In college my physics professor showed us a thermoelectric couple powering a fan. He also explained how if you apply a current it cools one side and heats the other side. I have been working on a cooler that uses a TEC to cool the inside (see my posts Considerations for solar powered thermoelectric cooler with fan and 12V fan does not work when in parallel but does in series) but something is wrong. When I give power to the TEC in the correct direction, one side gets so hot I burned myself, but the other side was getting warm. Why is this side not getting cool?
In a sense it is working, by keeping one side cooler than the other.
The problem is that you're not removing the heat from the hot side fast enough, so it's not getting colder than ambient on the cool side. If you allow it to get too hot you'll damage it.
You need a BIG heatsink on the hot side for it to work. TECs are very inefficient, and you need to remove all the heat from the cool side, plus all the wasted heat you're pumping into it (which is much greater).