How to find hot side from a peltier element?

hi how to find hot side and cold side from a peltier element?

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Put power in,
note polarity, Red is positive, Black is negative.
Note which side gets hot,
note which side gets cold.
Write it down.
Job done.
Attach power place hand on device - Say ouch - You found the hot side.

PS is your hand is stuck you found the cold side.
I understand steveastrok. If you buy a peltier cell and then you apply voltage without using heat disipators, BOTH SIDES GET WARM/HOT quickly, so you can't tell which is the hot side.

Honesttly frollard, ironic comments doesn't help in this community.

No, not if you are careful, and quick.

I have used Peltier cells in scientific applications for 25 years or more,


Levity in science is like a wave riding a gigacycle in a magnetic field.

As far as I know the cell gets warm on one side and cooler on the other with an efficiency of around 5 - 10%.

You shouldn't need to heat sink the cooling side to get it to work.
Oops missed that stage..
I like's like the weather reporting rope.
Got one of those it's 100 correct! More than you can say for the weather Office
sandy.12345 (author)  steveastrouk5 years ago
when applying voltage to the peltier it should be attached with the heat sink otherwise it will be damaged
Not if you do it quickly. A few seconds is fine. They are only damaged if the elements reach over 150 C, which can take many seconds.
PaulA1281 year ago

The vast majority of TECs have an ID printed on their heated side.