How to Determine if the Expansion Valve is Faulty?

[KimberlyLynn]

Signs of a faulty expansion valve: 1. The low-pressure pipe is not cold to the touch; 2. Frost forms on the dryer bottle; 3. Frost forms on the condenser; 4. A hissing sound is heard when the expansion valve or condenser is not operating; 5. Abnormal high and low pressure levels and abnormal temperature in the high-pressure pipe. Relevant information about the expansion valve is as follows: 1. Location of the expansion valve: The expansion valve is an important component in the refrigeration system, typically installed between the liquid reservoir and the evaporator. 2. Working principle of the expansion valve: The expansion valve converts medium-temperature, high-pressure liquid refrigerant into low-temperature, low-pressure wet steam through throttling. The refrigerant then absorbs heat in the evaporator to achieve the cooling effect. The valve flow is controlled by changes in superheat at the end of the evaporator to prevent insufficient utilization of the evaporator surface and knocking phenomena.