robdog
Well-known member
So 18.75 oz. of freon is what the 06 takes? Mine is missing all labels under the hood and I plan to swap the valve this weekend.
Thanks, Rob
Thanks, Rob
A/C Compressor Refrigerant Control Valve
- Thread starter kfcoltn
- Start date
10then34
Veteran Member
My '06 is in a local shop right now. It had a weak AC for a long time, while I had it in to get the alignment checked, I thought what the heck, have them recharge the AC. Big mistake. They called me that the pressure is low and that they suggest to vacuum and charge it. I gave them the go-ahead and now they are telling me that 'there is a blockage' and they can't get the system charged 
.
Any thoughts from the more AC savy. I had a 'AC pressure high' code at some point but it didn't reappear after I cleared it. Could I have a clogged expansion valve rather than just a low refrigerant level ?
Allright, update. Now it is charged and works like a charm while the engine is running, but for some reason the radiator fans dont kick on with the car idling. It looks like the signal for the radiator fan to come on doesn't get to the fan itself.
Vag-com doesn't have any codes. Is there a relais somewhere that could have failed ?
. Any thoughts from the more AC savy. I had a 'AC pressure high' code at some point but it didn't reappear after I cleared it. Could I have a clogged expansion valve rather than just a low refrigerant level ?
Allright, update. Now it is charged and works like a charm while the engine is running, but for some reason the radiator fans dont kick on with the car idling. It looks like the signal for the radiator fan to come on doesn't get to the fan itself.
Vag-com doesn't have any codes. Is there a relais somewhere that could have failed ?
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DanG144
Top Post Dawg
The refrigerant high pressure has to build up to about 10 bar before the fans will be asked to kick on.
You will see them on at idle during hot weather, but not during cold weather.
Sounds normal to me.
The VW gauge attach points are problematic. I had to buy a gauge set that had adjustments on the the attach points in order to reliably get the gauges to work.
You will see them on at idle during hot weather, but not during cold weather.
Sounds normal to me.
The VW gauge attach points are problematic. I had to buy a gauge set that had adjustments on the the attach points in order to reliably get the gauges to work.
PalmettoDub
Active member
I have a basic series of questions, sorta! 09 TDI Jetta. I turned the key on today and the AC button was on. I opened the hood and noticed no fans running. So I started it and checked again. NO fans running, AC switched on. Warm air out of dash. I let it sit for a good half hour, still no fans, no cold. I have been reading that this valve is fixing all the problems. Does this valve happen to control the fans as well? My concern is that I have researched the SMALL fan not working, FCM, and this prevents the AC from coming on. Can it work the other way? I would hate to put the small fan in and still need the valve. Any ideas on basic tests to check?
Thanx and sorry to babble.
Thanx and sorry to babble.
DanG144
Top Post Dawg
Both fans should always run together, at the same speed.
The fans are tasked to start AFTER the AC pressure has increased.
If the AC refrigerant control valve is not working (or if anything else prevents the AC compressor from producing more than 150 psig) then the fans will not come on.
You can test your fans with VCDS, engine module, output tests.
The fans are tasked to start AFTER the AC pressure has increased.
If the AC refrigerant control valve is not working (or if anything else prevents the AC compressor from producing more than 150 psig) then the fans will not come on.
You can test your fans with VCDS, engine module, output tests.
PalmettoDub
Active member
So that would explain the intermittent AC usage? It is random and there is no consistent span of usage. Sometimes when im at idle its off, or rolling along at 45 or 75. That does sound more of a pressure problem. I would assume that if the FCM was bad it wouldnt work at all?
DanG144
Top Post Dawg
If your FCM (which is truly only a fan control module on the mk V, unlike the earlier mk IV systems where it was a fan and AC control module) was bad, then your AC would consistently work well at highway speeds, would have no delay on startup, but would become ineffective soon after startup at slow speeds. The FCM on the Mk V is built into the back of the large fan.
The behavior you describe is USUALLY attributable to a bad RCV. You have to test to PROVE it.
That being said, its so often the RCV that I would not spend a lot of money or time to prove it - I would just buy one and put it in. Since I have the VCDS, and the gauges, it is cheap and quick to see for sure what the problem is.
The behavior you describe is USUALLY attributable to a bad RCV. You have to test to PROVE it.
That being said, its so often the RCV that I would not spend a lot of money or time to prove it - I would just buy one and put it in. Since I have the VCDS, and the gauges, it is cheap and quick to see for sure what the problem is.
PalmettoDub
Active member
Thank you, going with the valve!
Hi Dan.
