[Flyboy777]

Been bugging me a while now,
Heater set to auto, 22c both sides, all vents open, centre vent temperature control set cold, recirc in auto.
Cruising along all fine with comfortable face level airflow when suddenly the face level vents blow very cold for 2-3 minutes then all returns to normal. Same happens approx every 10-15 minutes after the first occurance which may not initially happen for 40 or so minutes.
Nothing changed with any settings during the journey and no noticeable change to outside air temperature, level of sunlight or wipers being turned on.
Just appears as a regular but random pulse of freezing cold face level airflow.
This on a 2015 LCI F31.
Anyone else had this happen as it is becoming annoying now?

[Drek]

Happens to me as well, also used to happen on my old E91 too. I usually push the wheel to its warmest setting then gradually wheel it back again until it's comfortable.

[pdk42]

Yea - mine does that too.

[Flyboy777]

Annoying but at least no point in wasting time with the dealer.
Came from a 1 series--- no face level adjust wheel and the HVAC system was perfect, never had to fiddle, just left in auto to do it's thing except if defrosting ice first thing.
A bit disappointing but guess I just have to live with it then.

[creepy coupe]

They do this from time to time. i think it's the HVAC system dealing with excess moisture.

[ep22jg]

Mine used to do this, but is better now!
I read on hear that there was a software update which sorted it

I had trouble with my dash and the dealer said they'd updated the software. This did nothing for the dash problem but has helped the AC!!

So I can only assume that there is a software fix for this!!

[NickB]

Mine does the same - on a very intermittent basis (sometime not for several weeks).

Can’t work out why as does not appear to be linked to exterior temperature, sunlight, rain etc...

[G82Dude]

Yea, very annoying that it engages the a/c on its own, without being in either "auto" or a/c on! "Normal" behaviour apparently.

[Rich9600]

Interesting thread. I've never had this happen in either my E90 or F30. However, for OCD reasons I like my dial centred...

Does this only happen when max cooling is selected for the face level vents?

If so, could it be an icing issue, giving you max cooling until it ices up? Then defrosting and starting again?

[NickB]

Dial position makes no difference. Only way to stop to cold blast of air is to turn the temperature up.

Usually sorts itself out after a few minutes - and then may not reoccur for several weeks.

[moonshine]

i raised this issue on the forum in March
http://f30.bimmerpost.com/forums/sho....php?t=1239514

[Rich9600]

Sounds like the thermostatic action slightly lagging and needing to overcompensate. This is then amplified by user settings of the centre dial. Resulting in a blast of hot or cold air depending on the circumstances and settings.

[ChaserPlus]

Had this for a few months. Booked it in under warranty last week. Picked it up last Friday and it's now fixed. Software update is all that's needed.

[evdok]

This is a safety issue, it blows cold air out if it detects you getting tired

[creepy coupe]

Originally Posted by ChaserPlus

Had this for a few months. Booked it in under warranty last week. Picked it up last Friday and it's now fixed. Software update is all that's needed.

Really? he last three BMW's I've had have done this.

[evdok]

I noticed this on Sunday, as it was raining the bottom of the windscreen started to mist up but after a few seconds i could feel the a/c work its magic & the screen would clear up, i had the circulation button on AUTO, I'm pretty sure this is what its meant to do if you have the circulation on AUTO.

[mtx450]

Yep, my 2016 340i does this as well. I find that it happens with AUTO turned off and A/C turned off as well. So there is some sort of automagicness happening.

I'm assuming it detects some sort of moisture and quickly engages the A/C to deal with it? But that's just a guess so I don't actually have any idea.

[NISFAN]

The air con compressor 'cycles'. i.e it is not continuously running. It cools the evaporator down and then switches off until the system requires it to do its thing again. I'm thinking you are sensing when the compressor kicks back in and cools the evaporator, causing a sudden reduction in temperature.

This software update could just be reducing the tolerance of when the compressor needs to kick back in, effectively making it run more frequently with less of a delta in temperature.

I would imagine that Ecopro would make this sensation worse as it supposedly reduces air on compressor function.

[ChaserPlus]

Originally Posted by creepy coupe

Really? he last three BMW's I've had have done this.

This is my 5th BMW and only had problems with the one. I thought BMW were just fobbing me off when they said software update. But it's been really good, nothing but cool or warm air. Comfortable.

[alpine330D]

My climate control is very much like a woman, i will never ever understand it.

[moonshine]

Originally Posted by ChaserPlus

Had this for a few months. Booked it in under warranty last week. Picked it up last Friday and it's now fixed. Software update is all that's needed.

My car was in the dealer for a number of issues to be looked at and this was one of them - dealer has confirmed there is a software update to reprogram the A/C pump to address this issue - will get it done next week when car is in to get MAF, EGR cooler, fuel pump and 2 rear wheels replaced....

[JustChris]

Originally Posted by moonshine

i raised this issue on the forum in March
http://f30.bimmerpost.com/forums/sho....php?t=1239514

Same, had this on several different F series cars, F10, F30, F22.

Hoping F15 is different HVAC system!