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Fan on my wine fridge is buzzing, so I'm replacing it with a CPU or case fan off newegg.

Should the replacement fan be rated at more than .13A, or less? I suppose the fridge probably puts less than .13A in, but the replacement fan should have a max of at least .13A. Would it be bad to get a fan with an even higher max, say .15A or .2A?

Edit: Existing fan specs are as follows (from this pdf) and the sticker on the fan.

Model:             RDL8020S
Bearing System:    Sleeve
Rated Voltage:     12VDC
Operation Voltage: 6~13.8
Rated Current:     0.13A
Rated Speed:       2,500 RPM
Air Flow:          27.6 CFM
Air Pressure:      1.7 mmH2O
Noise Level:       30 dBA
Dimensions:        80mm x 80mm x 20mm

I found several fans that have lower amperage, but I'm reluctant to buy them. Finally I found this fan which has .13A rating, but I suppose that means it would always be spinning at its highest setting.

P.S. I realize that almost all computer fans have 3 pins not the 2 that this one has. I figure I'll just splice red to red, black to black, and snip off the yellow one, which is just throttle control anyway.

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    \$\begingroup\$ For starters...is the existing fan 12V DC? Because if you hook a computer case fan up to 120 or 240V AC, bad things happen \$\endgroup\$ – Grant Feb 7 '15 at 19:23
  • \$\begingroup\$ Yes. I'll edit the question to put in the existing fan specs. \$\endgroup\$ – brentonstrine Feb 7 '15 at 19:26
  • \$\begingroup\$ @brentonstrine Put WD40 under the sticker. It should stop buzzing. Example hardwaretexpert.files.wordpress.com/2011/01/computercasefan.jpg \$\endgroup\$ – Triak Feb 7 '15 at 20:26
  • \$\begingroup\$ WD40 is not a lubricant. I know because I made that mistake. WD40 stopped the buzzing temporarily, but then it came back with a vengeance. I tried again today with mineral oil, but it's clear that I need to use the proper oil. A new fan is cheaper than buying the proper oil. \$\endgroup\$ – brentonstrine Feb 7 '15 at 21:35
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Because your fridge uses a 12V fan, I'm assuming that it uses a thermo-electric cooler (Peltier cells) rather than a compressor like a larger fridge would use?

If so, the actual fan current is probably of no consequence. The thermo-electric cooler requires significant current at 12V and the power supply most likely wouldn't know about or care if your replacement fan consumes more or less current than the original.

Suggestion: look for the quietest fan you can find. Don't worry about how much current it consumes - just make sure that it runs from 12V.

I've recently had to replace the fans (both in power supply and on top of CPU) in a couple of professional hard-disk of multi-track audio recorder decks and it is absolutely amazing how quiet some of the new fans can be while still moving significant amounts of air. There was nothing wrong with the stock fans other than that they were far too noisy to be used in the control room where they were situated. The new fans were chosen to have at least the same amount of CFM as the originals but with significantly less noise. The difference was impressive.

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  • \$\begingroup\$ I don't understand. If I buy a fan that is rated at a max of .05A, couldn't it risk being burned out if the fridge is trying to do .13? Also, this fan is inside the fridge and is blowing air over a heat sink that is cold. There is also a fan on the outside, but that one is still good. \$\endgroup\$ – brentonstrine Feb 7 '15 at 20:00
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    \$\begingroup\$ The fan will draw as much current as it is rated (at the given voltage), but not more. \$\endgroup\$ – Roland Mieslinger Feb 7 '15 at 20:06
  • \$\begingroup\$ Ah, and is the converse true: if provided less amperage than it's rated for, it will still work but just at a lesser power draw? \$\endgroup\$ – brentonstrine Feb 7 '15 at 20:13
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    \$\begingroup\$ Yes, but probably also at lower air flow and/or pressure. \$\endgroup\$ – Roland Mieslinger Feb 7 '15 at 20:34
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"Air Flow" and "Air Pressure" are the interesting parameters. The new fan should have similar, or higher values, at the same or a lower current.

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  • \$\begingroup\$ Air pressure information is not available on newegg--if I find one with a equal or higher CFM, that should be enough, right? \$\endgroup\$ – brentonstrine Feb 7 '15 at 20:03
  • \$\begingroup\$ The problem is that "air flow" and "air pressure" are closely related.Think about blowing air through a thick and thin straw. \$\endgroup\$ – Roland Mieslinger Feb 7 '15 at 20:10
  • \$\begingroup\$ Hm. I don't really understand the mmH2O rating. But I'm using it in a situation similar to the intended use as a PC case fan--the only difference is that this is an air-tight system (inside the fridge). \$\endgroup\$ – brentonstrine Feb 7 '15 at 20:17
  • \$\begingroup\$ mmH20, means milimeter water column, which is a pressure. \$\endgroup\$ – Roland Mieslinger Feb 7 '15 at 20:19
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I recently replaced the fan in a small peltier water cooler, and I can tell you something unexpected:

Even if you buy the lowest speed fan you can find, it'll probably be much too fast, and make too much noise. You don't want a jet engine in your kitchen, and a fan that size can make quite a racket. The original manufacturer chose a low speed low flow fan to keep it quiet, but you won't find that in the average supplier.

So when you get the fan, 1) choose the slowest 12V ball bearing fan you can find, 2) buy a range of 5 watt resistors, from say 10 ohms to 200 ohms, just in case you need to slow down the fan, and 3) test it for performance and for noise, on a quiet evening, before you close up the case and fill it with wine.

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