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How cold freezer or freezer should be? Instructions to Freezer Temperature Adjustment.

According to the Finnish food bureau, temperature in a freezer or fridge-freezer should be -18 °C. -18 °C is the optimal temperature for the freezer in terms of energy efficiency and food preservation. However, if you freeze fresh food in large quantities at once, then the freezer should be even colder. To ensure fast freezing and better preservation, the temperature should be around -22 °C.

Freezer is too warm

According to FDA, too warm freezer predisposes food to harmful growth of microbes and shortens the lifespan of food products. Too warm fridge also cools down food too slowly and freezing doesn’t happen fast enough.

Freezer is too cold

A too cold freezer can impose problems. Cooling takes a lot of energy, but freezing temperatures can also change the taste and texture of food. This does not make it inedible or dangerous, but it’s a good idea to take this into account, especially when freezing meals – choose airtight containers for this purpose. On the other hand, a freezer that is too warm exposes food to growth of harmful microbes.

Proper temperature in a chest freezer

Temperature in a chest freezer should be the same as in a regular freezer, at -18 °C. Often, a chest freezer could be used to freeze larger quantities of food. If you know that you will fill up to freezer with more food, you should set temperature to below -20 °C.

If you have a chest freezer, place one Ruuvi sensor at the top of the freezer and the other at the bottom of the freezer. Sometimes the built up frost in the freezer can cause the cover seal to leak. In this case, we suggest placing the Ruuvi’s measuring device at the top of the freezer to detect undesirable changes in temperature.

Energy efficiency of a freezer

Monitoring the temperature in a freezer is beneficial as you can increase the energy efficiency of this home appliance. Refrigeration appliances consume a lot of energy, especially if they cool a space unnecessarily. In addition, the frost building up to the walls of a freezer decreases the energy efficiency of the machine significantly. The temperatures mentioned in this article are sufficient for food safety. If your freezer is colder than the temperatures mentioned in this article, you can warm up your freezer a bit and hence decrease your energy consumption.

A large amount of ice accumulated in the freezer increases energy consumption and weakens the operation of the freezer. The picture below shows how the temperature before defrosting varies by about 4 degrees and only one degree after defrosting.

Temperature variation before and after defrosting.

With Ruuvi’s sensors, you’ll know exactly what temperatures your refrigerators are running at. The graph feature in the Ruuvi app is perfect for monitoring the temperature of your fridge or freezer. You can clearly see at which temperatures your refrigerator is at its coldest or warmest. This allows you to conveniently adjust the appliance’s thermostat to match actual temperatures.

Monitor the temperature in your freezer!
With RuuviTag, you can always know accurately the temperature in your freezer.

Monitor the temperature in your freezer!

With RuuviTag, you can always know accurately the temperature in your freezer.


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