Heat from AC vents on initial on

[phildg2000]

Hi all!

The saga continues with my brother-in-law's 89 525i. I noticed something about the AC this afternoon. I drive the car around until the engine has warmed up and then i shut it down. After a few minutes, I start her up again (engine still warm) and I turn on the AC and hot air comes out of the vants for about 20 seconds and then it starts to cool. What's happening here? How do I fix it?

Thanks,
Philip

[Dan in NZ]

That's normal. When the heater valves have no power to them (car off), they open, allowing a bit of hot coolant to flow through the heater core. Just get used to it.

[phildg2000]

That's normal. When the heater valves have no power to them (car off), they open, allowing a bit of hot coolant to flow through the heater core. Just get used to it.

Thanks Dan. Ok then; I just thought that the AC might be working overtime to overcome the heat. Come to think of it, my old Mercedes 190e did this too.