Thread: Airconditioning thermostat - burdon type - fix or replace?

Ok, had a quick 5 minutes and rigged up a heavy wire to jump the compressor. Which burst into life nicely. Cold air out the vents even. So I am either looking at wiring or the thermostat/burdon tube thingo. Hmm. Have some contact cleaner. Will dive in later!

So, popped the glove box out. That godamm thermostat is hidden away! I'm gonna need 4 elbows to undo the Philips screws! And there's no info on the net about what you are supposed to do once you undo them. I'm assuming I'll be able to drop the thermostat into the footwell to work on. But because of the burdon tube into the evaporator, I won't be able to remove it. So will have to take it apart where it is to see if there is any corrosion. What could go wrong?

And a photo to show the bugger hidden up the back. It's the thing with the two Phillips screws on top, behind the green wire.

Has the Thermostat got two wires?
If so get them off and bridge them out,that is join them together and see what happens.

It might save you removing the 'stat for nothing.

I vaguely remember your issue(maybe from your build thread).

Sorry, been busy myself.

But what fuses and relays have you checked.

A/C isn't as simple as just a switch, compressor and thermostat.

There are two other switches to look out for that can halt the operation of the compressor clutch as well.

If you have RAVE, there is a step by step to help you trace power through the system.
The two final steps relate to the clutch cutout switch and the temperature switch on the evaporator.

Doesn't say in any of their step by step to check the thermostat for the HVAC system.

If you want to trace it using RAVEs instructions, you need the electrical library, and start at page 320.

my money is on the clutch cutout switch, on the underside of the thermostat elbow .. looks like a coolant temp switch.

Originally Posted by scarry

Has the Thermostat got two wires?
If so get them off and bridge them out,that is join them together and see what happens.

It might save you removing the 'stat for nothing.

Thanks Scarry. It does have two wires. I undid the screws and pulled it into the footwell. Sprayed some contact cleaner into the body of the thermostat. But no go.

Originally Posted by AK83

I vaguely remember your issue(maybe from your build thread).

Sorry, been busy myself.

But what fuses and relays have you checked.

A/C isn't as simple as just a switch, compressor and thermostat.

There are two other switches to look out for that can halt the operation of the compressor clutch as well.

If you have RAVE, there is a step by step to help you trace power through the system.
The two final steps relate to the clutch cutout switch and the temperature switch on the evaporator.

Doesn't say in any of their step by step to check the thermostat for the HVAC system.

If you want to trace it using RAVEs instructions, you need the electrical library, and start at page 320.

my money is on the clutch cutout switch, on the underside of the thermostat elbow .. looks like a coolant temp switch.

Cheers AK83. My problem is that my copy of rave is on a CD and none of the computers in the house run a CD drive anymore!

So I was relying on the forum and an Aircon guy rather than a procedure. We checked the cutoff switch and gas at his place the other day. Then I checked the relays in the driver's footwell and both fuses in the engine bay. I also checked the compressor by wiring straight to it from the battery and it works.

I'll endevour to try and get hold of a computer with a CD drive so I can check Rave.

Cheers.

Btw - I have a Haynes manual and a 200tdi full workshop manual. Both pretty useless for this one but got me through the head gasket ok.