Jäähdytyshoveri

Jäähdytyshoveri, also known as cooling hover or frost hover, is a phenomenon observed in certain refrigeration systems, particularly those employing vapor-compression cycles. It refers to a condition where the refrigerant in the evaporator coil experiences a temperature drop that causes it to briefly transition from a gaseous state to a liquid state, or even solidify into ice, before it is fully evaporated. This rapid cooling and potential phase change occurs due to specific thermodynamic conditions within the evaporator.

The primary cause of jäähdytyshoveri is an insufficient amount of heat being absorbed by the refrigerant in the evaporator. This can be due to several factors, including low airflow across the evaporator fins, a depleted charge of refrigerant, or a malfunctioning expansion valve that is not properly metering the refrigerant flow. When the refrigerant does not receive enough heat, its temperature can fall below its saturation point, leading to condensation or even ice formation.

While some degree of subcooling is expected and even beneficial for system efficiency, excessive jäähdytyshoveri can lead to operational problems. Ice formation on evaporator coils can restrict airflow, reduce heat transfer efficiency, and potentially damage the equipment due to expansion. In some cases, liquid refrigerant may return to the compressor, which can cause "liquid slugging" and severe compressor damage. Diagnosing and addressing the root cause of excessive jäähdytyshoveri is crucial for maintaining the performance and longevity of refrigeration systems.