Refrigerator repair tips
A refrigerator is an apparatus designed for short-term preservation of food products at home by means of artificial cooling.
Types of Refrigerators
Refrigerators, depending on the type of refrigeration machine, are divided into compression, absorption and thermoelectric.
The first refrigerators with artificial cooling (compression) appeared in 1910 in the United States.
The refrigerator is a metal cabinet with a sealed refrigeration unit built into it. Inside there is a refrigerator with shelves for placing products. Between its walls and the outer casing is placed thermal insulation. Air is cooled by heat exchange between it and the cold surface of the evaporator. The necessary temperature regime in the refrigerator is ensured through short-term periodic (cyclic) operation of the refrigeration unit, the inclusion of which is carried out using a temperature switch.
According to their purpose, refrigerators are divided into 4 categories: for storing unfrozen products (there is no low-temperature compartment), short-term storage (for several days), medium-term storage (up to 2 weeks) and long-term storage (up to 3 months) of frozen products. The belonging of a refrigerator to one or another category is determined by the presence of a low-temperature compartment and the air temperature in it.
For consumer information, old domestic refrigerators designed for short-term storage were marked with one asterisk (temperature in the low-temperature compartment -6 С), medium-term - two (-12 С), long-term storage - three (not higher than -18 С). All such refrigerators are two-temperature. Refrigerators service should be made by professional team.
According to the design, the models are single, double and multi-chamber.
In two-chamber refrigerators there is a reinforced heat-insulating partition between the chambers (low-temperature and with a positive temperature), and each of them is equipped with a separate door. Multi-chamber refrigerators are equipped with several, at least three, chambers with separate doors for storing various products.
Features of refrigerators
The degree of automation of service distinguishes refrigerators with manual, semi-automatic and automatic removal of snow from the evaporator.
Depending on the method of air circulation in the refrigerator, refrigerators with natural circulation and with forced circulation created by the fan are distinguished. In a refrigerator with natural convection of air, each chamber, as a rule, is cooled by a separate evaporator. In refrigerators with forced air circulation, the fan draws air through the evaporator, made in the form of a tubular coil with plate fins. The evaporator and fan are usually mounted on the rear wall of the low-temperature compartment. Most of the cold air (75-85%) is supplied to the low-temperature compartment, and the rest to a chamber with a positive temperature. In these refrigerators, frost deposits on products and walls are completely eliminated. The moisture contained in the air settles on a finned tube evaporator located behind the chamber wall, and therefore only dry air enters it. Since the evaporator does not come into contact with food, heating it during thawing does not affect the temperature of the frozen food. Therefore, it is possible to defrost automatically several times a day.
By design, refrigerators are stationary, divided into floor, wall, built-in (in the kitchen or living room furniture unit) and portable (mainly absorption and thermoelectric).