The compressor of Xinfei refrigerator is running, but it does not cool.
Analysis and Maintenance: This machine has been in use for 5 years. Recently, due to poor cooling effect, it gradually developed into no cooling at all. It was suspected that the low efficiency of the compressor caused the refrigerant in the system to leak or be blocked. After powering on and testing the machine, the working current of the refrigerator was measured with a clamp ammeter, which was normal, indicating that there was no blockage in the system. However, the condenser was not hot and the evaporator did not frost up. After stopping the machine and disconnecting the process pipe of the compressor, a large amount of refrigerant gas sprayed out, indicating that the refrigerant had not leaked. Then, the suction and exhaust pipes of the compressor were welded open, and the compressor was powered on and run, and it was found that its suction and exhaust were normal, indicating that the working efficiency of the compressor was also normal. Based on the above inspection, it was determined that the evaporator was faulty. The evaporator of this refrigerator is an aluminum plate printed pipeline blow-up type evaporator. After removing the evaporator and pressurizing it to 0.5MPa for testing, it was found that the channel of the evaporator was torn apart, causing channel mixing, resulting in the refrigerant throttled by the capillary tube entering the evaporator and unable to fully absorb heat and evaporate, causing the no-cooling fault.
Handling method: Replace the evaporator, restore the pipeline, check for leaks, evacuate, charge the refrigerant, and test the machine. The fault was eliminated.
Fault phenomenon: The compressor is running, but it does not cool.
Maintenance tips: The evaporator is the cooling component of the refrigerator cooling system. Its function is to make the gas-liquid mixture of the refrigerant after throttling absorb the heat inside the box and quickly boil and vaporize into dry saturated steam, thereby reducing the temperature inside the box. The lower the evaporation temperature of the refrigerant in the evaporator, the greater the ability to cool objects, and it works in conjunction with the cold production of the compressor to achieve freezing and refrigeration purposes. There are two types of cooling methods for evaporators: natural convection and forced convection. Direct-cooling refrigerators use natural convection, while indirect-cooling refrigerators use forced convection, i.e., a small fan of less than 10W is equipped inside the box to force the air inside the box to circulate using the wind power of the fan.
Article source: Beijing Xinfei Refrigerator Repair http://blog.tianya.cn/blogger/blog_main.asp?BlogID=3466947.