Why does a refrigerator need a compressor? The compressor ensures the pumping of the refrigerant through the heat exchange system, i.e. it is responsible for the quality of the cooling. Toronto appliance repair experts offer to take a closer look at compressor types existing today and their features.
The design features of the compressors make it possible to divide them into three categories:
- Piston
- Rotary
- Linear
Piston (reciprocating) compressors
This type of device is in many ways similar to the one-cylinder internal combustion engine. An identical crankshaft driven by an electric motor is inside it. Compressors of this type can be produced in various versions:
- Hermetic. In this option, the electric motor and compressor are housed in one sealed housing. They are mainly installed in low/medium capacity refrigeration units. Their rated power ranges from 1.5 to 30 kilowatts.
- Semi-hermetic. There the electric drive and the compressor are directly connected and are located in one collapsible housing, making fridge repair work possible. They are used in refrigeration units with a capacity above average. Their rated power ranges from 30 to 300 kilowatts.
- Open. These devices have the engine located outside. They are mounted in refrigeration units of various capacities.
Pros:
- good volumetric and energy parameters;
- small weight and size;
- perfect design;
- excellent interchangeability of units/ frequently required parts;
- work on several refrigerants;
- excellent indicators of the pressure ratio in one compression stage.
Cons:
- poor structural balance;
- low reliability;
- the presence of friction pairs;
- the possibility of the release of lubricating oil;
- pulsation of flows in pipelines.
Rotary compressors
The operation of rotary compressors is based on the compression of the refrigerant and its movement through the pipes due to the rotation of the working bodies (plates, screws, Industrial Washers, spirals).
Pros:
- compact overall dimensions;
- no valves;
- reduced starting current;
- small pressure pulsations;
- low noise level.
Cons:
- short service life;
- the complexity of repair and installation;
- loss of productivity due to the formation of carbon deposits on the blades;
- small feed rate;
- often fails causing the fridge stops running.
Linear compressors
Linear compressors are based on reciprocating piston movements. Thanks to their design, it is possible to significantly reduce the noise level of the compressor and reduce energy consumption by up to 45%.
Pros:
- environmental friendliness;
- efficiency;
- low noise and vibration level;
- extended service life compared to the traditional ones.
Cons:
- frequent starts and stops of the compressor;
- heavy loads.
Inverter compressor control technologies are beginning to be adopted by most manufacturers. This technology allows to quickly cool the air in the refrigeration compartment to the required level. When it is achieved the compressor will reduce the speed to a minimum but not turn off. This minimum will maintain the temperature at the same level.
In the case of traditional compressors, when the temperature drops, they work at maximum and turn off when the required temperature is obtained. Due to such shutdowns and starts, temperature fluctuations occur, and this negatively affects the shelf life of products. Also, inverter technology made it possible to reduce the energy consumption of the refrigerator, reduce the noise level and increase the life of the compressor.