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I bought a Haier wine cellar for $5 that no longer cools below 81 degrees, what would cause that?

I know it's a thermoelectric cooler. When I got it home the inside temp read 101. I left it on for several hours and it went down to 81. But it's set to go down to 46 (there is no lower setting than that) but it won't get cooler than 81 degrees (not even after being on for days). When I removed the back, it looks pretty simple, there is a large fan on top of a large heat sink on the back. From the inside, there is a second large fan that blows into the cooling compartment. I'm trying to figure out how it works so I can either fix it or turn it into something else.

jefftracy3 years ago
This post is a few months old, but what the heck.

There are really on 3 parts to a wine cellar; a fan, peltier chip, and a PCB. There really isn't anything else that can go wrong.

The most likely cause is the PCB. Some of the soldering points on the back of the PCB are done by hand and are done very poorly. What has likely happened is that a wire that leads to either the fan or peltier chip has worked loose which is keeping the unit from cooling. If you are handy with a soldering iron and a multimeter you should be able to figure out what isn't getting electricity resolder the wire.
Yankinoz is clear out wrong. A Peltier cell can shift close to 70C or certainly more than 35 C - that is AFAIR 136 F and 63 F - and still shift significant power.

Of course it will chill wine, it will take it a fair time to do so though, so pre-chilling might be quicker.

Steve
I guess all of the TEC that are produced by Malcor and several other companies need to contact you. If you want to use a "stack" - you can push the temperature variable BUT usually the TECs that most people purchase in the $15 - 20 range are not capable of a 70C range.

I would really like your source for the 136F+ to 63 F- range peltier. It would solve a problem my company has been working on for the last ten years and I would be happy.

If you go to Radio Shack or whomever sells the in car "keep it warm/keep it cool" little fridges you will see that in the instructions that there is a 20 degree range that the TEC work within and they advise you cool or heat your beverage/food prior to putting it the little unit.

Back to the problem at hand:
The main causes of failure of a TEC are too much electricity (the heat sink isn't doing its job) and secondly moisture (causes corrosion and shorts out the peltier).

I have been working with solid-state cooling for 20 years and have a fair bit of experience with making them work and also frying them in many ways. (I like to push the envelope of things) ;)

The key to using a Peltier device is not to shift significant power. It is to use the device in a cyclical state. My company is the only company able to do this. I have built a proprietary controller that allows the user to control the temperature variable and not overload the TEC.

I wish you all the best. Sorry, if this created a bit of controversy. All the best.
Like you, I've been working with Tecs for more than 20 years, in a highly cyclic mode. We routinely move 20 W from -45 to reject at around 40 C, that uses a three stage air cooled design, the high stage is shifting over 250W. We then reheat to +30 and go straight back down. We have never had a cell failure in the field. We are shifting considerably more than 20W in another, single stage design, and moving it across more than 60F, using a nominal 100W cell.

You didn't qualify the statement in yuor answer
"A Peltier device (TEC) under normal circumstances can only cool or heat +20 F above or below ambient."

What you are saying now is that cheap cells, improperly mounted, often don't achieve more than 20F (11C) differential on load.
ThreeWestCreative (author)  steveastrouk3 years ago
"Clear out wrong" is a bit over the top my friend. A minor correction would have been sufficient. I figured there was more to it as the unit can clearly go from room temp to 46 degrees when working. I don't really care how much of a shift it can do. I know the unit is capable of 46 degrees and I was seeking an answer as to why it was no longer capable of doing so. Which 3 of you seemed to provide the key.
When other people look at this question, the answer has to be right, since its for the record.
possum8883 years ago
Sounds like under the heatsink is a Peltier unit, and its broken. Basically, one side gets hot, and the other side gets cold. http://home.howstuffworks.com/refrigerator6.htm

ThreeWestCreative (author)  possum8883 years ago
Thanks for the reply and link! I think you, yankinoz, and steveastrouk are correct. I wasn't sure what made the cellar work. It's also good to know it's designed just for maintaining the wine temp and not to cool it per Se.
YankInOz3 years ago
A Peltier device (TEC) under normal circumstances can only cool or heat +20 F above or below ambient.

That said, it does appear that the TEC is fried. It is not difficult to replace as long as you know how to solder and you make sure that you do it properly. Heat sinks also need to be oriented correctly to heat or cool... it is about the flow of electrons. They work on 12 volts and various amps.

If you want to replace the TEC, you will have a good but not the best wine "cellar". You will need to chill your wines before you put them in the "cellar" because the cellar will not cool them. It is more for keeping the wine cool once you have chilled it OR to maintain a certain temperature.

If you are not good a soldering and do not understand the need to use a VERY good heat sink between the TEC and the + and - leads (or you will fry your TEC - as previously mentioned), get someone who can do it for you. It obviously will be worth it.

If you shop on eBay for a new TEC - do not go cheap. You will regret it. And get one with a higher wattage. I use 180 watt TEC to do a 75 watt job... and I use a controller I built to maintain constant temp without frying my TECs.

If you have any questions, PM me. I will be happy to help. I am on Australia, so be patient with answers. (Usually a day) ;)

Cheers and good luck.
orksecurity3 years ago
Guess that's why they only charged you $5...
Yep.
The peltier is probably broken. You can replace that from stuff onEbay for not many dollars.
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