Air Conditioner is WEAK

Ooga

Well-known member
Joined
Jul 31, 2016
Location
Washington PNW
TDI
Mk7 SportWagen
Update: Took my "new" 2015 GSW in for the 1,000 mile check-up on Saturday and the dealer recharged and tested the system. It seemed better yesterday in our humid 85 degree weather. Hopefully that's fixed it! I'll know for sure in mid-August.
I would push for them to replace some seals or I mean at least find the source of the leak. A/C refrigerant does not "run out" and the only way for the system to be undercharged is if it has a leak or wasn't ever properly charged. They can test for leaks. If they don't find any I would ask them to put the system under a vacuum and see if it holds. It is super common however for the leak to be coming from the compressor. The shaft seals are the major leak point but it was to my understanding that it wouldn't happen so soon. Shrader valves can give you some headache also.
 

2015vwgolfdiesel

Top Post Dawg
Joined
Jan 1, 2016
Location
Oklahoma
TDI
2015 VW Golf S DSG Silver
I would push for them to replace some seals or I mean at least find the source of the leak. A/C refrigerant does not "run out" and the only way for the system to be undercharged is if it has a leak or wasn't ever properly charged. They can test for leaks. If they don't find any I would ask them to put the system under a vacuum and see if it holds. It is super common however for the leak to be coming from the compressor. The shaft seals are the major leak point but it was to my understanding that it wouldn't happen so soon. Shrader valves can give you some headache also.
Shrader values?

Is that the devise in the tire stem?

Thanks
 

Funguy

Veteran Member
Joined
Jan 18, 2005
Location
Front Range of Colorado
TDI
2015 Golf Sportwagen dsg and 2015 Passat 6 M/T
Well Dad has not found his A/C to be any colder after the service by the dealer. He got around 48 degrees from the center vents with about 80 degrees outside.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Well Dad has not found his A/C to be any colder after the service by the dealer. He got around 48 degrees from the center vents with about 80 degrees outside.
With recirculate on or off?

At idle or traveling down the highway at 2000 RPM? Engine speed and airflow over the condenser both make a big difference.

If it's at idle with the recirculate off, 48 degrees is pretty good.
 

Funguy

Veteran Member
Joined
Jan 18, 2005
Location
Front Range of Colorado
TDI
2015 Golf Sportwagen dsg and 2015 Passat 6 M/T
He started out driving, outside 80 degrees a/c 48 recirculate on
Driving down the highway temp outside went to 82 a/c 50 degrees recirculate on
On the way home on the hwy still a/c 50 degrees sometimes fresh air, sometimes recirculate

On a side note my wife (who doesn't like the heat) came home yesterday with her GSW and she was NOT happy with the A/C in her car either.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
I just had my A/C refreshed in my '02 because that's what it was blowing. My GSW is much colder than that. Running the A/C on low at highway speeds last Sunday, temp outside about 80, I had to turn the thermostat up significantly because the air flow was too cold.
 

Funguy

Veteran Member
Joined
Jan 18, 2005
Location
Front Range of Colorado
TDI
2015 Golf Sportwagen dsg and 2015 Passat 6 M/T
I just had my A/C refreshed in my '02 because that's what it was blowing. My GSW is much colder than that. Running the A/C on low at highway speeds last Sunday, temp outside about 80, I had to turn the thermostat up significantly because the air flow was too cold.
I don't understand it. Some people are getting 32 degree air and others......
Dad just called me back to say that it's 96 degrees today and he ran down the highway and could not get the air below 50 with the recirculate button on etc.

The shop said that the refrigerant was a little low and they "fixed it" but no change. I wonder if the VCDS hot climate trick from earlier in this thread ,would make a difference or if that just affects engine cooling?
 

2015vwgolfdiesel

Top Post Dawg
Joined
Jan 1, 2016
Location
Oklahoma
TDI
2015 VW Golf S DSG Silver
I don't understand it. Some people are getting 32 degree air and others......
Dad just called me back to say that it's 96 degrees today and he ran down the highway and could not get the air below 50 with the recirculate button on etc.

The shop said that the refrigerant was a little low and they "fixed it" but no change. .... snip....

Seems something is wrong.

Remember my car was in continuous service from 2015 July.

Yesterday I went to the store for Braums ice cream. Temp = 95-ish

Thermostat set on "cold" speed set on "low".

Too cold after 1 mile. Have to turn the speed to off. But, only for a while.

