This is the first time I have tried a Peltier cooler and I am disappointed. I put a sheet of aluminium on the hot side and powered it up. The cold side cooled down. A bit. I've measured it at roughly 10 degrees C below ambient. I had hoped it would freeze a few drops of water but it gets no where near. The hot side on the other hand can get quite hot.
Now I know my cooling is crude and my testing is crude but I thought they would perform better than they do. Is it worth me carrying on with better cooling or is this typical of a Peltier cooler? Is there a better one that the one I've tried?
Hi,
Put a black finned aluminium heatsink on the hot side, be carefull not to overheat the device as that deceases is efficiency and life.
The Amazooom link doesn't tell you all the story.
I just did a google 100W peltier diy
and it came up with some results that might be worth checking out, some YouTube stuff specific to your device.
Tom.....
PS, Its great when I can use my faceybook emoji's here.. goody goody...
A 100 watt Peltier means you have to get rid of 100 watts of heat BEFORE you can get rid of heat from the cold side of the Peltier. That means a very large heat sink and a fan to move the warm air. Peltier devices that freeze water usually use a heat sink with water cooling. Look at the description of how A Peltier device operates and you will see how much below the ambient air temperature you can get.
Paul
I certainly have not put anything like 100W into it. I was hoping that with, maybe, 5W and a sheet of aluminium on the hot side I'd at least get a bit of frost on the cold side.
How did you limit the wattage? Remember, there are a whole bunch of diodes in series so the heat from those diode junctions must be dissipated somehow.
Paul
I have a variable power supply with a voltmeter and ammeter. I turned the voltage up slowly while watching the voltage and current until their product was roughly 5.
The cooling efficiency of a Peltier device is 10-15%, and you MUST effectively remove the heat from the hot side.
So, given good hot-side heat dissipation, 5W power input results in less than 1W cooling, i.e. less than 1 Joule/second heat remove from the cold side, and more than 4 J/s added to the hot side.
Temperature change stops when a given hot side to cold side temperature differential is reached, so every reduction of the hot side temp translates to that much reduction of cold side temp.
Most Peltier devices will be destroyed if the temperature anywhere inside goes much above 80 degrees C. For higher temperatures, you need TG (thermal generator) grade devices, which use high temperature solder on the junctions.
Thanks jremington, that's the sort of information I was hoping for.
Jiggy-Ninja well, I didn't really know what to expect, I posted here to get an idea of what was reasonable. Now I know that what I am getting is as expected.
Here is my 80 Watt cold plate setup, based on a CPU cooler. The "cold output" plate is on the right, and when in use is attached to a larger plate. The cold side runs at about -20 C in the open.
Thanks for jremington.
I found a CPU cooler and stuck the Peltier cooler to it, you can see ice in the middle.
To do that I am putting about 30W into the Peltier cooler.
Don’t forget it’s about heat not temperature , more current gives more heat movement -
So if it can move a little heat with a small temperature difference it will - if the cold side is contained in a insulated box , the temperature will continue to fall as the heat is removed from the box .
The night was cool the......... title of an old song.
Seriously this is a neat bit of information. A clear night sky looks like -40°C. This is why sitting under a patio umbrella on a clear night seems warmer that being under the sky.
My very first Arduino project was converting a portable food/beverage cooler/warmer which used a 12 volt Peltier device. I needed a way to store solder paste in cold and then warm it ready to use based on a time clock/date. So, look for something like a portable cooler on Ebay, etc. That is where I got mine. Worked for several weeks, then cheap relays began to give out, etc.
Paul
Hi Perry. I've got a peltier controlled butter keeper on my bench, it keeps butter around 20 degrees while the room temperature varies +/- 10 degrees around that. The butter is in an insulated box, and there is a large heatsink and fan on the outside. Peltiers are not very efficient so there is a lot of waste heat to move along with the load heat. Here is a useful link Tellurex Peltier FAQ
BTW thanks for your tutorial on using the Nextion displays. I have a project on the board to use one to drive a butter keeper.
