Topic: my heater stays on all the time

[Butterwolf]

I sure hope that I don't have to tear into the dash and replace my climate control system controls. Please tell me it's just a vacuum line issue. I didn't see a search box to search the Forum and I apologize ahead of time if you're having to answer this question for the 35th time. Thanks for your help.
Butterwolf y88

[RENOVATIONS]

Do you mean the fan runs on a low speed at all times?
If so, that is normal and a built-in safety feature...intended to keep the cabin clear of  exhaust fumes.

Also there is a search feature at the very top of the page if you need it in the future.

[Butterwolf]

Thanks for the quick reply. No I mean it is blowing full hot all the time. I'll look again for the search box. Thanks for the heads up.

[Stringer]

If it is blowing hot all the time the blend door is probably stuck open.  This door blocks off the heater core. When the door is open (even partway) air is allowed to pass from the heater core to the vent and/or ac air.....thus allowing you to control the temperature. The door has a plastic mount for the hing.  You can replace it but the pin is difficult to get out. You just need to remove the main A/C duct on the passenger side.

https://www.classicindustries.com/shop/1979/pontiac/firebird/parts/?q=g9223

[Wallington]

There is no off for the heater on these, just a redivert. As Stringer said, often the plastic retainer breaks off the heater box door which leaves it open to enter dash vents. Does it feel like the heater control cable is opening and closing anything, attached or just loose? You'd be able to hear it and feel it.