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Heater problems

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I am having problems with my heater, it hasn't been working right for a while, when the controls are set to hot, the air is lukewarm. It became faulty on a trip up from England when halfway up the road the heater suddenly stopped working correctly.

I have checked the vacuum side and all the flaps appear to be working and directing air as they should. I have backflushed the heater matrix with a garden hose and there was no real amount of crap that came out of it.

I have checked the cable operation at the rotary control and that looks to have the full range of movement. I have removed the fusebox and through the aperture I can see that the water valve lever appears to have the full range of movement from hot to cold.

My next step is to try and remove the valve to see if it is working through it's full range of movement, according to the manual there is a fixing at the top of the pedal box which I can neither see or feel. Can't see it through the fusebox aperture and can't feel it from the footwell.

The manual says there is a temperature sensor on the output of the matrix which "amends the valve opening" relative to the output temp of the matrix, I'm thinking that although I have full movement of the cable to the valve, the thermostatic gubbins is somehow interfering with the valve opening fully.

Has anyone removed this valve before, would it be helpful to remove the instrument binnacle?

Thanks in advance


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...Bottom of a glass method aye?

I have used this method many times to help decifer the complicated and intricate workings of the Esprit.

Sometimes it works and sometimes it doesnt, but in the event it doesnt, just change beer :dizzy:


"Laugh" and the world laughs with you - "Cry" and you just wet your face...

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Try bacK flushing the heater matrix, the sediment in the cooling system likes to gather at the matrix, mine needs back flushing every couple of years, same symptoms as you have experienced, worth a try as its a lot easier than removing the valve (from experience).

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Please do a picture diary of this- I keep dreading it on mine.


Me too. Mine won't go completely cold now no matter how far you move the knob to the cold position. Any pic's or dismantling info would be greatly appreciated. BTW it's not that difficult to get the binnacle off, just four long bolts under the dash which can be seen from the top if you peer under the binnacle itself. Just be careful when you lift it up as you can bash the windscreen with the air vent on the top of the binnacle, so best to put something soft on top of it first.

Good luck hope you find a solution soon.

Martyn :D

Edited by martynv
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Thanks for all your replies, it's taken a turn for the worse.

Binnacle came off no sweat in about 20 minutes. Eventually managed to loosen the water valve securing nut (8mm), I used a 1/4" drive ratchet with 12" extension. The nut can be accessed (pay attention) by passing the socket between the clutch pedal and the steering column, you won't be able to see it. Have drained heater by disconnecting the pipes under the front of the car.

Once that was off, I could tilt the valve and see that when the lever is pulled to fully hot only in the last bit of movement is the movement being transfered to the actual valve. I think that is what I am looking at, it's difficult to see as I still don't have the valve out. Can't get screw out securing capillary bulb and can't pull pipes off valve. I am working in the hole that is left when the binnacle is removed, although I can only get my forearms halfway in.

Have decided to take interior trim off as I have a few jobs to do under there (replace aerial, colour leather, renew front speedo cable, fix squeaks, tidy cables, re run speaker cables, fit new front speakers). Some of the stuff I've had for a couple of years so I guess it's time to bite the bullet and strip the fascia out. So I'll not be finished by Friday.


Photos to follow.

Edited by Nigel
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