Uneven Dust Accumulation on Condenser Fans Causes Various Imbalances on the Refrigerant Side

1. Uneven distribution of airflow for heat dissipation, resulting in a significant temperature difference across a single condenser

Localized dust accumulation in the fan blocks the air duct, preventing airflow through some heat exchange fins while causing excessive airflow in other areas; this leads to a polarized heat dissipation capacity across the condenser surface.

In areas with poor heat dissipation, the refrigerant does not cool sufficiently, and the subcooling of the liquid refrigerant drops significantly; while in areas with adequate airflow, the refrigerant is overcooled.

Uneven cooling of the refrigerant within the same circuit causes imbalances in internal pressure and flow rate, leading to gas-liquid phase separation and an overall decline in heat transfer efficiency.

2. Persistently High and Fluctuating System High-Pressure, with Frequent Compressor Load Adjustments

Heat dissipation is obstructed at dust-clogged locations, preventing the refrigerant from fully condensing and causing the discharge pressure to rise; the clean areas of the fan briefly remove heat, causing the pressure to drop slightly.

High-pressure levels continue to fluctuate, causing the unit’s protection logic to repeatedly adjust compressor load and cycle the auxiliary heater on and off; prolonged variable-load operation of the compressor increases wear and tear and is likely to trigger a high-pressure alarm shutdown.

3. Refrigerant flow imbalance, localized liquid accumulation in piping, and oil return imbalance

Heat dissipation varies across the condenser’s multiple flow paths, resulting in different refrigerant condensation rates: branches with poor heat dissipation have more gaseous refrigerant and higher flow rates; while branches with good ventilation experience significant accumulation of liquid refrigerant.

Liquid refrigerant accumulates in localized heat exchange piping, diluting the lubricating oil returning to the compressor and reducing its effectiveness, which leads to increased internal wear on the compressor.

Poor oil return can result in oil accumulation in the oil separator and high temperatures in the cylinder due to oil starvation.

4. Uneven thermal stress, resulting in fatigue leaks at fins and weld joints

Localized fins are exposed to high temperatures for extended periods, while other areas remain cooler, creating a significant overall temperature difference across the condenser. The repeated expansion and contraction of the fins and copper tube weld joints generate fatigue stress.

Prolonged operation can lead to micro-leaks, causing a slow refrigerant leak; once the refrigerant level becomes insufficient, the evaporation temperature spirals out of control, disrupting both the vacuum and material temperature.

5. Imbalance in expansion valve flow, overloading of the evaporation-side heat exchange

The condenser outlet liquid temperature fluctuates wildly, causing the refrigerant temperature entering the expansion valve to be unstable, which in turn causes the valve to frequently adjust its opening.

The refrigerant supply fluctuates wildly, causing the heat exchange load on the plate evaporator to fluctuate dramatically. This results in continuous fluctuations in feed temperature and steam production, as well as significant oscillations in vacuum tracking. Concurrently, issues such as foam carrying feed and scaling worsen.

6. Unbalanced fan load, combined with secondary motor failures and deteriorating refrigerant quality

Heavy dust accumulation on one side creates high air resistance, causing uneven stress on the fan blades and intensifying vibration; this vibration is transmitted to the condenser piping, accelerating cracks in the copper tube welds and resulting in refrigerant leaks.