The Upgrade woes...

I found the B5k on ebay in various quantities. I bought a 5pack. Search ebay for b5k potentiometer to view the numerous offerings.

You could use any length shaft if you use an extension. Of course, as long as the mounting location and method would accommodate it.. This way you can get your project back together and move on to the next instead of searching endlessly for the exact fit.

There are different approaches to this. Try searching for "potentiometer shaft extender", or "rotary switch extension"

I used them when I rebuilt an old guitar amp last year and found mine on ebay. I ended up epoxying the two shafts together using a copper sleeve.

You would also need to make sure that if there are additional digits in model number that you use that to determine the specs. The specs should match on whichever you are buying.

Have you tried mouser online? If you do have the complete model number then someone there should be able to find a solution that works.

Are these potentiometers dead? If not you could unsolder any wires going to them and with a test meter set to measure resistance (OHMS) rotate the pot through a full back and forth swing starting with it at one end, you will see the resistance either climb or fall. Once you have the maximum resistance figure you can use any potentiometer that has the same characteristics to get the same result.

These guys seem to have a range for sale individually. http://www.jameco.com/1/3/alpha-b5k-potentiometer.

Here is how I usually search for electronic parts.

Specialized search engine: octopart.com
Then buying where I have an account. Many of them sell single items to individuals, the usual suspects (Digi-key, Mouser, newark aka farnell aka element14, RS Components, TME, ...) certainly do.
(Unless you live in Germany, then you often have to be a company or student to deal with them. No commercial register number and tax ID? No business.)

If that does not help Google will usually find something. In case of partial part numbers the picture search can also help to ID parts better.

I also search directly where I buy, local companies and even national chains are not listed on octopart.
Then there is a small company which will source obscure parts in small quantities at acceptable prices.


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The potentiometer is not the full dimmer.
There are more electronics behind it.
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The part is a potentiometer. Buying the same part as direct replacement obviously works. But any replacement which fits the electrical and mechanical requirements will do.

One of the standard marking schemes translates to:
B: linear
5k: 5k Ohm resistance (5000 Ohm)

It has to fit mechanically.
Diameter and length of the shaft are important. Easy to cut down if needed, much harder to add. Also the type of shaft. (Round, flat side, knurled, ...)
Mount type, is most likely panel mount (washer and nut). The diameter is dependent on the shaft and pretty standard but may differ.
Then the electrical connection, probably solder lugs.

Important but not too obvious: Power rating.
The ones linked above are 1/8 to 1/2 watt. Without full part number you can try to deduce this from physical size. If in doubt use the higher rated of the same size. Prices are not that different.

Then there are also additional features like integrated switches. Those are pretty rare but certainly a possibility with dimmers.

Long bushing, that makes things a bit more complex.
That the potentiometer is ganged with a switch does not add much further excitement.

If we ignore the bushing length for a moment, quite possibly:
Alpha (Taiwan) RV24A01F-10-15R1-B5K-3

Should tick most boxes including the markings and layout on the back, BUT the bushing is way too short. (6.5mm)


At that point I would ask myself If I just want to OR of have to replace.
Then I'd think about switching parts around. Usually thats not too hard. Bend open, switch innards, bend closed. If the new innards don't fit go back.

3 of them from mouser.com within the US for ~$11 USPS snail or ~$15 UPS/Fedex, not too bad for an experiment. Start training with the additional new one.
Double check first if yours are really 5k Ohm tough. Where three pins are in a row the two outer ones should read about 5000 Ohm with a multi meter. (+/- 20%)

countersink the back of the cabinet with a hole saw, any length bushing will do

What kind of fridge are you going to replace with existing one with? Are there products out there that will fit in the same opening? I'm thinking that's going to be my next thing that goes as the compressor is sounding a bit loud...

Finding a fridge to fit in the space is a big challenge.

Ruby has recent experience with the fridge dance.

It was a dance I don't want to be reminded of Lou, LOL..