strange heat problem [Archive] - Bimmerfest - BMW Forums

: strange heat problem

09-08-2008, 06:17 PM
When I turn on the heater not only does it take a few minutes to blow out hot but the vent that blows to the back seat only blows out cold air no matter what. ????????

09-08-2008, 09:39 PM
Are you trying to get heat when you first turn the car on? Because the car does take a little time to warm up and hence give you any heat through the HVAC system. If this isn't the case then you may have a bad heater control valve.

The back seat face vents in the center console only blow cold air. The floor vents under the seats will blow air at the set temperature.

09-11-2008, 09:10 AM
Is the heat delay related to the engine speed? If so, it might be your aux. water pump. Mine went out (on my '95 e34) and the sympton was that I didn't get hot air when idling even if the car was warm. If I revved the engine, or simply starting driving, the air would heat up fast.

Also, +1 on the rear vents. Cold air only out of those. There's a theory on that, related to reducing condensation on the windows, but I never did understand it. Good luck.