Then adjusted the thermostat to a less "cold" setting.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
I don't understand it. Some people are getting 32 degree air and others......
Dad just called me back to say that it's 96 degrees today and he ran down the highway and could not get the air below 50 with the recirculate button on etc.
The shop said that the refrigerant was a little low and they "fixed it" but no change. I wonder if the VCDS hot climate trick from earlier in this thread ,would make a difference or if that just affects engine cooling?
It's possible that the "hot climate" function is changing the discharge air temperature set point. I haven't looked into anything newer than our 2012 Passat (which has awesome air conditioning) to verify. The Passat and the Touareg will both switch between 52F discharge and 35F discharge based on what the system feels it needs to do to maintain temperature. I wish it had more steps in between, as the alternating vent temp gets annoying on long road trips.
 

Funguy

Veteran Member
Joined
Jan 18, 2005
Location
Front Range of Colorado
TDI
2015 Golf Sportwagen dsg and 2015 Passat 6 M/T
Dad checked some more. On the Highway the car managed to go down to 45 degrees with outside temps in the 90s. When he returned to city driving the car would produce 50 degrees only

I really need to get a vcds but I always find an excuse not to. Right now I am busy remodeling the kitchen for the boss. Since I don't know what I'm doing it is slow going. When I do get one the first thing I'd like to check is this "hot climate" thing and if it changes the discharge air temperature. Really interesting stuff VeeDub, Thanks
 

Ted Hurst

Veteran Member
Joined
Jul 15, 2007
Location
44224
TDI
2015 GSW
My brand new (old) 2015 GSW has an AC issue. On my 30 minute commute home today it didn't come on until I turned it off and turned it on in my driveway. It has a major delay if it ever decides to come on. Plus it seems pretty weak when it is on. Taking it back to the Dealership next Wednesday which is the first available. GRRRRRRRRRRRRRRRR.......
Update: It was diagnosed as needing the N280 valve replaced. Part on order and will get back today or tomorrow. The Dealer could not replicate the problem on the first day so they kept it for another day. Finally got it to intermittently go warm.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
N280 is the refrigerant control valve, for what it's worth. Is VW replacing that individual part or the entire compressor? Usually they want to do the whole compressor even though the valve is replaceable separately.
 

Ted Hurst

Veteran Member
Joined
Jul 15, 2007
Location
44224
TDI
2015 GSW
Update: It was diagnosed as needing the N280 valve replaced. Part on order and will get back today or tomorrow. The Dealer could not replicate the problem on the first day so they kept it for another day. Finally got it to intermittently go warm.
Update: Dealer is replacing the whole compressor. Will report back.
 
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VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
I guess that settles it - the 2015s are plagued by the same RCV problem as all of the other TDIs dating back to 2006! Neat.
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
Springfield VA
TDI
... None :S
So here's a thought... since these cars might have sat for so long, not running, perhaps the compressor seals did let some of the R134a leak out? Those seals are designed around a turning shaft, which keeps them coated in oil. If they sit for a long time, historically, they could develop leaks.

For those with underwhelming ac performance, try this: Start the car, set the climatronic to MAX AC, turn the interior fan speed down to the 1st or 2nd setting. Go under the hood and feel the suction line at the compressor. It'll be the bigger of the 2 lines. After a little bit of running it should be COLD. If it isn't, that means either the compressor isn't pumping enough (bad RCV), or the system is low on charge. (bad radiator fans would cause this too, but I'll presume those are working and the condenser isn't plugged full of crap since these are "new" cars)

You can also log into the climate control head with VCDS and monitor the compressor request. Here's a view from our Touareg, you should be able to find similar values:



Note the Compressor Current, and Compressor Control fields. I took that screen shot with the HVAC set at minimum temp and max fan, on a hot day with the doors open. Under more normal circumstances those numbers will come down once the system "catches up" to the load. If they stay pegged out, that is another indication that either the charge is low, or the compressor control isn't working properly.

-J
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
I may try that test, or simply take mine to Kraftwerke and have Chris check the R134a level. So far I don't have any complaint about the A/C performance, but I haven't driven it in really hot weather yet. Yesterday here it was only about 80 but crazy humid. A/C on cool, no recirc, fan on 1 kept the car comfortable, no problem. But I will say that my MKIV with its newly refreshed A/C system feels colder.
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
Springfield VA
TDI
... None :S
AC gauges don't help a bunch on cars with variable displacement compressors. Seeing the high side helps for sure, but the car has a sensor for that built in :)

-J
 

Bob S.

