Pistol Pete

I've had my car since August and never quite understood the way the heat/ac works. The sliders don't seem to change the volume of air coming from the top or bottom and the fan control does very little. A significant amount of air still comes out when the fan is set to zero. When the AC is on, I get periodic blasts of HOT air for several minutes at a time. Have had no issues with the heater this winter other than the difficulty controlling where the air comes from and how much comes out. What's the deal with the climate controls? Are they just difficult in these cars? By the way, it's a N/A 87' 944.

Vjgtrybno1

Do a search for heater clips - you might just be lucky enough to be able to solve your problem for a few dollars at worst. You will get air circulating with fan at zero, that's normal.

959Lover

And that is why I do not own a 944....

Clint's 944

Check the servo's by the heater clip. Move the sliders while watching them and see if they are moving.

Vjgtrybno1

There are lots of reasons I don't own a 959 - most of them green!

rollis

You are lucky if it is the heater clip but I don't think it is. When the clip breaks, the rod falls by gravity letting only heat pass by. Take the plastic cover off under the steering column so you can see if the actuators are moving the rods back and forth. I had this same problem and I replaced the CCU because my actuators did not move. It was an easy 10 minute fix

rollis

Here's a pic of the actuators to help clarify what you are looking at.

tifosiman

Why, because of the heater control unit or the mode of failure? I would opine that the 944 heater controls are easier to use than many other of Porsches cars from that vintage and earlier. When heating system does fail it is usually one of two issues. If it is the HCU and not the clip, there is an abundance of used parts available out there so the fix is not prohibitively expensive. At least there are no rusted out heat exchangers to worry about.

Ebby_951S

since we're on the topic, i've noticed that on really hot days, my A/C works better when i don't use the recirculate button. in all the other cars i've owned, the opposite is true. What gives?

AndyK

I still can't figure out what the slider position does with the top one to the left, and bottom one to the right? All over to the right is for heat / bottom, right??

Techno Duck

Top to the right puts the air flow to the top vents ontop of the dash, if you close the center vent you get max flow to the dash vents for defrost.

Top to the left and the bottom to the right and you get heat to the floor.

I cant remember, but if you hit the defrost button it automatically does this and defrosts the windshield in a few seconds (due to the incredible heat the 944 has). But this makes a huge amount of noise from the blower being on 4. I think the blower on 4 makes more noise than the engine.

One thing i never figured out in the time i owned it was how the controls work on a early 944 / 924S interior. I have my friends early 944 dash taken out right now and took a good look at the heater control cables, i think i figured it out. The top left control does the same as the topmost control on later cars and the top right controls flow to the floor.

AndyK

Uh....what does bottom to the LEFT do?

Dave951M

I doubt this is the cheapo clip. It sounds more like the HCU is toast.

Pistol Pete

Heat is plenty hot and comfortable and the AC mostly works, excepting when the blasts of hot air come through. It seems like I have two issues, one relating to air direction and one to temperature.