I have a small wine frige with bad peltier controller so I was thinking of getting a controller on ebay for $15. Only think is I need to know the voltage of the peltier unit. Do these units use a common voltage or do they differ?

 

A peltier cooler is a current driven device and they are specified to operate with a specified current, along with a voltage. Does your device have a current rating label? Or a voltage label? That is what you need.

 

You may want to look up this thread:

How to repair a thermoelectric wine cooler

 

You may want to look up this thread:

How to repair a thermoelectric wine cooler

That thread gives lots of part numbers and not one word about voltages or currents. Not very useful

 

There is a red and black wire going to the peltier the 2 additional wires. Guess those are a temp control device.

 

You will need to look at the controller and see if it includes the power supply, or not. AND another question is how do you know that the controller is faulty? What are the symptoms? I was asked to repair a mobile peltier cooler a while back and the fault was a broken wire in the power cord. Very easy and cheap to fix.
So please advise us as to the specific complaint, and what you see, investigating the controller.

 

I have a small wine frige with bad peltier controller so I was thinking of getting a controller on ebay for $15. Only think is I need to know the voltage of the peltier unit. Do these units use a common voltage or do they differ?

Usually peltier modules for wine coolers are 12V or 20V, @10A ,. Are there any markings on it ?

 

That thread gives lots of part numbers and not one word about voltages or currents. Not very useful

Literally dozens of people have used this thread to repair their wine cooler. You're right that there is not a lot of detail about the peltier devices and that's because they are rarely the failure point. It's usually the power supply, and specifically a handful of capacitors on the PS board.

Many pelters are designed to draw their max current on a 12V supply. So for instance a peltier will have an apparent 1.2Ω resistance and draw 10A. I've tested this kind by briefly touching the leads to the battery in my garden tractor and feeling for cold on one side and hot on the other. Why briefly? Because without active cooling (the fan), the peltier will rapidly overheat, get hot on both sides, and ultimately destroy itself.