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Why Your Chiller Unit Operating Cost Is So High?

Aug 02, 2017

Why your chiller unit operating cost is so high?

Chiller unit, how much cooling capacity, and the system operating conditions are directly related to the same structure, speed, refrigerant types have been identified compressor, due to changes in operating conditions, different operation and management, its cooling capacity and energy consumption Also with change.

1, with the evaporation temperature decreases, the compressor compression ratio increases, the unit cooling capacity increased energy consumption. When the evaporation temperature for each lower 1 ℃, you have to consume 3% -4%. So as far as possible to reduce the evaporative temperature difference, improve the evaporation temperature, not only save power consumption, but also can improve the cold relative humidity.

2, with the condensing temperature increases, the compressor compression ratio increases, the unit cooling capacity of the increase in energy consumption. Condensation temperature between 25 ℃ -40 ℃, each increased 1 ℃, increased power consumption of about 3.2%.

3, the condenser and evaporator heat transfer surface covered with oil layer, will cause the condensation temperature, evaporation temperature decreases, resulting in reduced cooling capacity and increased power consumption. Condenser on the surface with 0.1mm thick oil layer, the compressor will reduce the cooling capacity of 16.6, power consumption increased by 12.4; evaporator on the surface of oil 0.1mm thick oil layer, in order to maintain the already set low temperature requirements, The evaporation temperature drops by 2.5 ° C and the power consumption increases by 9.7.

4, when the air gathered in the condenser, will cause the condensing pressure increases, non-condensing gas sub-pressure reached 1.96105Pa, the compressor power consumption should be increased by 18.

5, when the condenser pipe wall junction scale to 1.5mm, the condensation temperature than the temperature before the rise of 2.8 ℃, power consumption increased by 9.7.

6, the evaporator surface covered with a layer of frost, so that the heat transfer coefficient decreases, especially the outer surface of the fin tube frost, not only increased the heat transfer resistance, but also to the air between the fins difficult to reduce the appearance Of the heat transfer coefficient and heat dissipation area. When the indoor temperature is below 0 ℃, the evaporator tube group on both sides of the temperature difference of 10 ℃, the evaporator work for a month, the heat transfer coefficient is about 70 before frost.

7, the compressor inhaled gas allows a certain degree of superheat, but the superheat is too large, the specific volume of the inhaled gas increases, the cooling capacity is reduced, the relative increase in power consumption.

8, the compressor to the cream, quickly shut the small suction valve, a sharp reduction in cooling capacity, the relative increase in power consumption.

Through the above analysis we can see that the operation of refrigeration equipment management, is to improve the economic efficiency of the refrigeration system an important part.

Energy saving measures for cooling operation

Strengthen the operation and management of equipment, the establishment of electricity management and consumption statistics system. Easy to assess the consumption of electricity and material consumption quota, increase the necessary measurement instruments and apparatus, carry out energy conservation and technological transformation work, from the system to consolidate energy conservation work down.

1, the correct control and regulation of the system for the amount of liquid, and to avoid the compressor suction too wet and overheating phenomenon.

2, a reasonable choice of the number of compressor operating table, so that the cooling capacity and the system to match the heat load.

3, according to process requirements and changes in external temperature, the appropriate adjustment of the number of fans and pumps running.

4, regular oil, put the air, defrost and remove the scale, to maintain good heat transfer effect of equipment to avoid excessive condensation pressure and evaporation pressure is too low.

As much as possible to improve the working conditions of refrigeration equipment

1, to improve water quality, slow down the scaling, improve the condensation effect of the condenser, reduce the condensation temperature.

2, the cooling equipment motor load rate of 0.4 or less, the motor can be changed from △ to Y connection to improve the power factor, and requires △ and Y connection can automatically switch.

3. As far as possible using automatic control operation instead of manual operation, you can achieve the best operating conditions in the refrigeration system, so you can save 5-15%.