Refrigerator Not Cooling ....

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Refrigerator Not Cooling ....

Postby vja4Him on July 9th, 2013, 4:07 pm 

My roommate tells me that he is a refrigerator expert, and the reason my refrigerators on the patio are not cooling properly is because they are plugged in with an extension cord.

Is there any truth to this? He says the refrigerators are not getting enough power, and will not get cold enough, because they need to plugged into a wall socket.

The patio has a solid roof, and the sides are covered with tarps, so the refrigerators are not exposed to the sun.

We have three refrigerators on the patio: 1) 4.7 cubic feet, 2) 14 cubic feet, 3) 21 cubic feet. The big one is the main problem, and has not been working properly ever since I got it over a year ago (from Craig's List). In the cold weather it will get colder, down to around 40 Degrees F. (4 Degrees C.) when the outside temperature is in the low 20s F. (-7 to -5 Degrees C.). But in the hot weather, it gets up to 70 Degrees F. (21 Degrees C.). The freezer compartment will freeze, but it takes several days or even a week for some items to freeze completely). This fridge has a large computer board that looks like the mother board of a computer.

The medium-sized fridge (14 cubic feet) works pretty good. During the summer I put a few one-quart bottles of ice, which I change out once a week, so it's working ok. The freezer works just fine, and the fridge temperatures maintain an average of around 35 Degrees F. (2 Degrees C.) During the winter, this fridge works perfect!!!

The small fridge, 4.7 cubic feet, is working perfect, and has been for years.
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Re: Refrigerator Not Cooling ....

Postby Watson on July 9th, 2013, 5:11 pm 

I was told using a smaller gauge cord than the equipment requires is like trying to breath through a straw. You can do it, but it is a lot more work, and you will probably die eventually.
So I think the gauge of cord and length could have an effect on the operation of a compressor. I would think you need a 14 gauge cord.

Maybe Dave will give you more of an expert opinion.
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Re: Refrigerator Not Cooling ....

Postby Dave_Oblad on July 9th, 2013, 5:36 pm 

Hello vga4Him,

What is the extension cord rated for? Is it or does it get hot anyplace on it? Ever? If it or any end of it gets hot, then it may be underated. These devices, when semi-idle do not draw much power.. but when the compressor kicks in.. it draws a lot of power. If all three compressors kicked on at the same time..it could be a fire hazard.

Yes, an extension cord can drop the available power to a unit, especially when the unit's compressor is active. Also note: These units work best when the air around them is cold. They transfer heat from inside to outside. The effeciency goes up as the ambient air temperature goes down. Or in other words.. The hotter the air around them becomes, the more crappy they work.

Watch for heat on your extension cord! Change to a higher power cord if you can. Shorter is good too. Adjust temperature for minimum smoke. (that's an insider joke)

So.. yes.. a Long underated cord can limit power to your units and pose a fire hazard. Add up all the MAX amps all three units could draw, in worse case, and confirm the amps rating on the cord and wall socket are enough to cover the maximum possible load.

Also, There are two coils to a unit. One inside (cold) and one outside (hot), usually on the back or bottom. Make sure there is good air flow around the exposed (hot) coils to improve effeciency.

Final note: The worse thing you can do (without knowing the harm), is tip a unit up-side-down.. or even tip it like.. say.. 90". The compressors have oil in them.. if that oil gets into the coils, it can clog them and ruin the effectivness of the unit.

Best of luck,
Dave :^)
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Re: Refrigerator Not Cooling ....

Postby CanadysPeak on July 9th, 2013, 6:21 pm 

Running a fridge on an extension cord is a violation of code everywhere in the US. That's not what's wrong with your fridge, but it could well burn down your house; if it does, the homeowner's insurance company may refuse to pay.
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Re: Refrigerator Not Cooling ....

Postby Watson on July 9th, 2013, 7:14 pm 

Hi Dave,
My life lesson taught that if you tip a fridge on its side for transport the compressor oil will drain out from the compressor but drain back once it is put upright. So leave it upright for an hour or so, before plugging it in. Is this about right?

Also, I get points for gauge and length.
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Re: Refrigerator Not Cooling ....

Postby Dave_Oblad on July 9th, 2013, 8:18 pm 

Hi Watson,

Points granted..lol.
Unfortunately, once oil gets into the coils, the oil may not be able to get back into the compressor (trapped).

Refrigeration is really simple. You have a compressor, one inlet and one outlet, with one coil/tube connecting the inlet and outlet. At midway along the single coil/tube the coil/tube is pinched. Thus many call it two coils or tubes, but actually it is just one coil/tube.

The compressor (push side) builds up pressure on one side smushing the gas into a condensed state.. this makes the gas hot. Air is blown across this hot part of the coil to cool it down and take away the heat. The other side of the compressor is sucking of course, which stretches tha gas (constricted by that pinch), making it cold. Air blown across this cold side cools off and it (tube) absorbs heat. So we get a hot side and a cold side with a pinch separating the two.

