Weird HVAC issue

[bnvll2000]

Got a weird HVAC issue with air flow. Dual zone controls and when the temperature is set to about 75 or below it will blow fine out all the vents, floor, defrost. As soon as I start to turn it up past that temperature it gradually decreases the air flow to the floor vents. It still blows out the vents and defrost, but not quite as much as when I have the temp lower. If I mix between the floor and vents it somewhat blows out the vents, but almost nothing from floor. I have it manually set for floor at high heat and high fan speed and barely anything comes out. Blower works fine. Doesn't seem to be the evap coil since the lower temp works. I tried all different manual settings and still nothing from floor at high heat. But at 60 it blows like crazy from floor. Any suggestions?

[bogard985]

Sounds like you have a problem with your blend doors. If you look at the thread of "common problems" under HVAC it should describe in detail what is going on and how to fix it

[bogard985]

http://www.pontiacbonnevilleclub.com/fo ... 25362.html

[bnvll2000]

Thanks! I will give it a try. Last winter I was freezing. Got 265000 on this and still running. Get my heat back and I will be set for another 200000!