get the last few ounces into the system.
