Air Conditioning Air Flow Decrease After One Hour

chazmink · 09-04-2015, 04:30 PM

I've searched for this symptom but haven't found it.

On three or four occasions after an hour or so of driving with the A/C on the air flow drops of to near nothing. What is curious to me is that the fan sounds just as loud as ever but the volume from the vents is almost nil. What little air that is entering seems cool. I think the A/C has been in the manual mode on these occasions.

I had the car at the dealer a couple of days ago for an oil change and service check but they couldn't detect anything and said there were no codes. I have an appointment in a couple of weeks but don't relish the thought of them driving my car around for an hour or more in order to replicate the problem. If someone else has experienced reduced air flow and could share the solution then I could point them in the right direction.

Thanks.

tex2670 · 09-04-2015, 08:03 PM

Isn't that the point of AUTO climate control?

chazmink · 09-04-2015, 08:32 PM

Quote:

Originally Posted by tex2670

Isn't that the point of AUTO climate control?

Yes but it seems to be happening in manual.

Aatish · 09-04-2015, 09:05 PM

Do you actually put it in manual? Or are you just adjusting the intensity?

chazmink · 09-04-2015, 09:13 PM

Quote:

Originally Posted by Aatish

Do you actually put it in manual? Or are you just adjusting the intensity?

Well that's a good question. I think I usually have it in manual. Funny thing is on my 535i I think I always ran it in auto. I think what happened when I first got this car is that I found the A/C wasn't as capable so I started controlling it in manual.

DHS · 09-04-2015, 10:09 PM

Could be low freon causing the condenser to ice up.

Blubaron79 · 09-05-2015, 07:55 AM

Probably on auto recirculate, and after a while it will stop recirculating so it does not freeze up.

chazmink · 09-05-2015, 09:00 AM

Quote:

Originally Posted by Blubaron79

Probably on auto recirculate, and after a while it will stop recirculating so it does not freeze up.

This makes the most sense. Thanks!

driving0 · 09-05-2015, 06:38 PM

I have had this happen twice in my first 5k miles. Both times I was in manual mode on a low fan speed for an hour or so. Had to turn hvac completely off for a few minutes. Once I turned it back on it was normal again.

chazmink · 09-05-2015, 08:46 PM

Quote:

Originally Posted by driving0

I have had this happen twice in my first 5k miles. Both times I was in manual mode on a low fan speed for an hour or so. Had to turn hvac completely off for a few minutes. Once I turned it back on it was normal again.

Thanks. It sounds like the solution may be to use auto mode or use manual for less than an hour. It also sounds like recirc may be a contributing factor.

Heel328 · 09-05-2015, 09:11 PM

I leave the recirc set to manual ON, in the summer with AC on.

chazmink · 09-07-2015, 04:06 PM

I contacted the service advisor today to tell him what I had learned about this issue here on the forum. He told me there is a service bulletin which addresses relocation of the evaporator temperature sensor and that he can do the repair while I wait next Monday. He said they just did one last week so, perhaps, he learned about it since I was there on Monday.

Heel328 · 09-07-2015, 05:46 PM

Thanks for the update. Might apply to my car too.

Vitoco · 09-08-2015, 03:50 AM

Keep us informed, I wanna know rhe Bulletin nr

chazmink · 09-08-2015, 06:25 AM

Quote:

Originally Posted by Vitoco

Keep us informed, I wanna know rhe Bulletin nr

I think it is TSB 640613 but am not certain.

Blubaron79 · 07-15-2016, 08:22 AM

Quote:

Originally Posted by chazmink

Quote:

Originally Posted by Vitoco

Keep us informed, I wanna know rhe Bulletin nr

I think it is TSB 640613 but am not certain.

Any update on this TSB?

Billfitz · 07-15-2016, 09:44 AM

Quote:

Originally Posted by driving0

I have had this happen twice in my first 5k miles. Both times I was in manual mode on a low fan speed for an hour or so. Had to turn hvac completely off for a few minutes. Once I turned it back on it was normal again.

Classic freeze up symptom. When you turn it off the ice melts off the coils.

shivaswrath · 07-15-2016, 09:32 PM

M3s (f80s) having similar issues - ask your SA to see what's being done for them.

AudiA4 · 07-16-2016, 12:26 AM

Quote:

Originally Posted by DHS

Could be low freon causing the condenser to ice up.

This.

chazmink · 07-16-2016, 08:17 AM

I had my car at the dealer for something else but told my SA the AC acted up from time to time even after they completed the TSB. This time they found it was down a half pound in refrigerant. I'll bring it back in a month or so and hopefully the dye they put in when they recharged it will lead them to the leak.