I hope you don't mind me jumping in on this thread but I've just had a $2000 quote from VW to replace my entire a/c system due to an (allegedly) expired compressor and your quote above has raised a question....
My fans come on at high speed immediately when I turn the a/c on (2007 with climatronic). If my compressor was totalled (working 100% fine up to last week then complete loss of all a/c function, no bangs or smoke, just no cooling at all), would it be able to generate the necessary psi to trigger the fan operation? Do you think this fan behaviour might point to an RCV problem rather than a dead compressor?
I have VCDS so can check details but I'm just at the very start of what I fear will be a long & expensive journey learning about VW a/c so I'm not entirely sure what to look for but this thread is proving to be a great starting point.
Thanks.
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DanG144
Top Post Dawg
Sweaty,
As with most brief statements mine above is a simplification and with certain assumptions. One of which was that the system is a climatic, rather than a climatronic. The climatronic is much more complicated, and I have little experience with it.
The symptoms you describe would seem to me to likely be a failed high pressure sensor. It could also be in response to your ECU thinking that your engine is running way too hot.
You need to do some diagnostics with VCDS and a set of AC pressure gauges.
You are right to question the diagnosis. If it were me, I would fear that they might replace the entire system and still not fix the problem.
As with most brief statements mine above is a simplification and with certain assumptions. One of which was that the system is a climatic, rather than a climatronic. The climatronic is much more complicated, and I have little experience with it.
The symptoms you describe would seem to me to likely be a failed high pressure sensor. It could also be in response to your ECU thinking that your engine is running way too hot.
You need to do some diagnostics with VCDS and a set of AC pressure gauges.
You are right to question the diagnosis. If it were me, I would fear that they might replace the entire system and still not fix the problem.
Inside the Refrigerant Control Valve (RCV)
Hello all, My A/C simply quit the other day, prompting an investigation, mostly to learn about it.
My first indication of a bad RCV valve was working fans, working A/C button lights, but simply warm air. The pressure also read 82psi (static) on the low side......Way too much!!!! There was also a gurgling sound in the dash when turning off the A/C.
The low side service port is the line closest to the fender, with the larger diameter (3/4") aluminum line.
After a safe recovery of the refrigerant in the system, the valve can be removed:
.
The snap ring style is easily accessed with a 90 degree pair of snap ring pliers. The valve is tricky to get out. You will break off the plastic top hat and connector if you pry too hard!! Wiggle it, rotate it and as a last resort, 10 psi of clean, dry air introduced into the low pressure service port will help to push the valve out!!!!
.
Only a drip or 2 of smelly oil comes out. Note the bubbly air filled oil!!! The picture makes it look like metal fragments, but thats only bubbles. There are metal fragments, but very small.
.
.
There was a little bit of tiny metal debris on the valve and the filter. Most likely normal wear from the 150k (km's) on my compressor.
Here's where it would be easy to simply insert a new valve, but I wanted to find out what failed!!!!
The valve is a Pulse Width Modulated (PWM) controlled solenoid valve, varying the displacement of the compressor, via the swashplate angle. It allows pressure to act, or relax the swashplate, depending on Duty cycle, commanded by the ECM.
The solenoid part is simple, easily checking the resistance.
.
11.2 ohms.
Next was to see what stuck???
There is a small plunger and spring under an adjustable set screw:
.
.
Measured the depth of the set screw to allow accurate reassembly:
.
Now the little plunger was stuck, probably from tiny metal fragments. It easily came out with a gentle banging on a block of wood.
.
.
I cleaned everything and reassembled with a dab of loctite on the set screw to retain it.
The three Orings got an inspection and lubed up, ready to test!!!
Testing:
For bench testing, I used a low amperage 12 volt DC power supply and "clicked" the solenoid. It moves very positive and travels the plunger about 1/16". Before cleaning, the plunger did not move at all.
Here's a vid:
http://i1059.photobucket.com/albums...62BF306-1867-000001B64860F12A_zpse9c0ceb6.mp4 .
.
I re-installed the valve into the compressor and charged with almost 19 Oz to 36 psi, on the low side, while running.
Ice cold again!!
A new valve is not that expensive, I just wanted to determine what sticks in the valve and have a better understanding of the system.
Hope this helps avoid an expensive repair for someone else!!!
All the best,
Andrew
Hello all, My A/C simply quit the other day, prompting an investigation, mostly to learn about it.
My first indication of a bad RCV valve was working fans, working A/C button lights, but simply warm air. The pressure also read 82psi (static) on the low side......Way too much!!!! There was also a gurgling sound in the dash when turning off the A/C.
The low side service port is the line closest to the fender, with the larger diameter (3/4") aluminum line.
