The "moisture in the system" defect physically represents the presence of a certain amount of water in any of the states of aggregation (liquid, vapor, crystals) in the cavity of the refrigeration unit.

Removing moisture when it enters the household refrigerator system is a difficult, time consuming and costly problem. This problem can also reappear months and years after the elimination of its external signs. A small amount of water is enough to seriously impair the functioning of the refrigeration unit.

If a pressure gauge is connected to the filling pipe of the refrigerator, and the motor-compressor is turned on through devices that control current or power consumption, then the external manifestation of the presence of water in the system will be as follows: suddenly, during the refueling process, the suction pressure begins to noticeably drop, the power or current consumed decreases to the operating values on a vacuum. The noise of a running motor-compressor is also typical, as for working in a vacuum. The noise of movement and refrigerant boiling stops, despite the operation of the motor-compressor. A “smooth” or “sharp” increase in the manifestation of a defect depends only on the amount of moisture in the system, and the more moisture there is, the earlier and more pronounced the manifestations. If the unit is stopped at this time, pressure equalization does not take place. That is, initially, the signs correspond to the “blockage in the capillary tube” defect (hereinafter referred to as CT). The way it is. But unlike the blockage caused by contamination of the system with various mechanical inclusions, which practically cannot be eliminated by itself, the defect we are considering is reversible. The fact is that when moving along the CT, the droplet moisture at the entrance to the evaporator, where the refrigerant begins to be throttled and there is the lowest temperature in the unit, crystallizes, turns into ice and freezes to the cooled walls inside the CT. If there is a lot of it, when it freezes, it blocks the passage with a kind of plug and completely disrupts the circulation of the refrigerant. But as soon as the temperature of the CT walls becomes positive, the ice plug melts and the refrigerant pressure in the condenser (condenser) is able to “spit out” this plug into the evaporator cavity. Therefore, it is easy to distinguish moisture from mechanical blockage - it is enough to warm up the CT inlet to the evaporator in any suitable way (for example, using a lighter, burner or hair dryer), and after a short time you can hear a sharp characteristic sound of gas breakthrough from the condenser. After that, the movement of the refrigerant begins with a decrease in temperature and a rise in pressure in the suction line. Often, in the presence of abundant moisture, “sticking” (ie, freezing of moisture) is repeated again and again, at short intervals.