Cobbs

I have an early 944 with the 924 style dash and am having some problems with my HVAC. My car is constantly blowing a steady stream of warm air through the dash vents and on long trips my right foot gets cooked by a stream of hot air. This wasn't a big deal when I lived in So CAL but now that I'm in Missouri its killing me. Also my AC is out and I dont even know where to begin. I would like to remove the dash to see if the hot air is a mechanical issue. and to just see what else is back there. Can anyone point me to a webpage or somthing that tells how to remove the dash and HVAC. Any other suggestions would be appreciated. Thanks in advance.

924RACR

Actually, the first thing that comes to mind is a bad heater control valve, which is allowing coolant through (rather than completely shutting off) and continuing to provide internal heat. Had this on my old '77.5 924.

There is a procedure in the 924.org Tech section for dash removal, but I think your main problem is in the heater control valve, which is underhood of course.

Cobbs

Very helpful lead...Thanks



Next question, Where is the heater control valve? Can't find it in the Haynes manual for the 944.



Thanks again

poobear924

OK - Heater control valve.. never worked on a 944 however on the 924 it is located in the middle of the firewall, perhaps 40cm down from the lip that the bonnet sits on. Mine is black and has heater hose on both sides (heater hose is just like radiator hose, most telling point is that it will have a pull wire attached to it which connects to the lever.
A/C - probably low on gas, check to see if your compresor clutch is engaging and if not find the condensor (I think - the part with the view hole on top of it) and short out the two wires connected to it.. this is a low pressure cut out switch, if your compressor comes in all you'll need to do is regass ... don't run compressor for an extended time with the wires shorted or you'll burn out your compressor.
Lastly dash removal.. two bolts under ashtray, two screws in upper most corners near oil pressure and alternator. two bolts behind heater and fan panel (just pop off with screwdriver). Also two bolts near the footwells connecting to the drive shaft cover.

Cobbs

Hey everybody,
Thanks again for the pointers, I think I've found the heater control valve but on the 944 it appears to be vacuum operated. I'm gonna check that out. Will work on the AC next. Thanks again for the help.

Adrian

Dear Cobbs,
There is a vacuum line to the heater valve. I had exactly the same problem on my 1985.5 944. The vacuum line was disconnected. I hooked it all back up and bingo, for about a week and then the heater control valve decided to fail permanantly.
You have three things to look at. The heater valve, the vacuum regulator or the lines.
When you say that the aircon is not working what do you actually mean. Compressor not running, not cooling, cooling but not getting cold. The heater control valve stuck in the full hot position is going to affect the aircon somewhat. May even be inhibiting the aircon from switching on,
Good luck and by the way, the Haynes manual is useless. I have one as well. I use it to sit on when the ground is cold,
Ciao,
Adrian
911C4
944

Cobbs

I hope you dont think I am a rock but the thing that I was looking at turned out to be the control valve and shutoff valve on the corner where the firewall meets with the drivers side fender. I still dont know where the heater control valve is located on the 944 or even what it looks like. I guess my big problem is just finding the thing. I am baffled how the vacuum system works on this car or any car for that matter and will probably go through and try and find a problem there. As far as the AC goes I found a mysterious "AC condenser fan" fuse blown so I replaced that. I noticed now both fans blow on the car even if the AC is turned off. ??????? The HVAC fan blows hard but its not cool. I know its low on freon but I don't know if somthing else is broken and am not sure how to check. Once again thanks everybody for the help.