Capacity
It is the total working capacity of the freezer. A larger capacity allows you to accommodate more products but affects the dimensions and cost of the unit. Therefore, when choosing according to this parameter, you should not chase after the maximum capacity but the capacity you really need. For example, the average required capacity is 50 litres per person. And when choosing a display chest freezer (see "Product type"), you need to take into account the number of products offered for sale.
It is also worth considering that the freezer is often divided into several compartments (see below) - which means that a large capacity does not guarantee that large pieces of food can fit in the device.
Power failure autonomy
The amount of time the freezer keeps food cold enough when the refrigeration system is turned off, for example, due to a breakdown or power outage. Technically, the power failure autonomy for each model is calculated differently; For example, for a freezer with an operating temperature of -18 ° C, this is the period during which the products in the chamber heat up from -18 ° C to -9 ° C. To sum up, the time is indicated during which the frozen products are guaranteed not to heat up to a temperature at which they could lose their properties.
Freeze capacity
One of the main indicators of freezer performance is the approximate amount of fresh food that the freezer can completely freeze from room temperature to the minimum operating temperature in 24 hours. For domestic use, a power of 10-15 kg/day is considered quite sufficient. More performant models may be required if you have to freeze a lot of food at a time or for industrial purposes.
Door alarm
It is a system that monitors the closing of the freezer door. If the door is not closed for a long time or is not closed tightly enough, an audible or light (depending on the model) signal is given. It helps to avoid a critical increase in temperature in the working chamber and preserves the quality of the products.
Energy class
The energy class shows how economical the freezer is in terms of electricity consumption. Initially, the classes were designated in Latin letters from A (most economical) to G (high power consumption). Recently, improved classes A+, A++ and A+++ appeared (the more pluses - the more economical the device).
It should be borne in mind that this indicator represents not the actual energy consumption but the efficiency of the unit compared to similar models. Therefore, a small class A freezer may have a lower power consumption than a large class A++ model. And other things being equal, a more economical device, as a rule, costs more, but this difference can quickly pay off during the operation.
Energy class (new)
This parameter shows the efficiency of electricity consumption by the freezer. Classes are designated in Latin letters from A to G, in ascending order of energy consumption. It was originally conceived until more energy-efficient models pulled up to class A, which eventually received the marking A+, A++, and A+++. Further development of technology has made it possible to go even further and, in order not to produce pluses in energy efficiency labelling, in March 2021, manufacturers returned to the previous indices from G to A, where A is the most energy-efficient freezer. Accordingly, the 2021 models will have modern markings, while older models will be marked the old way.
Energy consumption per year
It is the average amount of energy consumed by the freezer in a year of operation. Of course, these figures are not absolutely accurate. The actual power consumption may vary depending on the specific operating conditions. However, this parameter makes it possible to evaluate the consumption of the device and compare different models with each other. At the same time, it often turns out to be more convenient and visual than the energy consumption class (see above) because, in this paragraph, we are talking about a specific figure (from which you can also calculate the cost of electricity consumed).
Climate class
The climate class to which the freezer corresponds.
As the name implies, this parameter describes the environmental conditions for which the unit is designed. The warmer it is around, the more powerful the freezer should be and the better thermal insulation it should have. Specific classes are indicated by letters. Here are the most popular options:
— SN (subnormal). Models for a cool temperate climate have an operating range from +10 °C to + 32 °C. Such a unit can be useful in a poorly heated room where the temperature can drop below +16 °C — for example, on the veranda of a private house, in a garage, etc.
— N (normal). Freezer for a temperate climate, with an operating temperature range of +16...+32 °C. Such a unit is suitable for most residential apartments and houses in mid-latitudes.
— ST (subtropical). Models for subtropical and humid tropical climates. Normally they work at the range of external temperatures +18...+38 °C.
— T (tropical). Refrigerators for dry tropical climates. Designed for temperature range +18 °C to +43 °C.
Also, note that there are many models on the market with an extended temperature range covering several classes. For example, a unit labelled N-ST will have a temperature range of +16...+38 °C. These freezers are indispensable in climates, conditions which are not covered by one standard class — for example, in cold winters and hot summers.
Noise class
This parameter allows one to decipher the noise level in decibels. It is marked, like other classes, in Latin letters, where A is the quietest class of wine cabinets.