300guy

1984 Porsche 944 with air-conditioning

The heat is stuck on. Vacuum lines are connected and are functioning working. I replaced the heater valve with one from my parts car. No change – heat still stuck on. I disconnected the heater valve control cable, and manually move the valve to the off position - heat still stuck on.

Question – which way should the arrow on the valve point? (Towards the engine or towards the heater core?

Question – if the valve was installed the incorrect way, will this permanently damage it?

Question – with the valve in your hands, should it be possible to blow some air through it when it is in the closed position?

Thanks,
Colin

BeerBurner

Look here. It may also be your heater clips.

BB.

Jfrahm

Heater clips on an early car?

931guru

The arrow on the valve points to the heater core.

300guy

Thanks 931guru... I'll verify that the valve is installed in the correct orientation.

BeerBurner

Gah! You're right. I knew there was an early "cause" but for some reason assumed it was clips as well.

BB.

sillbeer

This is what mine was: the actual control assembly tab broke off, and was not holding the cable, so when you slid the dial back and forth, you weren't sliding the cable, just moving the whole thing...in this picture it is the farthest cable on the left, you can see theres nothing holding it.

300guy

Thanks for the post Sillbeer! I think that I'll buy a new heater valve, make sure that I install it in the correct direction, and hook the control cable back up. I'll also check out the control assembly in the dash.

sillbeer

before you buy a valve! check to see if the valve is opening and closing!

pcarfan944

I couldn't figure out my heat always on problem and just ended up tieing the heater valve shut with a zip tie. If you dont drive it in the winter, that'd be an easy temp fix for ya.

300guy

I have been using the car with the control cable disconnected and the heater valve manually set in the off position. Heat STILL stuck on. This is why I think that I might need a new valve.

sillbeer

ahh yes..it sounds like you might then

mbonner

Same car, same problem, twice. I now have a choke cable from the glove box to the heater valve. Is it just my car or do all early cars have hot air coming through the firewall with the heater valve off?
Mike

mbonner

Same car, same problem, twice. I now have a choke cable from the glove box to the heater valve. Is it just my car or do all early cars have hot air coming through the firewall with the heater valve off?
Mike

JimGinKC

Hello everyone

just got an 83 944 up and running (new timing belt - the car had been sitting for quite some time), and my heat is stuck on too. Where is the heater control valve? I slide the temperature control and see the cable moving on the drivers side footwell, but I don't know what else to check

Thanks

Jim