Why is your chiller so power hungry?

The cooling capacity of the chiller is directly related to the operating status of the system. For compressors with the same structure, the same speed, and the same refrigerant type, due to changes in operating conditions, cooling capacity and energy consumption, the operation management is also different, and it also changes accordingly.

1. As the evaporation temperature decreases, the compression ratio of the compressor increases, and the unit energy consumption of production cooling increases. When the evaporation temperature is lowered by 1°C, it consumes 3% to 4%. Therefore, reducing the evaporation temperature difference as much as possible and increasing the evaporation temperature not only saves energy consumption, but also improves the relative humidity of the cold room.

2. With the increase of the condensing temperature, the compression ratio of the compressor increases, and the energy consumption per unit cooling capacity increases. For every 1°C increase in condensing temperature between 25°C and 40°C, power consumption increases by about 3.2%.

3. When the heat exchange surfaces of the condenser and the evaporator are covered with an oil layer, the condensation temperature increases and the evaporation temperature decreases, resulting in a decrease in cooling capacity and an increase in power consumption. When a 0.1mm thick oil layer accumulates on the inner surface of the condenser, the cooling capacity of the compressor will decrease by 16.6, and the power consumption will increase by 12.4. When the oil is 0.1 mm thick in the inner surface evaporator, in order to maintain the predetermined low temperature requirement, the evaporation temperature drops by 2.5°C and the power consumption increases by 9.7.

4. When the air gathers in the condenser, the pressure of the condenser will rise. When the partial pressure of the non-condensable gas reaches 1.96105Pa, the power consumption of the compressor needs to be increased by 18.

5. When the scale of the condenser wall reaches 1.5 mm, the condensing temperature rises by 2.8°C before the temperature scaling, and the power consumption increases by 9.7.

6. The surface of the evaporator is covered with a layer of frost, which reduces the heat transfer coefficient. In particular, the outer surface of the finned tube is frosted, which not only increases the heat exchange resistance, but also makes the air flow between the fins difficult and reduces the appearance. Heat transfer coefficient and heat dissipation area. When the indoor temperature is lower than 0°C, when the temperature difference between the two sides of the evaporator tube group is 10°C, the heat transfer coefficient of the evaporator after frosting is about 70 for one month.

7. The gas inhaled by the compressor allows a certain degree of overheating, but if the overheating is too large, the specific volume of the inhaled gas increases, the cooling capacity decreases, and the relative power consumption increases.

8. When the compressor is frosted, the small suction valve is quickly closed, the cooling capacity is sharply reduced, and the power consumption is relatively increased.