- Thermostat or temperature sensor in the freezer compartment (in double-compressor refrigerators)
The thermostat (in electromechanical refrigerator models) regulates the temperature in the chamber. In most cases, when it fails, the cooling does not turn on and the compartment does not freeze. The cause of the thermostat failure, more often than not, is due to a depressurized bellows or a damaged contact group.
- Freon leakage in the freezer compartment refrigerant circuit (in the dual-compressor models)
Freon is a refrigerant that circulates through the closed loop system of the freezer compartment refrigeration circuit. Because of the pressure drop after passing through the narrow capillary tube in the “wide” evaporator, freon boils and takes heat from the chamber. But if the circuit loses its tightness and a leak occurs, the cold-productivity of the compartment decreases. In the beginning, it does not freeze enough, and after the freon evaporates completely, the freezer stops cooling at all.
In the freezer, the leak points are usually in the steel perimeter heating circuit of the freezer, in the evaporator, or in the piping connections.
- Refrigerant leakage in single-compressor refrigerators with “drip” defrost or No Frost
Freon, circulating through a sealed cooling circuit, draws heat from the chambers of the refrigerator. In this way, cooling takes place. If the tightness of the circuit is broken, a leak occurs. Initially, there is enough refrigerant to cool the cooling compartment when the refrigerant motor is constantly running, but the freezer already does not freeze well. Then, when there is no freon left in the circuit, the compressor shuts down and the refrigerator stops freezing.
In “drip” models, leaks can occur in the refrigerator compartment evaporator, the freezer perimeter heating circuit, or tube connections.
In the No Frost refrigerators, micro holes can form in the No Frost evaporator, steel perimeter heating circuit of the freezer compartment, and tube connections.
The main causes of leakage are corrosion.
- Freezer compartment capillary tube clogging (in twin-compressor models)
The capillary tube is the thinnest part of the piping. It is necessary to create a pressure difference in the system and the boiling of freon in the evaporator. Because of the small cross-section, it is in it that clogging occurs. Paraffins, which are formed in the system as a result of the chemical reaction of freon and machine oil, clog the pipe, and refrigerant circulation is broken. As a result, the freezer does not cool.
Partial capillary tube clogging in single-compressor refrigerators with “drip” defrost or No Frost system
The capillary tube is an important assembly in the refrigerator. It is selected with the cross-section and length in such a way so as to create a pressure differential at which freon boils in the evaporator and takes heat from the refrigerator. Together with freon, machine oil from the compressor circulates through the cooling circuit. As a result of the interaction of oil and refrigerant, kinds of paraffin are formed, which clog the capillary tube.
With partial clogging, less freon enters the evaporator per unit time. In addition, due to the reduced cross-section of the capillary tube, the pressure drop before and after the capillary tube increases. As a result, the refrigerant quickly boils off at the beginning of the evaporator. This amount of cold is enough to cool the refrigerator compartment, but there is not enough cold for the freezer compartment. Therefore, the freezing compartment does not freeze, while the refrigerating compartment works properly.
- Crack of the compressor of the freezing compartment or breakage of its valves (in the dual-compressor models)
The compressor is the heart of the refrigerator. It is the one that drives the refrigerant that circulates through the system and cools the refrigerator chambers. Over time, the compressor internals wear out and mechanical failures occur:
“wedging” of the compressor – mechanical blockage of components inside it due to wear or changes in their geometry;
Damage or deformation of motor inlet or outlet valve.
In both cases, the refrigerator freezer motor seems to work, but does not create pressure to cool the freezer, so it does not freeze.
If your freezer has stopped freezing and you don’t know what to do. The best solution is to contact a professional. The technicians at Chula Vista Appliance Repair Company have repaired over 20,000 freezers, and they can definitely help you. We are open 24/7, if you need to respond to a call right away, our handymen will be there in as little as 15 minutes.