Freezer in a cold garage

Discussion in 'Highly Technical' started by Markbnj, Dec 18, 2009.

  1. Markbnj

    Markbnj Elite Member <br>Moderator Emeritus
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    Ok, maybe not highly technical, but I couldn't figure out where else to put it. And in my case the refrigeration cycle has always been mystifying enough to qualify as highly technical.

    So, we have two freezers in our garage: the top section of a normal over/under reefer, and another horizontal unit my Dad gave us. On certain days during the winter the garage temperature will fall below 25-30 degrees or so, and the food in the freezers will actually soften.

    I'm not sure what's going on. Any thoughts?
     
  2. Gibsons

    Gibsons Lifer

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    Do you have a thermometer in the freezers so you can see what their internal temp really is?


    wild guess, probably wrong: the cold temps in the garage cause the gasket seals around the door to harden a bit and get leaky.
     
  3. Jeff7

    Jeff7 Lifer

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    Maybe some of the coolant in the lines gets cold enough to freeze, impeding its normal flow?
     
  4. Modelworks

    Modelworks Lifer

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    That is normal.
    The way frost free freezers become frost free is they have a timer. The timer turns on for 20 minutes every 24 hours. There are heating coils inside the walls of a chest freezer and behind the back panel where the fan is in a refrigerator. Those coils run for a few minutes till their thermostat attached to them clicks off. That removes the ice build up that normally happens without them. So on a cold day the heater could be running longer than normal because of a door seal or leak, it runs longer because the cold air from the outside is getting inside , sort of like running your homes heat with a window cracked.
     
  5. Rubycon

    Rubycon Madame President

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    I don't think a garage in Casey, Antarctica could get cold enough to freeze R12. ;)

    Low ambients could be affecting the defrost cycle. If it gets cold enough open the door and unplug it. ;)
     
  6. dkozloski

    dkozloski Diamond Member

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    Freezers and refrigerators in a cold garage can have the lubrication oil in the compressor get so stiff that the compressor won't start and will trip out the auto reset breaker. In an extreme case the compressor motor can burn out because it doesn't turn. In either case the freezer temp goes to ambient. Freezers in the garage are problematic.
     
  7. Rubycon

    Rubycon Madame President

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    Installing a band crankcase heater will prevent that. ;)
     
  8. MagnusTheBrewer

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    Or, the OP could just leave the wrapped food on the floor of the garage. :)
     
  9. BrownTown

    BrownTown Diamond Member

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    Kind of remoinds me of another thing which I learned recently when it was 20 degrees out. While you normally think of a coke machine as cooling a drink on a hot summers day they actually have heating coils so they cokes wont freeze and burst when it gets really cold outside. Maybe a freezer does the same thing and starts heating if it is really cold outside?
     
  10. Rubycon

    Rubycon Madame President

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    Hot gas bypass.
     
  11. dullard

    dullard Elite Member

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    The answer is different for your two freezers.

    For the refrigerator/freezer, unless you spent a very large amount of money on that unit, you almost certainly have a very simple temperature control loop. Almost all consumer units operate about the same: they have one temperature sensor in the refrigerator to control the temperature of BOTH the refrigerator and the freezer. Meaning that it cannot control both temperatures. Instead it makes some assumptions (such as assuming the doors are shut most but not all of the time and that the unit is at room temperature) and hopes for the best. Putting the unit in the garage violates the units assumptions and the result is the freezer doesn't freeze.

    Basically, the unit produces only one source of cold air (below freezing) and diverts that cold air as needed. The unit will use more and more cold air until the refrigerator is at the set temperature (one of your dials). You probably have a second dial for the freezer temperature. What actually happens is that dial adjusts the percent of cold air going to the freezer vs the refrigerator. So, in the proper environment, you put more cold air in the freezer than the refrigerator. Thus, when the refrigerator is a bit above freezing temperature, the freezer will be a bit below freezing temperature. By adjusting the dial, you can give more cold air to the freezer and less to the refrigerator. Thus when the refrigerator is kept at a constant temp, the freezer will get colder and colder as you divert more and more cold air to the freezer section.

    But, the problem is when you put the unit in a cold garage. The refrigerator is cold without the need for any cold air. The entire compressor unit shuts off since the one and only temperature sensor says the refrigerator is cold enough. No cold air is blown into the refrigerator OR the freezer. The units only temperature sensor and doesn't know the freezer is too hot. Both units become the same temperature and your food thaws.

    This is why you should NEVER put dual refrigerator/freezer units in the garage if the garage can approach freezing temperatures. First, you'll thaw your freezer and spoil that food. Second, you'll cut your unit's lifespan from maybe 30 years to maybe 5 years. Dkozloski described why you'll destroy its lifespan. Get that out of your garage ASAP.



    The single unit is fairly easy to explain. Since the garage is right near freezing, the unit doesn't need to run its compressor to cool things down. But, the anti-frost components still run. You essentially have a freezer where you are using only the heating element. Of course some food near the walls will thaw. The solution is to simply turn down the temperature of the freezer to make certain that the compressor kicks in. Of course, you still may be shortening its lifespan by having it in the garage.
     
    #11 dullard, Dec 21, 2009
    Last edited: Dec 21, 2009
  12. DominionSeraph

    DominionSeraph Diamond Member

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    Other way. Refrigerator switch controls the vent from the freezer, freezer switch goes off temps.
     
  13. kalrith

    kalrith Diamond Member

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    Some refrigerators and freezers (example) are made to go in the garage and have a built-in heater to keep items in the refrigerator from freezing in the cold temperatures. I would assume that they would combat your problems as well, but it would be a good idea to read reviews to confirm that.
     
  14. Markbnj

    Markbnj Elite Member <br>Moderator Emeritus
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    Thanks to everyone for the responses on this thread. I posted it, and then some crisis or other at work came up and drove it out of my head. Next thing you know Christmas is in the rearview mirror.

    Anyway, it sounds to me like dullard gave the most comprehensive explanation, and now that I understand that the unit is ducting air between the freezer and refrigerator to maintain temperature it all makes perfect sense. By the way, this is a rather cheap over-and-under model, so it certainly doesn't have anything more sophisticated than the simple mechanism you described.

    According to my wife the horizontal freezer doesn't suffer from the same problem, so my question is: what if we turn the temp on the combo's freezer up to its highest setting and empty its contents into the horizontal? Would it then be safe to keep operating the refrigerator portion of the combo?

    Thanks again for all your insights, and Happy New Year to you all.