What Is The Principle Behind The Refrigeration and Dehumidification of Wine Cellar Air Conditioning?

What is the principle behind the refrigeration and dehumidification of wine cellar air conditioning?

Refrigeration is the core mechanism for maintaining a constant temperature of 12°C to 18°C. It relies on the cyclic operation of four major components: the compressor, evaporator, condenser, and throttling device. The process involves four specific steps:

Throttling and Pressure Reduction: High-pressure liquid refrigerant (e.g., R410A) passes through the throttling component (expansion valve), causing a sudden pressure drop. It transforms into a low-temperature (approximately 5°C), low-pressure mist-like liquid and enters the evaporator of the indoor unit.

Heat Absorption and Evaporation: Warm air from the wine cellar is drawn into the evaporator by a fan, where it contacts the low-temperature refrigerant. The refrigerant absorbs heat from the air, evaporating from liquid to gas form, thereby lowering the air temperature to the target range of 12°C to 18°C.

Compression and heating: The gaseous refrigerant is drawn into the compressor, where it is compressed into a high-temperature (approximately 80°C) high-pressure gas. It is then sent to the condenser in the outdoor unit.

Heat dissipation and liquefaction: The outdoor unit's fan circulates air over the condenser. The high-temperature gaseous refrigerant transfers its heat to the outdoor air, cooling itself and liquefying back into a high-pressure liquid. It then flows back to the throttling device to begin the next cycle.

Through this continuous cycle, heat within the wine cellar is constantly transferred outdoors, maintaining a stable low-temperature environment.

The dehumidification function of wine cellar air conditioning is not an independent system but leverages the “condensation water separation” phenomenon during refrigeration. It operates through three key stages:

Cooling to Dew Point: When humidity exceeds thresholds (e.g., above 75% RH), the controller adjusts the refrigeration system. As warm, humid air passes over the evaporator, its temperature rapidly drops below the “dew point temperature” (the critical temperature where water vapor condenses into liquid water, typically 3°C–5°C below the target temperature).

Condensation and Water Separation: Once temperatures fall below the dew point, water vapor in the air condenses into liquid droplets on the evaporator surface. These droplets collect in a drip pan beneath the evaporator.

Drainage Processing: Condensate from the drip pan is discharged from the wine cellar via drain pipes (some models feature drain pumps to elevate water discharge, e.g., to outdoor sewers). This process reduces atmospheric moisture content, achieving dehumidification.

Note that wine cellar air conditioners regulate dehumidification by controlling refrigeration runtime—higher humidity requires longer cooling cycles for greater moisture removal. When humidity reaches the target range (e.g., 55%-75% RH), refrigeration pauses or reduces power to prevent excessive dehumidification.