401FlaGATOR · 07-16-2016, 09:28 AM

This forum is populated with many such complaints about the AC units which stop blowing air, a classic symptom of a frozen evaporator coil. My E90 also had an evaporator coil leak which cost 3k to repair.

I own a beater 2004 Mercury which never has had any problem with the AC over 12 years of constant use.

The automotive industry as well as the residential and commercial HVAC industry have been switching from traditional copper tube/aluminum fin construction to all aluminum microchannel evaporator coils in an effort to combat formicary corrosion and produce cheaper coils.
In the residential and commercial HVAC industry there has been a noticeable increase in leaking evaporator coils, a lot of them leaking at the point where the aluminum coil and tube transition to the copper pipe.

Why Microchannel sucks:

(Love his accent!)

I myself just had my HVAC replaced with a new microchannel unit from Nordyne (NuTone). So far so good, I hope the early failures were just that and the industry has figured these things out.
One thing with microchannel is that they don't hold much refrigerant due to the tiny channels. Therefore being 0.5 pounds low on refrigerant is a bigger deal than with a legacy system.

AndDown · 07-16-2016, 12:20 PM

Quote:

Originally Posted by 401FlaGATOR

This forum is populated with many such complaints about the AC units which stop blowing air, a classic symptom of a frozen evaporator coil. My E90 also had an evaporator coil leak which cost 3k to repair.

Why Microchannel sucks:

(Love his accent!).

