I have a 1986 Vanden Plas that only blows hot air, no A/C, even when it's just supposed to be blowing ambient air. I imagine that the A/C pump is shot but looking for other ideas and guidance.
Thanks.

 

The heater valve might be stuck open.

The valve is on the firewall, almost dead center behind the engine. Check the vacuum hose. No vacuum = open heater valve.

If the hose is OK, have a help slowly operate the temp control knob while you observe the heater valve. You can tell if it's operational because it has an external operating lever.

Sometimes they just seize up and, with luck and some aerosol penetrating spray, you can manually operate the lever and bring 'em back to life.

There are many other possibilites but the heater valve is an easy place to start.

When you operate the temp control knob to you hear a faint whirring noise and the sound of the air control flaps moving? If so, the system is at least trying to obey commands, so to speak.

When full cold is asked for the air should come out of the center dash vent. Does it? If so, that's a good sign.

Cheers
DD

 

Hello,

A few of us are having this problem right now. I've received a lot of help through my post "Having a difficult time finding AC amplifier".

Did you just get this vehicle? Did you see the system working at one point?

In my case, I bought the car a year back and the HVAC didn't work, so I didn't know what I was aiming for (ie, what should move, what sound things should make, etc.).

Anyway, give some details about what works and what doesn't, read my thread where Doug and other members helped me with some good troubleshooting advice.

If I ever get my system right, I'll post a global recap with pictures etc to help the next guy.

ROD

 

Yep, saw the other thread posting which prompted me to ask. I haven't physically had the car for about a year as I dropped it off at a local Jaguar expert to get an initial assessment and some work done that I didn't want to get into. I don't have much space to work on anything at home.
But these were issues my parent's dealt with. As for hoe long ago it worked, don't know. I do believe that the place where it was worked on before didn't do what they were paid for, based on recurring problems over the years for the same issue.
When I have more info I'll post on it. Right now getting ideas for where to look to start running down the car's issues.
Thanks!