air conditioner compressor

Low pressure is between the expansion device and the suction hose connection at the compressor. Look on or near the accumulator. Near where you are adding freon.

black cap with a "L" on it

No, not necessary.

The purpose of the low pressure switch is to keep from burning up the compressor due to lack of lubrication. You really sure you want to defeat this? Also; after multiple leaks, are you giving any thought to evacuating the system, i.e., a deep vacuum to remove moisture or how much oil is in the system?

Your lack of understanding WRT proper service procedures is apt to create numerous problems/failures.

Not really, but go ahead.

Refrigerant containing "dye" is for lamers. It causes more problems than it solves, including hose and seal deterioration, gumming up of Schraeder valves, plugged expansion valves and on and on. Don't use "dye" refrigerant. Poop Boys sells and promotes that crap, I believe, so they can sell more compressor swap jobs out in the shop. The only way to do a good leak test is with a proper halide detector. Small leaks may need application of dry nitrogen to boost system pressure to find them.

First, you don't say what car/system this is, so I'll assume it to be a Chrysler H-block layout. If so, the low cutout switch is on the H-block itself, a rubber 2 conductor plug...NOT the evaporator thermostat, which is downstream on the suction side.

First, you obviously have a leaking system, and you're probably already short of oil. Second, since the compressor's already cycling due to vacuum on the suction side, there's a better than 50/50 chance the system is contaminated with air and moisture, which is death to any refrigeration system.

Take the car to a licensed tech and do it right the first time. I've seen dozens of compressor failures/contaminated systems from people getting those infernal "cans" at Poop Boys or similar and a cheapie charging hose. Since 134A doesn't have the same oil miscibility as

12, oil level in the system in crucial to compressor survival. Second in line is owners who add the wrong viscosity oil, or the wrong base stock. Want to see a compressor fly apart? Just put some mineral base stock refrigeration oil in a 134A system! If you do not have a good vacuum pump that'll pull at least 100 torr, you can't do a good job of purging/charging a system anyway.

Don't goof around...take it to a good shop, or your repair bill will get larger as time goes on..

most systems will NOT run the compressor unless there is at least one can of freon in the system- the clutch will not engage. It's a safety feature to protect the compressor- it will usually start running after you put the first can in- it will click on itself.

Cite? Many OEMs install system dye at the factory.

You're confusing dye with sealant and O-ring conditioner.

Actually, R-22 and pressurizing to 75psi or so with Nitrogen works quite well and is 100% acceptable with the EPA.

100 torr? You're kidding right? 100 torr is a little less than 100,000 microns. If my vacuum pump was only capable of 100,000 microns, I'd toss it in the trash! A good vacuum pump is easily capable of

Experience, for one. Back when Du Pont came out with a "leak finding" dye, service bulletins started flying around in the refrigeration industry about these problems. Another big drawback is that is dyes the oil, so you can't do a visual quality check, as well as makes a general mess of the machine inside. There are some cites about this in a couple of auto AC forums, but I'll have to dig them up again.

It's quite possible that newer dyes don't have the problems of the old stuff that was used in halide refrigerants before 134A, but I've never used them, having been warned off years ago.

Yes, it is, and since the 22 molecule is smaller, it makes small leaks for 12 easier to find at lower pressures. A good trick to use for those "half pound a year" cars.

No, I don't proofread! My mistake. Any reasonable AC service pump should get down to

...kicking your ass.

Kill file list:

snipped-for-privacy@hotmail.com snipped-for-privacy@epix.net snipped-for-privacy@hotmail.com

....and a couple of others of which he's probably forgotten the passwords. Most of his other Google troll accounts have already been shut down.