What happens if the expansion valve is damaged?

[Reed]

The consequences of a damaged expansion valve are: 1. Insufficient liquid supply, resulting in reduced refrigerant flow; 2. Excessive liquid supply, causing liquid backflow into the compressor, with low superheat and normal or slightly high suction pressure; 3. During compressor startup, a large refrigerant flow rate may allow liquid to enter the compressor, with no superheat and suction pressure higher than normal; 4. Fluctuating liquid supply due to incorrect expansion valve selection, leading to refrigeration system oscillation or intermittent instability. The expansion valve is a critical component in the refrigeration system, typically installed between the liquid receiver and the evaporator. It converts medium-temperature, high-pressure liquid refrigerant into low-temperature, low-pressure wet vapor through throttling. The refrigerant then absorbs heat in the evaporator to achieve cooling. The expansion valve controls the flow rate based on superheat changes at the evaporator outlet, preventing insufficient evaporator area utilization and compressor slugging. Ideally, the expansion valve should adjust its opening in real-time according to evaporator load changes to control the flow rate.

[MilesDella]

A faulty expansion valve can be a real headache, and I've experienced this issue firsthand. The expansion valve is a small component in the air conditioning system that regulates refrigerant flow. If it gets clogged or leaks, the refrigerant can't circulate properly or becomes imbalanced. As a result, the AC either stops cooling or provides uneven cooling, blowing warm air from the vents—especially unbearable during summer drives. Even worse, the compressor pressure rises, forcing it to operate under continuous high load, which can eventually lead to burnout and significantly higher repair costs. I once inspected a car where a stuck expansion valve caused the evaporator to freeze up, damaging the pipes as well. In such cases, it's best not to delay—visit a professional repair shop to check the valve's condition and clean the entire AC circuit to prevent further issues.

[SanTalia]

The recent issue with my car's air conditioning was caused by a faulty expansion valve. The symptoms were quite obvious: normal airflow but no cold air, the interior temperature wouldn't drop, and driving long distances in summer left me sweating profusely. Moreover, fuel consumption noticeably increased because the compressor was constantly working hard. After inspection at the repair shop, the mechanic said the expansion valve had failed, causing uncontrolled refrigerant flow. The fix was simple—replacing the expansion valve restored everything to normal. Although small, the expansion valve plays a crucial role by converting liquid refrigerant into a fine spray to help the evaporator cool the air. If it leaks or gets blocked, the entire cooling process collapses. I recommend paying close attention to your AC's performance and addressing any issues promptly without delay.

[Catherine]

A faulty expansion valve is no joke and can lead to serious safety issues. When the air conditioning system fails, the stuffy heat inside the car can easily cause heatstroke, and driver fatigue affects concentration, multiplying risks on highways or in hot weather. A damaged expansion valve disrupts the refrigerant circuit, causing erratic pressure in the pipes that may lead to leaks or strange noises, and in extreme cases, even fire hazards. I always emphasize not to overlook these small components—regularly maintain the AC system, keep the valve clear, and seek professional inspection at the first sign of insufficient cooling. Safety should always come first, with no compromises.