I'm new to the forum, and I'm not an engineer so I guess this will seem like a very basic and silly question. But I can't find an answer anywhere else, so I'd be extremely grateful if you would consider my question. I have a Coleman thermoelectric (TE) cooler that doesn't seem to be getting things as cold as it once did. I've cleaned all the fins and the fan motor area of all dust, and I've run the unit for about 15 minutes in the "heat" cycle to ensure there is nothing frozen that would affect it. The fan motor is working great and there is a clear flow of air. But even after cleaning it all out and making sure nothing is frozen, I then placed pre-chilled beverages in the cooler and let the cool down for about 3 hours. Normally, by that time, the beverages would be as cold as when I placed them in the cooler, or often times they're even colder. However, I recently used the cooler for about a week while on a trip, and now I've tried using it in my office at home and it just doesn't seem to be getting as cold as it used to. So, with ALL that said, my question is: Do TE coolers last forever, or does their effectiveness "fade" with age? Thanks for your help!