If the oil gets into the pinch (tiny pin-hole) then it can clog and mess up the whole effect. The whole thing merely transfers heat due to the compression and expansion of the gas in the tube. Temperature is regulated by how often the compressor is engaged. If you kick off the unit during compression, it may not be able to start up again, against the pressure, until said pressure bleeds back off.

Bit of knowledge can't hurt..lol.

Best wishes,
Dave :^)
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Re: Refrigerator Not Cooling ....

Postby vja4Him on July 9th, 2013, 11:01 pm 

Wow .... That's a lot of information! Thanks everyone! I will rearrange everything on the patio, and get the two refrigerators as close to the outside outlet as possible. I'm sure the extension cords are heavy enough, but they are long.

I will also buy two shorter heavy-duty extension cords, one for each fridge, just to be safe. Unfortunately, we don't have any outlets at the patio, only on the outside of the back door. I do have the best power strips, one for each fridge. Would the power strips help with any possible fire hazard?
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Re: Refrigerator Not Cooling ....

Postby vja4Him on July 10th, 2013, 12:31 am 

We measured the Voltage for both Refrigerators, and it was 120 Volts for both. When I turned on a lamp, the Voltage did not decrease.

Turned on the portable air cooler, which dropped the voltage to 117 volts, which went back to 120 when we turned the air cooler off.
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Re: Refrigerator Not Cooling ....

Postby Watson on July 10th, 2013, 12:35 am 

I suggest filling the largest fridge with beer, as a sample and monitor the temperature. Dave and I can come over and judge if the beer is satisfactorily cold enough. Dave can inspect the equipment and power supply, at no charge. Where do you live.
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Re: Refrigerator Not Cooling ....

Postby CanadysPeak on July 10th, 2013, 9:22 am 

vja4Him wrote:We measured the Voltage for both Refrigerators, and it was 120 Volts for both. When I turned on a lamp, the Voltage did not decrease.

Turned on the portable air cooler, which dropped the voltage to 117 volts, which went back to 120 when we turned the air cooler off.


Oy vey! Power strips, eh. Are these the type of power strips that have surge protection built in? If so, these may well be the problem, and you can't measure it with an ordinary voltmeter. Here's what may be happening:

The surge protection limits current. A fridge compressor has a very high inrush current when it starts. If you limit that, the compressor will often trip whatever type of protective device it has (maybe high pressure cutout). Thus, you will have a fridge that seems to work (the light comes on, the fan may blow) but in which the compressor never runs or doesn't run for long. When you measure it, a digital multimeter won't be fast enough to show any change. An analog meter might, but it'll just be a quick dip. You would have to look at this with a peak voltmeter or a scope.

I still recommend to never, ever use an extension cord for anything except a portable appliance (power drill, etc), but I say that power strips should absolutely never be used for anything except devices that can stand to be floated off ground and can withstand low voltage - a computer, a desk lamp, a clock for example. Go get a real extension cord, no more than 15 feet long, 3 wire, and 14 AWG. If it's still running hot, you gotta put a wattmeter on it or just call the service guy.

Another possible culprit is the temperature sensor. Sometimes you can get to those, test them, and replace them. Sometimes you have to pretty much disassemble the whole fridge to get to the sensor, in which case you might remember that you can get pretty good used fridges for less than $200.
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Re: Refrigerator Not Cooling ....

Postby tirealert on July 13th, 2013, 12:23 am 

In the frig there is a defrost cycle, if this is not working (usually the temp sensor) and it never goes into the defrost cycle the evaporator coils frost up and not let air pass, hence no cooling.
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Re: Refrigerator Not Cooling ....

Postby dady551 on August 29th, 2013, 2:40 pm 

there may be an easier solution to your problem although i doubt its the right one . you mentioned that refrigerator is covered on all 4 sides plus you also have 2 other refrigerators working alongside . a refrigerator needs proper ventilation to blow hot air out. if it is not getting ventilated well enough well then there is your problem . an easy test :
put a pedestal fan near the back side (ventilation area) of the refrigerator and run it for a day . see if it works :P
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Re: Refrigerator Not Cooling ....

Postby mamaDhea on August 26th, 2014, 8:47 am 

The air ducts between the freezer and the fridge might be blocked by ice. Try emptying the fridge and freezer and unplug it for several hours. Leave both doors open. Wipe out any water and try again...
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Re: Refrigerator Not Cooling ....

Postby Calokonik on November 21st, 2018, 8:04 am 

I know it's an old thread, but maybe it will be a timely resurrection for someone
I agree with mamaDhea, we had the same problem and when we defrosted our refrigerator it's helped(but only first time).
Next time we called master and he sad that now refrigerators are being made for 5-7 years, and then throw it away. Of course, it was possible to fix the refrigerator, but no one gave 100% guarantee that it would work as long. We decided to buy a new refrigerator, of course it was very difficult to choose, since there are 1000 of them now.
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Re: Refrigerator Not Cooling ....

Postby TheVat on November 21st, 2018, 10:28 am 

"master" ??
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