Comparison Liebherr CU 3515 white vs Liebherr CNef 3515 silver

The total capacity of the refrigerator is the total capacity of all the main working chambers: refrigerating, freezing, zero, and wine chambers. The set of these chambers, of course, will be different in different models (see more about them above). Here we note that large volumes, on the one hand, simplify the storage of numerous products and, on the other hand, affect the dimensions and price of the unit. It is also worth considering that refrigerators of the same total capacity may differ in the capacity of individual chambers.

Inverter compressors are called compressors that can smoothly change the power of work.

The compressor is a pump that pumps freon through the cooling circuits of the refrigerator. A conventional (non-inverter) compressor has only one power level, and the cooling intensity changes due to periodic switching on and off: the longer the time of continuous operation and the fewer interruptions in operation, the stronger the cooling, and vice versa. Such a design is inexpensive, but it has several disadvantages — in particular, uneven cooling, relatively low temperature control accuracy, and a tendency to create power surges in the network where the refrigerator is connected. Inverter compressors run continuously, while the pump power varies depending on current needs. Thanks to this, refrigerators with compressors of this type are free from the described disadvantages and have some other advantages, such as low noise level and energy efficiency. On the other hand, such units are quite expensive.

The No Frost function prevents the formation of frost inside the refrigerator. The general principle of its operation is that excess moisture is blown out of the working chamber by a special fan, not having time to settle on the walls and form frost.

This function is most relevant for the freezer, although it is technically easy to provide in the refrigerator. Therefore, refrigerators with No Frost in all compartments are the most popular nowadays, much less often this system is installed only in the freezer, and extremely rarely — only in the refrigerator (usually in such models there is no freezer at all).

The No Frost function significantly simplifies the user's life. It eliminates the need to manually defrost the refrigerator and even eliminates the need for automatic defrosting systems (see "Features"). The reverse side of this convenience is that such systems absorb moisture not only from the air but from the food inside too. So for long-term storage, the contents must be tightly packed — otherwise, it dries quickly. In addition, the presence of No Frost inevitably increases the overall cost of the fridge. So if these moments are critical for you, the fridges without No Frost may well be the best choice.

The total capacity of the main working chamber of the refrigerator. If there are separate zero chambers, compartments for wine and other additional functions, this paragraph takes into account only the volume of the refrigerating chamber itself, without additional equipment. In the smallest modern units, this figure does not even reach 100 liters, in the largest it can exceed 400 liters.

The choice of capacity depends on the actual storage needs of the products. At the same time, both the volume of stocks and the frequency of their replenishment (every day, once a week, etc.) matter. The chamber should not be stocked completely; this adversely affects the quality of the refrigerator. On the other hand, it is worth remembering that large volumes accordingly affect the dimensions and price of the unit.

In general, for one or two people, a capacity of 200 – 250 liters, or even less, is considered quite sufficient. The optimal capacity for a family of three is about 250 – 300 liters, for four to five people — 300 – 350 liters, and larger volumes are really needed mainly for specific situations when food has to be stored in large quantities and for a long time.

Forced cooling mode, in which the intensity of cooling the refrigeration compartment is significantly increased. It is an analogue of the fast freeze described above, used in the refrigerator compartment. Fast cool is also intended mainly for situations where a lot of foodstuff must be loaded inside at a time — it avoids a critical increase in temperature inside the refrigerator. This mode also needs to be turned on in advance and turned off after a certain time. In some models, the shutdown occurs automatically, but the presence of this feature needs to be specified separately.

This function means that there is a built-in fan that circulates air around the refrigerator compartment. It contributes to the evenest distribution of cold and more efficient cooling than in units without a fan, where the air moves only due to natural convection. The main disadvantages of dynamic air cooling are the increase in noise level, energy consumption and the cost of the refrigerator.

The capacity of the freezer installed in the refrigerator. Such a chamber is designed to store products at temperatures well below zero (on average -18 °C). Its capacity is related to the total capacity of the refrigerator (and the capacity of the main, refrigerating chamber). However, there is no strict dependence here — models with a similar volume of the refrigerating chamber can be equipped with freezers of different sizes.

When choosing by capacity, it is worth considering how much frozen food you plan to store at a time. Note that it is undesirable to fill the freezer completely — this negatively affects the efficiency of work. However, if this chamber is planned to be used only occasionally, and you do not plan to keep numerous products in it, you can not chase after the capacity: for such cases, 25 – 50 liters, or even smaller capacities, are enough. In the smallest modern refrigerators, the freezer capacity does not exceed 10 liters. And vice versa, very roomy freezers come across — for 176 – 200 liters and even more. Such volumes are typical mainly for side-by-side and French door units (see "Product type"). However, they are also found in models of the classic two-chamber layout.

The autonomy time provided by the refrigerator when the power is turned off.

Often, this parameter describes the capabilities of the freezer. In such cases, the autonomy time is indicated as the time during which, at an outside temperature of +25 °C, the temperature in the filled freezer does not rise above -9 °C (this level is considered critical for the storage of frozen foods). Accordingly, the actual autonomy time may differ from the claimed one — depending on the ambient temperature, the frequency of opening the refrigerator, etc. However, this parameter describes the quality of thermal insulation quite accurately, and it is possible to evaluate different models and compare them with each other.

Also, autonomy time can be given for models without freezers: in such cases, we are talking about the time during which the temperature in the refrigerator compartment remains at an acceptable level under approximately the same conditions.

Approximate amount of fresh food that a refrigerator can completely freeze from room temperature to freezer operating temperature in 24 hours. Power up to 10 – 15 kg/day will be quite enough for everyday use, but if you plan to freeze food in large volumes and often — you should pay attention to more performant freezers.