Opel Vectra Climatizer

Hello everyone:

I have a 2000 Opel Vectra B with climate control. The problem I'm having is that the heater takes a long time to heat up. The car temperature rises as usual, and the cooling fan comes on at its normal operating temperature. I downloaded the workshop manual for this car and saw that the heater valve seems to work with a vacuum valve.

I would appreciate it if someone could explain how it works.

Thanks.