What is the impact of the outlet temperature of the chilled water for a 100 ton chiller?

　　What is the impact of the outlet temperature of the chilled water for a 100 ton chiller?

　　We often talk about the cooling capacity of a 100 ton chiller. In fact, the nominal cooling capacity of a 100 ton chiller refers to the cooling capacity at an ambient temperature of 35 ° C and a chilled water outlet temperature of 7 ° C.

　　During the actual operation of a 100 ton chiller, due to the difference between ambient temperature and chilled water outlet temperature, the cooling capacity of the 100 ton chiller and the power consumption of the compressor will also change. Whether it is an air-cooled 100 ton chiller or a water-cooled 100 ton chiller, its cooling capacity increases with the increase of the chilled water outlet temperature and decreases with the increase of the ambient air inlet temperature.

　　Why did this happen? This is because as the outlet temperature of the chilled water increases, the evaporation pressure of the corresponding 100 ton chiller unit increases, the suction specific volume decreases, and the refrigeration capacity per unit volume and 100 ton chiller unit increase; When the ambient temperature increases, the condensation pressure in the refrigeration system of the 100 ton chiller unit increases.

　　Due to the constant evaporation temperature and suction specific volume, the gas transmission coefficient of the chiller compressor decreases and the unit mass cooling capacity decreases. Therefore, the cooling capacity of the 100 ton chiller unit has also decreased.

　　The power consumption of a 100 ton chiller unit will increase with the increase of chilled water outlet temperature and ambient temperature. This is because as the temperature of the chilled water in the cooler increases, the evaporation pressure increases. If the ambient temperature remains constant (i.e. the condensation pressure remains constant), the compression ratio decreases and the power consumption decreases. However, at this point, the power required to increase the cooling capacity of the 100 ton chiller is greater, so the total power consumption of the compressor still increases.

　　If the ambient temperature increases, the condensation pressure increases, and the outlet temperature of the chilled water of the 100 ton chiller remains unchanged (i.e. the evaporation pressure remains unchanged), the compression ratio increases and the power consumption increases. As a result, the required power due to the reduced cooling capacity slightly decreases, but the total power consumption of the compressor still increases.

　　The impact of high outlet temperature of the condenser

　　1. Affects the operational efficiency of the entire machine;

　　The lower the outlet temperature (or saturation temperature) of the condenser, the higher the overall operating efficiency of the system. Therefore, if the outlet temperature is too high, it will affect the operating efficiency of the entire machine;

　　2. Surge or overcurrent protection

　　The higher the outlet temperature of the condenser, the higher the condensation saturation pressure. For the centrifuge, the operating pressure ratio will also increase, which may trigger surge protection; In addition, due to the increase in condensation pressure, the working conditions also become worse. If the user’s load is high at this time, it may also lead to high operating power or current.

　　3. The condenser is more prone to scaling

　　Under high temperature conditions, copper pipes are more prone to scaling, which affects heat transfer performance.

　　4. High voltage protection

　　The higher the outlet temperature of the condenser, the higher the pressure of the condenser; We know that the condenser belongs to a container and has a certain safety design range. Therefore, the unit will set a safety protection value to protect the condenser. Once the safety margin value is exceeded, the unit will alarm and shut down.