Heating controls- no heating

bombur

Zorg Guru (III)
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British Zeds
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May 8, 2021
Points
139
Location
Porthcawl, Wales
Model of Z
Z3 1.9, Z4 E89 2.3
Ok so I have always had an issue with my heater control. It was sticking at the top pint between cold and heat. Anyway in the summer after I fixed my AC I turned the dial to cold quite vigorously and voila nice smooth control from then on and cold worked lovely. HOWEVER today when I put the heat on....no heat. So I obviously broke something when I turned it against the resistance.
What's it likely to be and what do I need to do to fix it please!
 

Duncodin

Zorg Guru (III)
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Points
139
Location
Pontrhydyrun
Model of Z
Z3 M44
I like checking the simple (ie zero cost) things first.

In the case of no heat I'd make sure there's no air lock in the system.
 

bombur

Zorg Guru (III)
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British Zeds
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May 8, 2021
Points
139
Location
Porthcawl, Wales
Model of Z
Z3 1.9, Z4 E89 2.3
I like checking the simple (ie zero cost) things first.

In the case of no heat I'd make sure there's no air lock in the system.
Its deffo to do with the controls, as was working fine before I put some weight in turning the dial. I never tried the heat after that...til now
 

Duncodin

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139
Location
Pontrhydyrun
Model of Z
Z3 M44
I must confess that I don't know whether the heater control in a Zed is a pull/push cable or whether it's electrikery. If it's cable you'll see the cable moving at the valve under the bonnet as you twiddle the knob on the dash.

But i think its electric and the knob on the dash is acting like a kind of volume control. Find the valve under the hood and get your multimeter. Knob all the way to hot would show zero V at the valve. Knob all the way to cold will be battery V at the valve. If the V doesn't change then the knob is duff, or come loose off the spindle or whatever its called.
 

bombur

Zorg Guru (III)
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British Zeds
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May 8, 2021
Points
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Location
Porthcawl, Wales
Model of Z
Z3 1.9, Z4 E89 2.3
There was always resistance at the central point on the dial and I had to turn though it and bump and then it was ok, the one way. Same if I wanted to go other way. Now its smoothly working but only cold. Think something broke inside.
Will have a look under bonnet
 

bombur

Zorg Guru (III)
Supporter
British Zeds
Joined
May 8, 2021
Points
139
Location
Porthcawl, Wales
Model of Z
Z3 1.9, Z4 E89 2.3
Any idea which side I go into to look at the pin fix, via passenger side? Just noticed @hard top went in via passenger. How easy is it to get the console nearly all way out to do the repair? is it easy to put back?
 
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