Basic question on cooling and heat

[savor_savvy]

Based on a basic thermoelectric cooler, which can achieve a temperature of 5 degree celcius the lowest, and when that happens, is there anymore heat around in the cooler? If yes, why and if no, why?

Thanks.

[Jim_H_WY]

I'm not sure I understand the question.

Thermoelectric coolers transport heat from one surface to the other via the charge carriers flowing in the module.

Heat is carried from the "hot" side to the "cold" side, and additional heat arrives at the hot side due to the heat generated within the module from the power it uses.

So more heat must be dissipated on the hot side than just that which has been removed from the cold side.

It's easy enough to calculate how much extra heat you'll have if you know the current through, and voltage across, the module.

Typical thermoelectric modules are only about 5 to 10% efficient, so a lot more of the heat arriving at the hot side is from the power consumed by the module than from heat removed from the cold side.

You have to remove all of that heat with the heat-sink and fan (if used) that's on the hot side.