Thread: A/C Not Working

Originally Posted by Ralph1Malph

Thanks! Just as a matter of interest, is it 'easy' to replace a compressor?
I know it won't be, but I do have one lying around and would be great if I could do it on a weekend!
I have read that the displacement valve can be replaced as well. I better look into it!

"Easy" is relative.

• Remove gas
• Disconnect and plug pipework
• Remove compressor
• Fit new compressor
• Reconnect pipework
• Vacuum system to remove moisture
• Pressure/Leak test system
• Vacuum system to remove pressure testing gas
• Replace Gas

Because it's a continuously running compressor (even at minimum displacement) you don't want it running with no refrigerant as it'll just pump the oil out. So it all really needs to be done from end to end without starting the car.

If you know someone with a recovery machine, gauge set, vacuum pump, high pressure nitrogen bottle/reg and ideally a vacstat then it's doable.

Not to mention it’s a ***** to get to and remove and install. Even with the body off it’s buried in there.

Originally Posted by DiscoJeffster

Not to mention it’s a ***** to get to and remove and install. Even with the body off it’s buried in there.

Now we're talking!
That's the bit I'm after.

Originally Posted by BradC

"Easy" is relative.

• Remove gas
• Disconnect and plug pipework
• Remove compressor
• Fit new compressor
• Reconnect pipework
• Vacuum system to remove moisture
• Pressure/Leak test system
• Vacuum system to remove pressure testing gas
• Replace Gas

Because it's a continuously running compressor (even at minimum displacement) you don't want it running with no refrigerant as it'll just pump the oil out. So it all really needs to be done from end to end without starting the car.

If you know someone with a recovery machine, gauge set, vacuum pump, high pressure nitrogen bottle/reg and ideally a vacstat then it's doable.

And replace drier,if there is one.

Originally Posted by Ralph1Malph

Now we're talking!
That's the bit I'm after.

When doing the coolant change in a pit with all underbody engine covers off recently I noticed great access up to the alternator from underneath. Potentially a better way to get at the AC pump.

Originally Posted by DiscoJeffster

I don’t need you to check for me lol. There are only two wires that go to it which go the the displacement valve. FYI it’s a Sanden PXE16 compressor. Go and take a look for yourself.

Yeah I checked earlier, we must have different builds or compressors. Mine definately has a clutch and a variable displacement solenoid.
MY11 SDV6 over here

My TDV6 2010 H4 HSE with rear air con also stopped working. It does have a clutch on the front. Its a hybrid compressor with clutch AND variable stroke, with the control valve at the rear of the compressor.
The compressor was spinning with air con on, but no cold air. Pressure test & no gas has leaked.
Service manual states clutch is safety measure if compressor seizes.
There is a service bulletin LTB00693NAS1 regarding this.
I had my system de-gassed, valve replaced with new (disassembled old valve & ill post picks soonish), refrigerant oil replaced (to reduce re-contamination) leak tested & re-gassed. So far so good, but was $900 later.

Well, I finally got around to having this fixed.

Luckily for my wallet is wasn't the compressor.
It turns out the rear evaporator was leaking.
To replace the rear evaporator is expensive and time consuming so I decided have a custom pipe built that bypasses the rear evap.
Seeing as I have removed seats 6&7 and fitted a false floor and fridge slide, I reckon it'll be ok and seems to be a common compromise.
Interestingly, the Indy that did the work, said that it's becoming more and more common for the evaps in older high km D3 to leak.
This is consistent with other brands I've owned and research I've done. The chemical composition of the refrigerant and lubricants simply makes the thin walled evaporators porous over time.

Cheers
Ralph