AC Temp pot issues

My 2208 needs a new pot for the AC temp setting (mounted on the driver door panel). I have been in contact with David Cope at SPF LLC who has been very helpful, but the message from the factory is "pot no longer available, solution is a brand new panel with three new pots and the 2 switches, 1000 USD"
Any ideas anyone?
Rgds
LW
 
If it's only the temp control can that be repaired by an electrical firm? Isn't that just a rheostat? Or a similar rheostat to replace it?
 
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Dave!

Yes, it is maybe a possibility. The pot actually seems to function like a small step generator or something of that sort. Twisting the pot does probably together with some components (IC etc) on the small PCB that is built into the pot casing create pulses to servo motors operating the ventilation valves (I think!). So it is more complex than one might think.
 
Rick!
Unfortunately not. Nothing, only a manufacturing date.
The pot is mounted on a small PCB with other components and then placed in a square plastic casing,
 
Ask SPF if they can supply you with a schematic. That should tell you the specs for the pot i.e. its resistance.

How easy would it be to remove the pot from the board? Normally what breaks is the wiper (center connector) if that's the case remove the pot from the board and measure the resistance a crossed the two outside posts. Then it's just a matter of finding a replacement.

Can you post a picture of the bottom of the board and the pot? If there is nothing else connected to the pot on the board then you can measure it's resistance without having to remove it. You will also need to disconnect the board from the car as any attached load may affect the measurement. If you get this far measure the resistance from each end terminal and the center (wiper) while twisting the shaft. If the resistance changes then your problem may be elsewhere. This should not be to hard and won't cost you $1000.

Some info on pots.

https://www.ibiblio.org/kuphaldt/electricCircuits/Exper/EXP_3.html#xtocid113036
 
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Thanks guys for swift responses. Yes, I think I will have to dismantle the unit, and remove the pot from the PCB for further testing. The obvious fault is that the pot should have clear min and max end stops, as it is now it is limitless in both directions. Lets see, nice to have the AC running even in Sweden, there are normally 3-4 weeks a year with 25-32 degrees centigrade anyhow:)
 
I got this today when I visited Olthoffs....
All three pots are the same. All have the same stamping. Do these match your car? These are off one of the first SPF GT40s P2024....one of my cars. If it is a match I'll send you one to replace yours. You determine the cost. I know I'm way under $1000 for the whole unit you were quoted.
PM if you need too...I hope this helps.
Grady
 

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Those are indeed the original style pots. They have been replaced with a newer style. I will see what I can learn about them during the week. Would be interested to learn by car number where new switch was used. Back of switch is green on new switches I believe.
 
Are the connectors the same between the old and new? I'm assuming they are as they will sell you the "new" $1000 panel to replace the old one. If that's the case why can't they sell you just one new style pot? OK call me unreasonable I'm like that.
 
Richard!
The statement from the factory was "we have made an inhouse replacement for the switch, but that is bigger and will not fit" hence the new panel.
I assume they mean that the mounting holes are not the same.
I think your comments are very valid. I think it would have been wise by the factory to have gone for a main stream solution in the first place, would have made it easier for all. But lets see, maybe an identical replacement can be found, otherwise I will have to disect the one I have and try to replace the broken components in it.
 
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