What are the causes of abnormal noise in a car's expansion valve?
1 Answers
Abnormal noise from a car's expansion valve indicates a blockage in the valve. 1. Causes of blockage: Blockage faults in the thermal expansion valve of the refrigeration system are common, including "dirt blockage" and "ice blockage." The main cause of dirt blockage is the presence of impurities in the system, such as welding slag, copper chips, iron filings, fibers, etc. Ice blockage occurs when there is excessive moisture in the system. 2. Moisture pathways: During installation, insufficient vacuuming time fails to remove all moisture from the pipelines; poor welding techniques at pipeline connections result in air leakage points. When charging the system with refrigerant, the air in the connecting hoses is not purged. Additionally, air can enter when replenishing the system with lubricating oil.