Working Principle and Function of Automotive Expansion Valve?

1 Answers
MicahAnn
07/29/25 7:23pm
Automotive expansion valve, also known as throttle valve, is a key component of automotive air conditioning refrigeration systems, serving as the boundary point between high and low pressure in the system. Below are the details: 1. Working principle of automotive expansion valve: The flow of coolant primarily relies on the pressure generated by the water pump. When the suction pressure on the pump's low-pressure side becomes too low, vapor bubbles will form, leading to a decrease in water flow. This condition easily causes cavitation, resulting in surface pitting. Failure to prevent this issue will directly reduce the component's service life. 2. Function of automotive expansion valve: It throttles and reduces the pressure of high-pressure liquid refrigerant from the receiver-drier. It regulates and controls the amount of liquid refrigerant entering the evaporator to adapt to changes in cooling load, while also preventing compressor liquid slugging and abnormal overheating of vapor at the evaporator outlet.
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