AC Trouble Shooting, 2005 Suburban LT

[swathdiver]

I had a 2004 Pontiac where the compressor was simply wore out.

 

[OR VietVet]

How long should i leave it holding vacuum to think there is no leak? I kept a vacuum on for 2 hours..and now the system is sealed and under vacuum... waiting to see if it leaks

2 hours sounds good and then turn off for 15 minutes.

 

[OR VietVet]

I had a 2004 Pontiac where the compressor was simply wore out.

It could be leaking at the compressor or just worn out.

 

[swathdiver]

It could be leaking at the compressor or just worn out.

The seals inside were out, wouldn't compress anymore. The old girl got sent to the scrapper, still running, for the price of her cat.

 

[nonickatall]

I verified my compressor clutch engaged.
I'm putting a vacuum on the system.. if it doesn't hold vacuum what is the method used to find the leak? I see lots of ways to find the leak with systems with refrigerant...but not empty ones

So first of all, if the system was open, you should pull the vacuum long enough and let it stand. Because the vacuum ensures that any moisture present in the system evaporates and is sucked out of the system by the vacuum compressor.

That's why I don't think it makes sense to replace the dryer cartridge every time. Because the dryer cartridge dries and releases its bound moisture again. The dryer cartridge is only there to bind any residual moisture that may be present in the system. Because the problem is that otherwise ice crystals can form on the expansion valve and impede the function of the system.

I draw a vacuum for at least 60 minutes on systems that were open.

Then you should leave the vacuum long enough, i.e. without the vacuum pump continuing to run, so that you can check whether the system is tight. Normally you pull a vacuum of -0.1 bar and wait another 40 minutes or more.

If you get the vacuum drawn at all in the first step and the vacuum pump doesn't start to steam, because it constantly draws ambient air into the system and removes the water through the negative pressure and the system maintains the vacuum, that's a good step.

If the system is leaking grossly, you can usually hear it hissing, if the system is only slightly leaking, it may just not hold the vacuum.

If it just doesn't hold the vacuum, I would fill in air-conditioning medium with contrast medium, although this is forbidden in Germany, let the system run briefly, evacuate the system again and then illuminate it with a UV lamp to see where the contrast medium escaped .

It often escapes from the filling valves, which are not properly screwed on, or from the air conditioning condenser, which is of course exposed to environmental influences and stone chips. Or sealing of new components failed, like when you swapt the compressor or whatever.

 

[project_x]

I found I had a small leak on my rear ac lines. So I bought a rear block off kit.
Replaced all the o-rings, flushed lines and put in a new drier...

I think I have leak from this connection

Where I thought I would find an orifice tube...but there was only an o-ring... Is there anything else that seals that joint?