After a safe recovery of the refrigerant in the system, the valve can be removed:
The snap ring style is easily accessed with a 90 degree pair of snap ring pliers. The valve is tricky to get out. You will break off the plastic top hat and connector if you pry too hard!! Wiggle it, rotate it and as a last resort, 10 psi of clean, dry air introduced into the low pressure service port will help to push the valve out!!!!
Only a drip or 2 of smelly oil comes out. Note the bubbly air filled oil!!! The picture makes it look like metal fragments, but thats only bubbles. There are metal fragments, but very small.
.
There was a little bit of tiny metal debris on the valve and the filter. Most likely normal wear from the 150k (km's) on my compressor.
Here's where it would be easy to simply insert a new valve, but I wanted to find out what failed!!!!
The valve is a Pulse Width Modulated (PWM) controlled solenoid valve, varying the displacement of the compressor, via the swashplate angle. It allows pressure to act, or relax the swashplate, depending on Duty cycle, commanded by the ECM.
The solenoid part is simple, easily checking the resistance.
11.2 ohms.
Next was to see what stuck???
There is a small plunger and spring under an adjustable set screw:
Measured the depth of the set screw to allow accurate reassembly:
Now the little plunger was stuck, probably from tiny metal fragments. It easily came out with a gentle banging on a block of wood.
I cleaned everything and reassembled with a dab of loctite on the set screw to retain it.
The three Orings got an inspection and lubed up, ready to test!!!
Testing:
For bench testing, I used a low amperage 12 volt DC power supply and "clicked" the solenoid. It moves very positive and travels the plunger about 1/16". Before cleaning, the plunger did not move at all.
Here's a vid:
http://i1059.photobucket.com/albums...62BF306-1867-000001B64860F12A_zpse9c0ceb6.mp4 .
.
I re-installed the valve into the compressor and charged with almost 19 Oz to 36 psi, on the low side, while running.
Ice cold again!!
A new valve is not that expensive, I just wanted to determine what sticks in the valve and have a better understanding of the system.
Hope this helps avoid an expensive repair for someone else!!!
All the best,
Andrew
d2305
Veteran Member
Nice pics. I need to look at mine.
Paulinski
Veteran Member
Thanks for the pics Andrew.
DanG144
Top Post Dawg
I have yet to find an open solenoid coil; it always appears stuck. Thanks for the tutorial on disassembly.
Looks like we are all winning today.
This morning a local independent shop found my lack of a/c was down to a simple leaking pressure sensor, the whole thing was fixed & back on the road freezing cold within 1.5 hrs for under $400 (I know I could have done it cheaper myself but under the circumstances, I'm very happy with this).
Without the info in this forum & others like it I would have not questioned the diagnosis from a major VW dealership that the car needed a whole new a/c system due to compressor failure and I would be well on my way to being $2000 poorer.
Hope the good a/c karma continues to spread, may your journeys be cold & your repair bills be small.
Better change my username now.....
This morning a local independent shop found my lack of a/c was down to a simple leaking pressure sensor, the whole thing was fixed & back on the road freezing cold within 1.5 hrs for under $400 (I know I could have done it cheaper myself but under the circumstances, I'm very happy with this).
Without the info in this forum & others like it I would have not questioned the diagnosis from a major VW dealership that the car needed a whole new a/c system due to compressor failure and I would be well on my way to being $2000 poorer.
Hope the good a/c karma continues to spread, may your journeys be cold & your repair bills be small.
Better change my username now.....
toddman35
Well-known member
A heads up for anyone with the bolted in version - it doesn't appear to come apart nearly as simply as the snap ring version. After ordering the snap ring RCV from Polar I realized that I need the bolt one. I blew off the screen with clean compressed air, verified movement when applying 12v and measured 11.9 ohms across it before reinstalling it and after a recharge I've got cold air again.
Evacuating the system only pulled 8oz of freon out so my issue was not due to RCV failure. Where are common leak points in the A5?
Anyone need a brand new snap ring RCV?
Evacuating the system only pulled 8oz of freon out so my issue was not due to RCV failure. Where are common leak points in the A5?
Anyone need a brand new snap ring RCV?
Nice job Andrew!
The number and frequency of these failures now makes a lot more sense, that this part just gets fouled up over time, rather than being defective.
It makes you wonder how many people have been duped over the years into buying whole new A/C systems, when it could have been a simple, easy, and inexpensive fix like this.
The number and frequency of these failures now makes a lot more sense, that this part just gets fouled up over time, rather than being defective.