This guy is flipping hilarious to listen to! Made my day viewing this video

09-04-2015, 04:30 PM	#1
chazmink First Lieutenant 93 Rep 390 Posts Drives: 2013 328i M Sport Join Date: Jul 2014 Location: Medford & LBI, NJ iTrader: (0)	I've searched for this symptom but haven't found it. On three or four occasions after an hour or so of driving with the A/C on the air flow drops of to near nothing. What is curious to me is that the fan sounds just as loud as ever but the volume from the vents is almost nil. What little air that is entering seems cool. I think the A/C has been in the manual mode on these occasions. I had the car at the dealer a couple of days ago for an oil change and service check but they couldn't detect anything and said there were no codes. I have an appointment in a couple of weeks but don't relish the thought of them driving my car around for an hour or more in order to replicate the problem. If someone else has experienced reduced air flow and could share the solution then I could point them in the right direction. Thanks. __________________ Best, Charlie 2013 328i MSport Estoril Blue, 6spd MT, Premium, Tech & Drivers Assist +, Bavsound Stage One/Ghost, Bimmertech Amp
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09-04-2015, 08:03 PM	#2
tex2670 Brigadier General 2411 Rep 4,439 Posts Drives: '23 X1 28i xDrive Join Date: Jan 2015 Location: Philly iTrader: (0) Garage List 2014 328i xDrive [0.00] 2023 X1 xDrive 28i [0.00]	Isn't that the point of AUTO climate control?
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09-04-2015, 09:05 PM	#4
Aatish Lofty 3458 Rep 849 Posts Drives: i4 M50, 991.2 C2, RRS Diesel Join Date: Dec 2013 Location: ORD <> ATX iTrader: (0)	Do you actually put it in manual? Or are you just adjusting the intensity?
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09-04-2015, 10:09 PM	#6
DHS Private First Class 43 Rep 165 Posts Drives: '16 X1, '15 435i & '98 Z3 Join Date: Jun 2008 Location: IL iTrader: (0)	Could be low freon causing the condenser to ice up.
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09-05-2015, 07:55 AM	#7
Blubaron79 Brigadier General 1432 Rep 4,723 Posts Drives: 2021 M340i xDrive Join Date: May 2009 Location: PA iTrader: (0)	Probably on auto recirculate, and after a while it will stop recirculating so it does not freeze up. __________________ Current: 2021 M340i xDrive Previous: '18 340i xDrive; '15 335 xDrive; '14 435i xDrive; '09 335 E92 xDrive
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09-05-2015, 06:38 PM	#9
driving0 New Member 2 Rep 5 Posts Drives: 320i Join Date: Feb 2012 Location: Orlando iTrader: (0)	I have had this happen twice in my first 5k miles. Both times I was in manual mode on a low fan speed for an hour or so. Had to turn hvac completely off for a few minutes. Once I turned it back on it was normal again.
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09-05-2015, 09:11 PM	#11
Heel328 First Lieutenant 79 Rep 369 Posts Drives: 2013 328i 6MT Join Date: Mar 2015 Location: Carolina iTrader: (0)	I leave the recirc set to manual ON, in the summer with AC on. __________________ 2013 328i 6MT 1995 S6* 1993 S4* 1984 944* 1988 16V GTI*
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09-07-2015, 04:06 PM	#12
chazmink First Lieutenant 93 Rep 390 Posts Drives: 2013 328i M Sport Join Date: Jul 2014 Location: Medford & LBI, NJ iTrader: (0)	I contacted the service advisor today to tell him what I had learned about this issue here on the forum. He told me there is a service bulletin which addresses relocation of the evaporator temperature sensor and that he can do the repair while I wait next Monday. He said they just did one last week so, perhaps, he learned about it since I was there on Monday. __________________ Best, Charlie 2013 328i MSport Estoril Blue, 6spd MT, Premium, Tech & Drivers Assist +, Bavsound Stage One/Ghost, Bimmertech Amp
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09-07-2015, 05:46 PM	#13
Heel328 First Lieutenant 79 Rep 369 Posts Drives: 2013 328i 6MT Join Date: Mar 2015 Location: Carolina iTrader: (0)	Thanks for the update. Might apply to my car too. __________________ 2013 328i 6MT 1995 S6* 1993 S4* 1984 944* 1988 16V GTI*
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09-08-2015, 03:50 AM	#14
Vitoco Infidel 122 Rep 1,102 Posts Drives: iX3 LCI M Pro Carbon B Join Date: Mar 2012 Location: Sweden iTrader: (0)	Keep us informed, I wanna know rhe Bulletin nr __________________ Dec. 2022: Fully loaded Carbon Black G08 iX3 LCI M Sport Pro Former: Glacier Ag. F31 328iA RWD M Sport oct. 2012, sold July 2022 \| Sport Automatic \| Adap. M Susp. \| Pano. Moonroof \| 20" ATS Racelight Grey w. Michelin PSS\| M Sport brakes \| Harman Kardon \| Elec. Seats \| PDC F&R \| ACC Stop&Go \| 335i MPE \| Perf. Parts \|
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07-15-2016, 09:32 PM	#18
shivaswrath Brigadier General 649 Rep 4,323 Posts Drives: 2012 335i Join Date: Apr 2008 Location: Lost in NJ iTrader: (3)	M3s (f80s) having similar issues - ask your SA to see what's being done for them. __________________ CURRENT: 2017 RS3 (miss you guys) SOLD: 2012 335i Mineral Gray M Performance Exhaust/Brakes/Suspension/LSD\|Bav Stage 1/AMP\|\|ER CP/IC/DP/OC \| Dinan CAI/N55 PWG BIG TURBO\|BMWF30.com
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07-16-2016, 08:17 AM	#20
chazmink First Lieutenant 93 Rep 390 Posts Drives: 2013 328i M Sport Join Date: Jul 2014 Location: Medford & LBI, NJ iTrader: (0)	I had my car at the dealer for something else but told my SA the AC acted up from time to time even after they completed the TSB. This time they found it was down a half pound in refrigerant. I'll bring it back in a month or so and hopefully the dye they put in when they recharged it will lead them to the leak. __________________ Best, Charlie 2013 328i MSport Estoril Blue, 6spd MT, Premium, Tech & Drivers Assist +, Bavsound Stage One/Ghost, Bimmertech Amp
	Appreciate 0 Quote

07-16-2016, 09:28 AM	#21
401FlaGATOR First Lieutenant 70 Rep 328 Posts Drives: E90 325i ZSP, F30 320i ZSP Join Date: Oct 2006 Location: Pembroke Pines, FL iTrader: (0)	This forum is populated with many such complaints about the AC units which stop blowing air, a classic symptom of a frozen evaporator coil. My E90 also had an evaporator coil leak which cost 3k to repair. I own a beater 2004 Mercury which never has had any problem with the AC over 12 years of constant use. The automotive industry as well as the residential and commercial HVAC industry have been switching from traditional copper tube/aluminum fin construction to all aluminum microchannel evaporator coils in an effort to combat formicary corrosion and produce cheaper coils. In the residential and commercial HVAC industry there has been a noticeable increase in leaking evaporator coils, a lot of them leaking at the point where the aluminum coil and tube transition to the copper pipe. Why Microchannel sucks: (Love his accent!) I myself just had my HVAC replaced with a new microchannel unit from Nordyne (NuTone). So far so good, I hope the early failures were just that and the industry has figured these things out. One thing with microchannel is that they don't hold much refrigerant due to the tiny channels. Therefore being 0.5 pounds low on refrigerant is a bigger deal than with a legacy system.
	Appreciate 0 Quote