Replacement heater valve issues

[Malcolmr]

I'm encouraged by WN's 3.9C and will work towards that. And, Herman, yes, I have done what you suggest on hot days and can survive (just!). Car gets a bit stuffy on recirc though after a while...

[AndyWest41]

Hi all,

Just a bit more information regarding this fault. I had the air con regassed today and although the temperature in the cab does now get lower than before, the valve still does not move. Can someone confirm that when you turn the ignition on, the control valve should rotate (even before starting the engine)? Nothing happens on mine at all. With the engine running, the valve still does not move regardless of what temperature is set on the control unit in the cab.

I am going to try changing the air con ECU with a new unit in case this is the fault. Silly question, but can someone tell me where it is located in the car?!

[Malcolmr]

Yes Andy. It sort of flexes its muscles before settling down to where the ATC thinks it should be. I spent some time fiddling with mine (as I described before) with the valve motor disconnected from the valve, ie with the little white disc taken out. You do have to take the whole Black Olive assembly off the car (but leave the hoses connected) to do this. Then you can watch through the windscreen and see if it turns. You can also test the motor by putting 12v over the two power pins. I'd be doing that before replacing the ATC brain. Also, there might be a fuse in that curcuit somewhere which may have blown if the motor was unable to turn when you first set it up if it was in the wrong position.

[AndyWest41]

Dear all,

Ok, so after a few weekends of fiddling around with the A/C I thought I should report where I am. I went and had the a/c regassed but this made no difference as I feared it wouldn't. I then checked all the seeming appropriate fuses, also to no avail. Finally I cleaned all of the contacts on the plug that connects the motor and refitted everything, but still no luck. So I gave up, set the motor to its 'cold' position and decided I would just put it back to hot in the winter.

During the following week and our depressing weather, I went out in the car on quite a cold day. I didn't change the temperature settings inside the car, but once the engine had warmed up, I suddenly got a blast of nice warm air. This continued until the cab warmed up and then the a/c turned itself down and maintained the temperature! I got home later, removed all the trim (again!) and checked the motor for movement when the ignition was turned on. My key observation was that the motor I have does not move when the ignition is turned on. It only moves when the temperature is changed in the cab with the engine running.

The reason why it didn't move before but now does remains a mystery. I suspect it was something to do with the plug on the motor, but whatever the reason I'm a happy boy again now I can travel in comfort regardless of the temperature outside!

[Malcolmr]

Any result is a good result with our cars Andy! Bit like in an aircraft where any landing you can walk away from is a good landing! Sounds like a bad connection somewhere after all. Fingers crossed everything now keeps working for you!