The compressor is the “heart” of a refrigerator. It circulates the refrigerant throughout the system, adds pressure to the warm part of the circuit, and makes the refrigerant hot. It’s similar to when you are pumping air into a bicycle tube – you can sense a heat increase in the pump while you compress the air.
The condenser sits on the back of a refrigerator and is likely quite dusty. The refrigerant is cooled down and condenses, turning from a gas back into a liquid inside.
The evaporator is located inside a refrigerator and is the part that makes the items in the refrigerator cold. As the refrigerant turns from a liquid into a gas through evaporation, it cools the area around it, producing the proper environment for storing food.
The capillary tube is a thin piece of tubing that serves as an expansion device. The liquid refrigerant is routed through the capillary tube and sprayed into the low-pressure environment of the evaporator.
The thermostat controls the cooling process by monitoring the temperature and switching the compressor on and off. When the sensor senses that it’s cold enough inside a refrigerator, it turns off the compressor. If it senses too much heat, it switches the compressor on and begins the cooling process again.
Changhong Refrigerator system works.
Refrigerators work by causing the refrigerant circulating inside them to change from a liquid into a gas. This evaporation process cools the surrounding area and produces the desired effect. You can test this process for yourself by taking some alcohol and putting a drop or two on your skin. As it evaporates, you should feel a chilling sensation – the same basic principle gives us safe food storage.
To start the evaporation process and change the refrigerant from liquid to gas, the pressure on the refrigerant needs to be reduced through an outlet called the capillary tube. The effect is similar to using an aerosol product such as hair spray. The contents of an aerosol can are the pressure/liquid side, the outlet is the capillary tube, and the open space is the evaporator. When you release the contents into the lower pressure open space, it turns liquid into a gas.
To keep a refrigerator running, you need to be able to get the gaseous refrigerant back to its liquid state, so the gas needs to be compressed to a higher pressure and temperature again. This is where the compressor comes in. As mentioned earlier, the compressor provides a similar effect to a bike pump. You can sense the heat increase in the pump while you pump and compress the air.
Once the compressor has done its work, the gas should be under high pressure and hot. It needs to be cooled in the condenser, which is mounted on the back of the refrigerator so that the ambient air can cool its contents. When the gas cools off inside the condenser (still under high pressure), it changes back into a liquid.
Then, the liquid refrigerant circulates back to the evaporator, where the process starts again.