Aircon / Heater zone selector switch not working

[crowee]

The selector for the zone control for the heater does not work. The selector turns but the aircon heat stays directed at the demist outlet on the window. It is a 1997 VT Commodore Wagon Series 1. Any advice on how to fix this problem appreciated or should I just take the car and a mortgage application to a holden dealer

[BlackVXGTS]

There are two vacuum hoses that connect to a vacuum tank which is located on the passenger side of the HVAC (heating, ventilation, air conditioning) unit. One of these may have come loose. You may be able to access them by removing the glove box interior.

[crowee]

Thanks I will check that out

[jetboy]

Also check the vacuum hose on the back of the plenum chamber and the little round vacuum ball front driver side wheel well in front of the tyre ( in behind the gaurd liner ) an all hoses running to an from . An yep removeing the glove box reveals all

[crowee]

I have checked in behind the radio and found two small pistons which when moved manually shifted the airflows to each of the different zones but I could not find any vacuum hoses that appeared to be loose or have come off. Leading from the back of the switch were four wires two of each which went to the two piston type devices. Can someone tell me if I am in the ball park. And also how do you get to the vacuum tank is it neccesary to pull the whole dash off. Finally what is a Plenum chamber. Sorry for my ignorance but I was a champion at fixing my old HR.

[crowee]

I have rechecked it and have only found the one vacuum hose that runs of the heater through the floor should there be another if so where do I need to look.

[crowee]

I am feeling very frustrated at the moment

[TZB]

Hi Crowee. Did you ever get to the bottom of this? My missues VT has the exact same problem.

[crowee]

Yeah in the end I gave up and took it to the dealer service centre. It was pretty much as everyone said a leak in the vacuum hose which they replaced and it has worked fine ever since. Crowee

[lion_g]

how much did it cost?

[Apprentice]

AHHHH I wish this thread had pics and a result.... I have the exact same issue on my VT SS.