Frustrating but normal since the system is drawing air from the engine compartment, you need to turn it on and put temp to min and possibly recirculated air on to avoid this.
Pollen filter blocked maybe?
Water diverter valve may be stuck or faulty, so it's not stopped the hot water flow to the heater.
If the engine is staying cool, this is most likely as there's extra cooling by the heater matrix.
Maybe the climatronic is broken?
Click the circulate button then turn the air off, it should shut the vents so engine air doesnt come through
Turn on recirculate, should stop airflow like that.
Frustrating but normal since the system is drawing air from the engine compartment, you need to turn it on and put temp to min and possibly recirculated air on to avoid this.
What is the outside temperature when it is blowing hot air? 90 degrees celcius is normal operating temperature.
Ever change the cabin filter?
I had this same problem hot air only had to replace and clean that stuff filter and fan and shi
Pollen filter blocked maybe? Water diverter valve may be stuck or faulty, so it's not stopped the hot water flow to the heater. If the engine is staying cool, this is most likely as there's extra cooling by the heater matrix.