How do refrigerators and freezers generate cold

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«Can I set up my fridge or freezer in an unheated room (basement or garage) or even on the balcony in winter? That would help to save electricity, wouldn't it? "

- At first glance, this seems like a good idea, because one concludes from the finding that the colder it is, the less electricity the device would need to use to operate. Basically, it seems to be absurd to use electricity to generate coolness inside the device when it is winterly cold outside!

In practice, manufacturers strongly advise against keeping a refrigerator or freezer out of its range Climate class (see below), i.e. not below 10 ° C for most devices sold in Switzerland. However, there are some models that can be operated in colder temperature ranges. This includes freezers that can withstand a temperature of 5 ° C (brand Liebherr) and even remain functional down to -15 ° C (brand Beko, Freezer Guard model).

Old models can withstand the cold better

Some older fridges and freezers can work in the 3-4 ° C range without major problems, even if the manufacturers advise against it. Modern devices, on the other hand, which have been optimized to achieve particularly high energy efficiency, in most cases require that their climate class be taken into account, otherwise there is a risk that the compressor will become stuck or that the compressor will age prematurely. If it is placed in the cold, the device could break down, which would not be too bad for food in a refrigerator, as it is stored between 2 and 8 ° C. For deep-frozen foods, however, this would be a lot more problematic, as they have to be stored at minus 18 ° C.

The climate classes of refrigerators and freezers

Every refrigerator or freezer usually has a device nameplate (often attached to the back of the device), on which not only its electrical data are noted, but also those of its own Climate class - Or in other words: the minimum and maximum ambient temperatures in which the device is to be operated. Because a refrigerator that runs in the tropics does not contain the same gas mixture as a device that is intended for moderate climates. Always check this information when buying a refrigerator or freezer. And not just the minimum temperature, because in the course of climate change, refrigerators and freezers also have to withstand warmer temperatures.

A thermometer with a memory function

If you choose to own your fridge or his Fridge-freezer combination If you place it in an unheated place in winter, you should be aware that the temperature can drop below the recommended ambient temperature and that the food stored in the refrigerator can freeze.

In order to determine whether the chilled or frozen food has been exposed to too low or too high temperatures for a long time, you can place a digital thermometer with memory function (cost between CHF 10 and 25) between the food, which not only shows the minimum and maximum temperature, but also the duration of these upper and lower ranges. There are also thermometers with a probe that send an alarm signal to a receiver base in the event of undesirable temperatures. So you can stay in your kitchen and still be warned quickly if the freezer in the garage has a problem ...

Do not buy a refrigerator or freezer that is too large

If you intend to buy a new device, it is important to consider not only the size, but also the energy consumption. On the energy label (compulsory for new devices) you shouldn't just let yourself be misled by the A ++ and A +++: Take into account the annual consumption in kWh. Also keep in mind that the bigger a freezer, the more likely you are to store food in it that you will eventually forget for years. But frozen foods also have a best-before date. Homemade dishes, for example, should be consumed within a few months.

Small notes on cold and warm

  • A refrigerator (or freezer) can be left OFF in the cold. Before the devices come into the shops, they are often easily exposed to the cold during transport or storage.
  • If a refrigerator or freezer is placed on the balcony or in the garage where the device is exposed to the summer sun, it must run at full speed to maintain the temperature. The electricity costs can therefore be very high.
  • Fridges and freezers give off more heat than they produce cold. Think of it as a small radiator that turns on sporadically. These devices tend to warm up the rooms in which they are placed.
  • Regardless of whether a refrigerator is packed full of food or almost empty: it will always need roughly the same amount of power for cooling (if its operating mode is controlled by an internal thermostat, as is usually the case).
  • Fridges and freezers have one on the back radiator (sometimes hidden behind a cover). This radiator is there to dissipate the heat from the gas mixture compressed by the compressor. It can get very hot. In order for the cooling device to work properly, it is very important that (if possible fresh) air can circulate around the radiator.

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