Steam out the center vents!

[X5chemist]

A 337 mile drive after being parked for 5 months, I get a scare of a lifetime. About half way home, the center vents start to vent steam! Definitely, not coolant. A/C was set at 60 and lowest fan speed. Air vent temp was 42 degrees. I pull into a gas station fast after turning off the A/C. I let it cool a few minutes. Open the hood, nothing found. Engine temp was right in the middle. No leaks found. The A/C drain area was definitely wet. Take off and coolant temps remained the same. I drove in pan roof vent mode since it was a cool morning. Later on once the sun came up, I turned the A/C back on. No issues for 200+ miles.

Could enough condensation have been collected to reach the heater core area? Being parked for 5 month, bugs may have clogged up the drain hose. I'll check it next weekend. Feels great to have the X5 back.

[nick325xit 5spd]

it does happen in the right atmospheric conditions. especially if it’s really humid out.

[stiubhartach]

I’ve seen it happen with a pinhole in a heater core. If it smells sweet, then it’s coolant.

[X5chemist]

I checked the coolant level yesterday. The float indicator is right on the top end. No issues since the first time. I'll check it every few days just in case. If it's a heater core problem, I won't know until winter. A replacement heater hose valve is ready to go in incase the OEM one fails.

[srmmmm]

I worked for Zexel and Behr Climate Systems for 11 years, both automotive and truck HVAC suppliers. The "cloud" you saw exiting the center vents is not steam, but condensed water vapor. In cooler ambient temperatures, the evaporator core can develop a "supercooled" state when the refrigerant charge is low. The refrigerant is expanding more than normal because the low pressure side of the system is too low, creating a colder than normal evaporator core temperature. I've actually seen ice crystals blow out of car vents under these conditions and the evaporator core freeze over completely.


Check your refrigerant levels and I suspect you'll find it low.

[nick325xit 5spd]

Originally Posted by srmmmm

I worked for Zexel and Behr Climate Systems for 11 years, both automotive and truck HVAC suppliers. The "cloud" you saw exiting the center vents is not steam, but condensed water vapor. In cooler ambient temperatures, the evaporator core can develop a "supercooled" state when the refrigerant charge is low. The refrigerant is expanding more than normal because the low pressure side of the system is too low, creating a colder than normal evaporator core temperature. I've actually seen ice crystals blow out of car vents under these conditions and the evaporator core freeze over completely.


Check your refrigerant levels and I suspect you'll find it low.

Or if your evap temp sensor isn't working correctly. I was loving the AC in my E30 M3 for the 10-15 minutes it took to freeze the evaporator when it was blowing 19 degrees.

[grounch]

Happened to me too once, i think the conditions were hot weather, used AC for some time and when turned it off but kept vents working.
Weird feeling to see smoke / steam coming from all the vents, reminds the Charger in the ending of Fast and Furious. But as it had zero smell and only created some dropplets on the vents, it seemed obvious that it's no big deal.

[X5chemist]

Ok, so it does happen. It has been over a year since I gave it a R134 boost. I did it after installing a new auxiliary brushless fan. Since it was parked for 5 months waiting on suspension updates and oil pan gasket work, it was not driven in Texas 100+ degree days this year. Feels great using 60 temp setting and lowest fan speed to keep cool. Ceramic window tinting helps too! Even the pano roof is tinted dark.

[Bottomfeeder]

This happened to me once on my 2005 X5 3.0 about two years ago.

It was a very hot day, Austin traffic, lasted about 10 seconds or so and startled the hell out of me! Like you, there was definitely no coolant smell or incriminating smell of any kind that I could detect. Though it did look like steam or even smoke, it wasn't warm and the AC never went out or stopped cooling properly.

I expected the worst and waited to see if it would happen again (or the AC fail altogether in some way) but it hasn't yet.

Chris
2005 X5 3.0 - Jet black
2002 X5 3.0 - Titan silver

[X5chemist]

Originally Posted by srmmmm

Check your refrigerant levels and I suspect you'll find it low.

srmmmm,
Thanks for your info. I hooked up hoses on Friday. Readings were weird. I know there was a leak as soon as the caps came off. Both valve cores turned enough to feel them snug up a frog hair.
A 30 min vacuum was pulled on it. Vacuum didn't reach my desired Hg reading due to high humidity. Possible old gauges being faulty too. The first can went in good with vacuum. The can remaining portion was sucked in when the compressor kicked on. The second can was put in slowly. Trying to get 430-450 grams in is no easy task without a scale. To my surprise, the auxiliary fan kicked on before reaching engine operating temperature. The temp was about half way to mid point. Low sided ended up at ~43 PSI. High side cycled 225+. If the auxiliary fan continues to kick on, it will solve my cooling down issue. No more immediate drive off if the engine is not to normal operating temps.