Air Conditioning Compressor - Identification and Proper RCV

Found out yesterday my air condition is not working, at all. No biggie, glad I caught it early before it got really warm.

I have a hunch it's the RCV because there's line pressure on both sides still indicating it still has a charge in the system (unsure of actual pressure, did a quick screwdriver tap on the schrader valve on each line as I don't have a set of manifold gauges).

Have a buddy coming over with VAGCOM later today to see if we can see line pressures, RCV voltage, etc.

I've been all over the forums, but have been sticking with the NMS/B7 forum for the bulk of reading simply because we KNOW the RCV is a common issue. What I can't find is any identification of what compressor the NMS Passat uses (other than it being a Sanden) in order to identify which RCV I'd need to purchase. Nor can I find any pictures identifying where the RCV is located in the compressor on the NMS.

Anyone have any idea on the info I'm looking for? Perhaps I'm being lazy and not getting under the car and looking, but I'm already working under my Corvette tidying some things up and my jacks/stands are being occupied.

don't know if the '12 is the same, but on mine there are 2 possible compressors brands that are interchangeable, but have different RCV. only way to know for sure is get under car and look at compressor data plate and look at the RCV to see the mount. the RCV has 2 wires to it and mounts with a bolt on the base holding it in or a snap ring holding it in a recess.

Blah. Ok, guess I'll be getting under the car. Is the RCV located on radiator side or engine side of the compressor? Or in the back?

This link may help you out even though it's for the A5 Jetta/Golf:

http://www.myturbodiesel.com/wiki/vw-jetta-and-golf-sanden-ac-compressor-control-valve-replacement/

Had VAGCOM on it today. Refrigerant Pressure was holding at 6.0 bar. My buddies 12 Golf R (who came over with the VAGCOM) was at 12.0 BAR and fluctuating. Compressor load on my car was l.ike 1.9 vs 8-10 for his car. I'm thinking RCV given the lack of fluctuation in the line pressure.

Check the output in amps to thecontrol valve.
If it maxes at 0.86 amps and stays there then the valve is not driving the output like it should.

The RCV is on the end of the compressor opposite the pulley. You can clearly see it from underneath the car. It either has a snap ring holding it in or a bolt. All that I have ever seen on the 2012-newer Passats are a snap ring style. EX019 is the part number for that one.

redbarron55 said:

Check the output in amps to thecontrol valve.
If it maxes at 0.86 amps and stays there then the valve is not driving the output like it should.

Click to expand...

Never passed that. Usually around .82

mountain-valleymotors said:

The RCV is on the end of the compressor opposite the pulley. You can clearly see it from underneath the car. It either has a snap ring holding it in or a bolt. All that I have ever seen on the 2012-newer Passats are a snap ring style. EX019 is the part number for that one.

Click to expand...

Thanks for that, big help there.

It it goes up to it's max and stays there then that is what I mean.
If it modulated like it will if it is cooling correctly it will be varying up and down to regulate the cooling.
The amps go up the pressure goes up etc.

Both the amps and the pressure were dead solid, not moving at all.

So.........went to fix and get it working today. Hooked up a recharge hose to bleed the system out and was surprised when it bled out in about 45 seconds or so. Seemed quick to me. Thought to myself "no, couldn't just have been a low charge." Ran and grabbed some refrigerant and put approximately the correct amount of refrigerant in (most likely a little under the requisite 575 grams + or - 5) and sure as anything, blowing ICE cold. No audible leaks so if it truly has a leak it's very small. Going to see how long this charge lasts and if it does deplete, do a charge with a UV leak detector in it.

Anyone need an RCV? I have a brand new one sitting here.

PM sent about the valve.

My Passat AC has been taking longer and longer to turn on (started a few weeks ago where it took five minutes to turn on and today it took an hour).

Once it's turned on it's fine (plenty cold), and never goes out once it's been on - does that sound like an RCV issue?

^^^Yes. Shutting AC off, along with engine, and re-starting will get the valve to work. There's a post here where someone describes his trick for getting the RCV to work. You can buy a bit of time this way, but ultimately, you'll need to replace the valve.

tdiatlast said:

^^^Yes. Shutting AC off, along with engine, and re-starting will get the valve to work. There's a post here where someone describes his trick for getting the RCV to work. You can buy a bit of time this way, but ultimately, you'll need to replace the valve.

Click to expand...

Are you saying that turning the car/AC off and restarting will get the RCV to work in the short term? Because I tried turning the AC on and off several times (with the car running) and that didn't seem to work at all for me.

I've been looking for that post for the past ten minutes and can't seem to find anything.

^^^It works for me. It might require shutting off the engine, as well, waiting a minute or two.
Yes, a royal PIA, especially in the heat, but it has kept me from replacing the valve.

tdiatlast said:

^^^It works for me. It might require shutting off the engine, as well, waiting a minute or two.
Yes, a royal PIA, especially in the heat, but it has kept me from replacing the valve.

Click to expand...

Thanks - I'm certainly dubious that'll work for me, but at this point I'm willing to give anything a shot!

Thanks again for your help!

mountain-valleymotors said:

The RCV is on the end of the compressor opposite the pulley. You can clearly see it from underneath the car. It either has a snap ring holding it in or a bolt. All that I have ever seen on the 2012-newer Passats are a snap ring style. EX019 is the part number for that one.

Click to expand...

Is this the correct part?

https://www.amazon.com/RKX-Compress...&ie=UTF8&qid=1475007659&sr=1-1&keywords=ex019

RKX AC Compressor Control Solenoid Valve For VOLKSWAGEN Compressors SANDEN PXE16 PXE14 MK5 MK6 B8 TDI VW
by RKX
5.0 out of 5 stars 14 customer reviews | 4 answered questions
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A/C solenoid For sanden PXE16 PXE14 compressors.
Found in many Volkswagen / Audi applications from 2006 + including TDI
OEM solenoid has an EXTREMELY high failure rate! Will cause intermittent / no AC issues
THIS IS VALVE IS SECURED INTO THE COMPRESSOR BODY USING A SNAP RING.

On my 2015 NMS Passat TDI, using pictures from the link posted by 251 on page 1 of this thread and a telescoping mirror, the snap ring can be identified from the top without removing anything.