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Discussion Starter · #1 ·
So If I jump across the pressure switch connector the a/c clutch will turn and suck freon in and get cold in the car. I used a whole retrofit kit. But when I plug it back in the clutch wont come on. Bad switch right? My question is it I unscrew the pressure switch will I loose all of my freon?
 

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You will not loose freon. there is a schrader valve under the switch. You will hear a hiss of a very small amount of freon as you unscrew it but that is it. Odds are that if you are jumping the switch and it works then the switch is bad.
 

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The pressure switch still won't allow the A/C compressor to stay on if the pressure is too low or too high. So what are your high and low-side pressures with the compressor running?
 

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I just put a retro kit in mine,and I had to replace the switch.You will not lose your freon by removing that switch.It is probably the switch if it runs when you jump across it,so I would just replace it.It is cheap so you will not be out much anyway.
 

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Discussion Starter · #7 ·
actually ya know, funny thing. I was working on it today and my dad is like "hey there is an adjustment screw under the plug". I just adjusted the screw a turn and it works amazing.
 

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do you have any idea what pressure you adjusted the screw to?

Not a good idea if you don't.
 

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Discussion Starter · #9 ·
I turned it one turn counter clock wise and it started working. Can I put a gauge on the low pressure side and find out what it is set at?
 

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Not only CAN you, you SHOULD. Both the high side and the low side. You should have done that before messing with the switch.
 

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Discussion Starter · #11 ·
So it would have been better to replace the switch than to adjust it? Why is it adjustable? What should pressure be at the low side? high side?
 

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For the love of god. Put down the Cap'N'Crunch and Red Bull for a second, would you? PRESSURES. TAKE THEM. Should have done that first before you did ANYthing to the switch. Maybe you got lucky and made the perfect adjustment, but what you're doing now is building a fire in your living room without even looking at the thermostat.

You'll want to be under 250 PSI on the high side reading and higher than 30 psi on the low side reading.
 

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Discussion Starter · #13 · (Edited)
Okay so if its not than replace the switch? There wasnt any pressure in the system when I started. It was completely empty. It was set up for r-12 and I used a retrofit kit, 36oz of freon and oil.
 

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did you repair the leak, replace the shaft seal and o-rings?

What refrigerant did you put in,,,, FREON is a trade name for R12.
 

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Discussion Starter · #15 ·
It was R-134a. Should I take the pressure reading with the compressor running or not?
 

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It was R-134a. Should I take the pressure reading with the compressor running or not?
Did you repair the leak?

Or do you want to do this a few times before, you find it?

Pressures without the compressor running means NOTHING, except that you have something in the system above atmosphere, does not tell you the ALL important quantitiy.
 

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Discussion Starter · #18 ·
I have a gauge for the low side, a ####ty one but a gauge none the less. I got between 28 and 30 psi with the compressor running. And I am not sure it has a leak. I just bought friday, they guy I got it from said he had it worked on, so I am thinking he had it evacuated. When I started working on the a/c I pushed the schrader valve in and I had a wee amount of pressure.
 

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Why would you add refrigerant, if you have no idea what has been done?

Its a critical charge, you cant'd just add refrigerant and hope it works.

It takes 2.2lbs from the factory, it has to be accurate within 1/10th of a pound.
 
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