They pretty much move all the heat thats in them to one side, leaving the other super cold. There is a maximum difference of temp between the two sides, so cooling the hot side with a heatsink is essential to getting the cold side colder. Running for just a few minutes w/o a fan, the heatsink can become hard to pick up because of the heat.
I'm not sure what temp will kill the TECs but if it's getting that hot in the first place it won't be able to cool that well so you'll know to turn it off and cool it down.
Also, I plan to get some thermal paste after school and that should help my TECs push a little harder. So far it seems that my smaller (30x30mm) TECs are running cooler then my larger (40x40mm) TECs. I'm guessing this is due to the amount of heat it is dispersing onto my heatsink that is preventing it from working as hard. This is another instance where I think a bit of thermal paste will eb helping me out.
you need to pot your tec, coat the side with silicone, if you get water in there they'll die. it's especially important if you are goint to go subzero since the cold side will get condensation and after a while you'll gt corrosion in there you can't get out or clean.
Hehe, yep, if you plan on using a TEC for cooling, a heatsink is 110% mandatory. Deferring to the lovely "all processes are inefficient", if you don't have something to draw away the extra heat produced by a TEC, you're only going in one direction - hotter. Without a heatsinking, you'll eventually have a hot side, and a VERY hot side.
I have never been able to get my TEC that cold, hmmm, maybe I need to start using a heatsink, or up the voltage.
DON'T up the voltage too much. That will kill it. (kind of).
It's the current you need to crank up, I don't know what wattage peltier you've got, but if it's 200W say, it will easily (and happlily) eat 20 amps DC.
Also, if you can get your head round this, then you can do anything with TEC's! The cooler the hot side, the cooler the cool side
I'm sure there must be a better way to phrase that!
I used a couple of pelts in my school tech project, It was a drinks cooler / heater. It went on to win 1st prize in the UK national desgin competition
Usually, you'll get about 67 deg C temp difference from one side to another. I have some current/temp graphs around somewhere. PM me if you're interested.