What is a Chiller Plant Used For?
A chiller can be regarded a cooling system that cools materials down by removing heat from a liquid via a vapor-compression or absorption refrigeration cycle. The liquid gets circulated through a heat exchanger to cool equipment. In a chiller system, there is always a liquid working as a refrigerant going through the heat exchanger in order to transfer the heat energy. When the heat gets absorbed by the liquid, materials get chilled.
What are the Chiller Plant Problems?
- Reduced compressor speed reduces exhaust volume.
- The impact of the problemsof the compressor suction and exhaust valves on the displacement.
- Insufficient refrigerant charge in the system.
- The filter at the expansion valve mouth is blocked, and the liquid supply in the evaporator is insufficient.
What Would Cause a Chiller to Surge?
Generally, chiller surge doesn’t occur under normal circumstances. But if there is a pressure difference between the outlet and inlet of the compressor, a chiller may be caused to surge. Because of this large pressure, the refrigerant may tend to flow back against the compressor. The compressor components may be damaged, and the normal cycle may be disrupted. So how to avoid this situation? The certain temperature and pressure measuring devices can be used with the flow meters to monitor conditions so that the chiller surge can be avoided.
How do you Check a Chiller Leakage?
To determine the leakage method, you can check the return air pressure of the compressor when the chiller is running. If it is lower than the normal value, there may be a leakage. In addition, it is also possible to detect the running current with an ammeter. If the current is significantly lower than the normal value, it can also be determined that the system has leaked. Another more intuitive and convenient method is to observe the evaporator: the low-pressure pressure drop caused by refrigerant leakage, the frost tendency of the chiller evaporator is increased, and unreasonable frost may occur (such as above 10 ℃ frost).
What Would Cause Low Evaporator Temperature on a Chiller?
There are three reasons leading to low evaporator temperature on a chiller:
- The scale of evaporator is too small. There is a problem about design, or the actual storage type is different from the planned storage type, and the heat load increases.
- Evaporator did not defrost in time. The frosting of the evaporator coil reduces the heat transfer coefficient, increases the thermal resistance, reduces the heat transfer effect, and reduces the amount of refrigerant evaporation. When the compressor energy is absolute, the evaporation temperature decreases.
- There is lubricating oil in the evaporator. The lubricating oil in the evaporator will form an oil film on the tube wall of the evaporation coil, which will cause the evaporation pressure of the system to decrease and the corresponding evaporation temperature to decrease.
What Would Cause Low Evaporator Pressure on a Chiller?
When the season changes, the ambient temperature changes, and its condensing temperature and pressure will change, so that the refrigeration system operates under the changing condensing pressure, which is not conducive to the operation of the compressor, and it often fails during operation. In order to prevent such failures, the refrigeration devices (including air conditioners) with an energy of more than 20,000W that need to be operated in winter should be equipped with a condensing pressure regulating valve to maintain a constant condensing pressure and maintain the stable operation of the compressor.