Top Post Dawg
Joined
Aug 17, 2006
Location
Central MD.
TDI
A B4V, some ALHs & BRMs
So here's a thought... since these cars might have sat for so long, not running, perhaps the compressor seals did let some of the R134a leak out? Those seals are designed around a turning shaft, which keeps them coated in oil. If they sit for a long time, historically, they could develop leaks.

For those with underwhelming ac performance, try this: Start the car, set the climatronic to MAX AC, turn the interior fan speed down to the 1st or 2nd setting. Go under the hood and feel the suction line at the compressor. It'll be the bigger of the 2 lines. After a little bit of running it should be COLD. If it isn't, that means either the compressor isn't pumping enough (bad RCV), or the system is low on charge. (bad radiator fans would cause this too, but I'll presume those are working and the condenser isn't plugged full of crap since these are "new" cars)

You can also log into the climate control head with VCDS and monitor the compressor request. Here's a view from our Touareg, you should be able to find similar values:



Note the Compressor Current, and Compressor Control fields. I took that screen shot with the HVAC set at minimum temp and max fan, on a hot day with the doors open. Under more normal circumstances those numbers will come down once the system "catches up" to the load. If they stay pegged out, that is another indication that either the charge is low, or the compressor control isn't working properly.

-J
Jason, Thanks for sharing.

Your 7C evaporator reading converts to approx. 44.6 F, slightly above the air temps I was getting from the vents with the car moving. I suspect your reading would come down with air moving across the condenser.
 
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compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
Springfield VA
TDI
... None :S
That was on a humid, 90*F day, with the doors open, fan on full, and at idle. I was going for a "worse case" as I recharged the system.

You can see the high side is at 217 PSI. From a couple charts I found online that actually seems a bit low :eek: But that truck's AC will freeze you out, so I'm not going to diddle with it more :cool: As I was charging the system, I watched the radiator fan request. Once it started speeding the fans up I knew I was getting close.

-J
 

dieselover2

Member
Joined
Apr 27, 2017
Location
NEW MEXICO
TDI
2013 JETTA
AC on our 2013 Jetta tdi with only 64,000 miles seems to switch off on its own, even with temp setting all the way to cool. Switching the return air/outside air intake and fan speed controls does not make a difference. But, it seems to stay on for longer periods when lowering one or two windows a few inches. It cools fine when it is on, leading me to think that this is not just a need for adding refrigerant. The wire harness attachment to the compressor is intact and the splash pans under the engine are intact, so no evidence of road damage underneath. Do we have a cabin pressure sensor that is malfunctioning? Computer reset needed? ...because interestingly, we discovered (around the same time?), that if the driver's side front window is rolled all the way down, it will not roll back up without turning off and re-starting the engine.
Will try a recharge with refrigerant first and report back my findings. Does anyone have valuable input on similar problems? If the window malfunction turns out to be unrelated to the A/C, I can start a new thread on that problem.
 

Growler

Got Soot Vendor
Joined
Nov 24, 2003
Location
Millersport, Ohio
TDI
Schmutz, 2015 Golf Sportwagen DSG & Schnurren, 2001 Golf GL 2 door 5M
I can tell that my car is very much improved since i did the Hot climate change. my car also had 1000 miles on it before I owned it so it did get used more than the average ones I have seen posted here.

my car is over 6000 miles now and I havent had any other issues with weak AC since i changed it over.
 

Mike_04GolfTDI

Top Post Dawg
Joined
Nov 19, 2003
Location
Richmond, BC, Canada
TDI
Mine: 2019 Golf R DSG, Wife's: 2015 Golf Comfortline TDI
Storing vehicles for months IS a hazard.

Part I do not understand is: We do not run the A/C for 5-7 months at a time. But nothing (generally) go bad for years.

These car were "sitting" for at most, 30 months(?)

TED, let us know what happens.
In the manual for my 2004 Golf, it says to use the A/C for a few minutes once a month, even when not needed, to keep the system lubricated.

In other news, I did the "hot country" modification with VCDS on the 2015 Golf yesterday, and it does seem to make a difference.
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
I can tell that my car is very much improved since i did the Hot climate change. my car also had 1000 miles on it before I owned it so it did get used more than the average ones I have seen posted here.
my car is over 6000 miles now and I havent had any other issues with weak AC since i changed it over.

Still haven't done this, but did notice the alltrack was hovering around 45 degrees after a hot restart, took about 15 min mostly highway to get the temps back down to 40.

I'm sure its a trade off for MPG vs comfort.
 
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