Warm air not blowing through main vents?

[vprelovac]

I have this issue and my service guy was showing me some diagrams that when heating is turned on (ie. you set max temperature) the air con does not blow the hot air through main vents but only the windshield and leg vents. Is this really so? Cold air runs fine through all vents.

[Puglife]

does engine temp get high????
could be an arlock in the coolant system?

[vprelovac]

Engine is running normally, around 90 degrees. When I turn on aircon with lowest temp everything is OK. As I increase the temperature, pressure on main vents starts to drop until all air stops from blowing when I reach maximum temperature. Hot air still runs though windshield vent. So is this design feature or a bug?

[jade]

I have problems with my climate control it works on high or low And you have to start it in high or low if you start it with a temp setting the vents close and if you set it to hi or low after the vent remain closed it needs to be stopped and started in low or hi to work with vents open , electronic problem
Jade