It makes you wonder how many people have been duped over the years into buying whole new A/C systems, when it could have been a simple, easy, and inexpensive fix like this.
meerschm
Top Post Dawg
- Joined
- Apr 18, 2009
- Location
- Fairfax county VA
- TDI
- 2009 Jetta wagon DSG 08/08 205k buyback 1/8/18; replaced with 2017 Golf Wagon 4mo 1.8l CXBB
I saw another thread that suggested that some of these may have been underfilled with refrigerant from the assy line.
Since I do not think any of us has evacuated the system when it is new to measure the factory load, it would be hard to tell.
Update: August 2016. shop I had recover R134a said there was 1.1 pounds in the system. that would be 17.6 ounces, within spec for
525 grams plus or minus 25 grams (500 grams is just over 17.6 oz) this is after putting 170,000 miles on the car. (and no previous system maintenance except me putting a gauge set on twice for grins. (which probably leaked a bit.)
Since I do not think any of us has evacuated the system when it is new to measure the factory load, it would be hard to tell.
Update: August 2016. shop I had recover R134a said there was 1.1 pounds in the system. that would be 17.6 ounces, within spec for
525 grams plus or minus 25 grams (500 grams is just over 17.6 oz) this is after putting 170,000 miles on the car. (and no previous system maintenance except me putting a gauge set on twice for grins. (which probably leaked a bit.)
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d2305
Veteran Member
Hello All, following up and adding to information from post # 42, page 3.
This is interesting, so I rounded up a couple of different Snap Ring and bolted styles. The bolted in style does not have a set screw adjustment to capture the spring and plunger. However, you can carefully remove it with a dental pick, if you wish to clean it, or see why it failed.
Snap ring style left, bolt in style right.
Spring easily winds out, allowing plunger to be "unstuck" cleaned and re-installed.
Again, the valve is only $75 max, but it feels great to understand why it fails and certainly have a spare on the shelf!!!
All the best,
Andrew
Texas-Rebel
Active member
Does this fix the 5-10 minute delay before the A/C gets cold upon engine startup? My A/C gets real cold after 5-10 minutes upon turning it on. It's either a 5 minute wait or a 5 mile wait. This is in a 2009 Jetta TDI.
Going through this now. On the bench, when I hit it with 12 volts, it clicks over every time. This is what mine looks like, no way I can see to get to the spring. Maybe mine is unserviceable? Either way, not sure where to go from here. Probably put the valve back in, recharge it and see what happens.
Very good to see another style!! Very curious which brand of compressor you have??Going through this now. On the bench, when I hit it with 12 volts, it clicks over every time. This is what mine looks like, no way I can see to get to the spring. Maybe mine is unserviceable? Either way, not sure where to go from here. Probably put the valve back in, recharge it and see what happens.
If you don't have another valve, sure, try cleaning this one with air and flush it with your favorite cleaner.That screen should gently slide off to expose the inlet ports.
Protect the orings from solvent and blow air while clicking the solenoid.Try to make sure you can see the plunger and / or spring moving in and out.
Kudos to you, offering your car and time in the name of science!!!
All the best,
Andrew
Should have provided more information. This is a snap ring style, from a Sanden compressor, car is an 11 JSW. I can see the spring compress about 1/8 of an inch when I hit it with voltage. The end piece doesn't move at all. I've pushed on it pretty hard, and I don't think it moved.
Runnerguy45
Veteran Member
After reading this thread I ordered a RCV from Polar AC and my guru put RCV in and my AC is working better then ever. My guru has also taken information about Polar as he had three cars in last week with same issue. Dan thank you so much for sharing information. This website has saved me a ton of money.
1998993C2S
Veteran Member
priceless ! Thanx.hello all, my a/c simply quit the other day, prompting an investigation, mostly to learn about it.
My first indication of a bad rcv valve was working fans, working a/c button lights, but simply warm air. The pressure also read 82psi (static) on the low side......way too much!!!! There was also a gurgling sound in the dash when turning off the a/c.
The low side service port is the line closest to the fender, with the larger diameter (3/4") aluminum line.
After a safe recovery of the refrigerant in the system, the valve can be removed:
.
The snap ring style is easily accessed with a 90 degree pair of snap ring pliers. The valve is tricky to get out. You will break off the plastic top hat and connector if you pry too hard!! Wiggle it, rotate it and as a last resort, 10 psi of clean, dry air introduced into the low pressure service port will help to push the valve out!!!!
.
Only a drip or 2 of smelly oil comes out. Note the bubbly air filled oil!!! The picture makes it look like metal fragments, but thats only bubbles. There are metal fragments, but very small.
.
.
There was a little bit of tiny metal debris on the valve and the filter. Most likely normal wear from the 150k (km's) on my compressor.
