2010 X5 4.8 mix of cool and hot air with AC

[Jonerickson]

Hi all, first post -

We have a 2010 X5 4.8 that seems to be blowing a mix of hot and cool air up front. The rear vents blow extremely cold properly however up front, the center left is the coolest, the center right, is moderate, and the litter vents, both driver and passenger are warm. What could be causing this? The AC appears to be working just fine as the rear blows very cold. This problem seems to exaggerate the warmer it is outside.

And yes, we have the control dials set to the cold setting - I’m not sure what these settings are called.

Thanks for the help!

Jon

[CSI]

Likely your blend door actuator. I'm guessing there's a thread or two on this site about its location and replacement.

[Jonerickson]

I’ve seen that a couple times across the forums. I’ve also seen the heater control valve. What’s leading you to the blend door actuator vs a heater control valve?

[Ellie13]

Originally Posted by Jonerickson

I’ve seen that a couple times across the forums. I’ve also seen the heater control valve. What’s leading you to the blend door actuator vs a heater control valve?

Jonerickson, did you ever discover/confirm this issue? Our 2013 X5 35i is having a similar problem - regardless of the temperature controls / max ac setting / auto setting - we will occasionally get VERY hot air blowing out of one side of the rear passenger vents. We cannot determine the cause as it is intermittent and never seems to be one side or the other. Sometimes it blows ice cold AC on the driver side rear, while also blowing blazing hot out of the passenger side rear (or vice versa)

One time we even noticed the VERY HOT air blowing only in the driver side footwell, while all other vents (Dashboard: left, center, right and Rear passenger both sides) still blowing cold.

It feels like we are just randomly get this where we turn on the AC and when the car gets up to temp we will just have 1 or 2 random vents start blowing super hot.

We have taken it to a local mechanic that specializes in BMW, and he said that they scanned it, there are no codes or faults, but he also mentioned that they could not replicate the issue, even when the car got up to temp. He said it COULD be the blend door actuator but he was not sure.

Any input would be appreciated!

Thanks

[Ellie13]

Update: FIXED the heat/ac issue with our 2013 X5:

We first tried topping off the refrigerant for the AC system since it was a little bit low. This made the ac colder, but we still had the issue with hot air blowing our of some vents.
I decided to try to replace the heater control valve - as many others do this when they have heat / AC issues.
For us it fixed the issue! No more random heat blowing through vents. I think over time (10 years and about 96K miles in our case) the rubber seals in the control valves just wear out and stop making a seal for the heating loop.

We choose to go with the genuine BMW part from FCP Euro ... I believe its SKU# 64116910544 which was about $200

I have also heard that the Bosch brand version of this part is good quality, but I would avoid going with other off-brands as ive read about other cheaper versions failing prematurely.

The only "special" tool I needed to complete this job was a set of "plastic hose clamp pliers" to gently clamp shut the 3 coolant hoses that connect to the heater control valve.
I bought a set of "6 pack hose clamp pliers" from Amazon for about $14 and these helped tremendously. If you dont use these hose clamps you WILL spill a ton of coolant everywhere once you disconnect the old heater control valve. Also may be a good idea to put a catch pan under the car to capture any small coolant spills while you do this part swap.

Once swapped, just make sure you top off your coolant reservoir once you have a chance to get the car up to temp and cycle the heat/ac a few times.

I hope this all helps!
M