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.
Minimum temperature
The lowest temperature that the freezer can maintain in normal operation. First of all, the duration of food storage in the freezer depends on this parameter: it is believed that a temperature of -12 ° C is enough to preserve food for a month, -18 ° C – 3 months, -24 ° C – up to a year. At the same time, it must be taken into account that not only temperature affects the shelf life but also the type of product and its quality before freezing.
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.
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.