Here's where it would be easy to simply insert a new valve, but i wanted to find out what failed!!!!
The valve is a pulse width modulated (pwm) controlled solenoid valve, varying the displacement of the compressor, via the swashplate angle. It allows pressure to act, or relax the swashplate, depending on duty cycle, commanded by the ecm.
The solenoid part is simple, easily checking the resistance.
.
11.2 ohms.
Next was to see what stuck???
There is a small plunger and spring under an adjustable set screw:
.
.
Measured the depth of the set screw to allow accurate reassembly:
.
Now the little plunger was stuck, probably from tiny metal fragments. It easily came out with a gentle banging on a block of wood.
.
.
I cleaned everything and reassembled with a dab of loctite on the set screw to retain it.
The three orings got an inspection and lubed up, ready to test!!!
Testing:
For bench testing, i used a low amperage 12 volt dc power supply and "clicked" the solenoid. It moves very positive and travels the plunger about 1/16". Before cleaning, the plunger did not move at all.
Here's a vid:
http://i1059.photobucket.com/albums...62bf306-1867-000001b64860f12a_zpse9c0ceb6.mp4 .
.
I re-installed the valve into the compressor and charged with almost 19 oz to 36 psi, on the low side, while running.
Ice cold again!!
A new valve is not that expensive, i just wanted to determine what sticks in the valve and have a better understanding of the system.
Hope this helps avoid an expensive repair for someone else!!!
All the best,
andrew
Cougar281
Well-known member
That's a very interesting picture... My Wife's 2010 TDI, with a Sanden Model 1601 compressor (VW P/N 1K0 820 859 Q), has a snap in valve with the set screw style valve, but the plunger inside it was sort of a cross between the two in the picture - it was almost identical to the one on the right in your picture, but the 'nib' on top that the spring sits on was a touch longer.
Also real interesting is the valve I ordered from Autozone was listed as being for the PXE13/PXE16 compressors (Autozone part number MT2282), but it was totally different than the one in the car. According to Sanden's website, the Model 1601 is a PXE16. Also according to their website the 2010 TDI is supposed to have a model 4573, which is also a PXE16.
The control valve that's in the car, from everything I can find, is the control valve that you'd find in a PX16 compressor, not a PXE16.
At any rate, while it was out, my friend and I took it apart and cleaned it up - there was debris inside it and the plunger definitely was sticky initially - cleaned it all up and put it back together and initially, the AC was working right. We shut it down to heat load the cabin and test how well it removed the heat, and when we turned the A/C back on - nothing. So I need to order the right part and return the wrong one.
Why couldn't they just stick to the tried and true clutch driven compressor??
Does anyone have any thoughts as to what the story is here?
Also real interesting is the valve I ordered from Autozone was listed as being for the PXE13/PXE16 compressors (Autozone part number MT2282), but it was totally different than the one in the car. According to Sanden's website, the Model 1601 is a PXE16. Also according to their website the 2010 TDI is supposed to have a model 4573, which is also a PXE16.
The control valve that's in the car, from everything I can find, is the control valve that you'd find in a PX16 compressor, not a PXE16.
At any rate, while it was out, my friend and I took it apart and cleaned it up - there was debris inside it and the plunger definitely was sticky initially - cleaned it all up and put it back together and initially, the AC was working right. We shut it down to heat load the cabin and test how well it removed the heat, and when we turned the A/C back on - nothing. So I need to order the right part and return the wrong one.
Why couldn't they just stick to the tried and true clutch driven compressor??
Does anyone have any thoughts as to what the story is here?
Hello All, following up and adding to information from post # 42, page 3.
This is interesting, so I rounded up a couple of different Snap Ring and bolted styles. The bolted in style does not have a set screw adjustment to capture the spring and plunger. However, you can carefully remove it with a dental pick, if you wish to clean it, or see why it failed.
.
Snap ring style left, bolt in style right.
Spring easily winds out, allowing plunger to be "unstuck" cleaned and re-installed.
Again, the valve is only $75 max, but it feels great to understand why it fails and certainly have a spare on the shelf!!!
All the best,
Andrew
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I had my RCV replaced today, and the original/factory valve was identical to the one in these pics. 2010 Jetta, Sanden 1601 compressor. The replacement valve from Polar was the shorter version, with the hole and set screw in the end. The A/C now works better than ever. It blows cold air upon start-up, and stays cold.
The compressor is now running quiet and smooth. The technician showed me the pressures on the high and low side prior to evacuation, and there was way too much head pressure on the low side. I suspect the compressor was having to work much harder than it should have been prior to replacing the valve.
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