Briefly explain the operating requirements of the chiller

For a running chiller. Environmental conditions, the load has become a fixed value At this time, the condensing heat load is also a fixed value. 

It is stipulated that the temperature difference between the inlet and outlet water is 5 °C, the cooling water volume must also be a certain value, and the flow is inversely proportional to the temperature difference between the inlet and outlet water. Therefore, the operation of the chiller. As long as the temperature difference between the inlet and outlet of the cooling water is specified, the flow is usually controlled by the pressure drop of the cooling water entering and leaving the condenser. Under standard operating conditions, the pressure drop of the inlet and outlet water of the condenser is set to 68.6 kPa (0.7kg/cm: ).

In the actual operation of the cooling water system, there are often the following misoperations:

(1) Before starting the machine, the water inlet valve of the condenser on the unit that does not need to be opened is not closed, resulting in water blowing. A part of the cooling return water flows away from the condenser of the non-operating unit, which reduces the cooling water flow in the condenser of the running unit, causing the condensing pressure to rise. The operating current of the host increases. The cooling capacity of the unit decreases, which will seriously cause the unit to Stop running. It not only wastes electricity, but also reduces the cooling effect, and it is easy to damage the equipment.
(2) Due to the misoperation of the previous item, the condensing pressure of the host and the temperature of the cooling water outlet increased. Misjudgment is caused to the operator. It is mistaken for the insufficient cooling water to open the inlet valve of the condenser and the outlet valve of the cooling water pump, and some also increase the cooling tower fan, causing the power consumption of the water pump and cooling tower fan to increase.
⑶ What's more, blindly add a cooling water pump. Although adding a cooling water pump can indeed reduce the cooling water temperature and condensing pressure, after all, the electric energy of a water pump is wasted in vain. Therefore, the correct operation method of adding a wrong cooling water system is:
⑴Before starting the machine, the water inlet valve of the condenser of the unit does not need to be closed to prevent water blowing.
(2) Open the inlet and outlet valves on the condenser of the unit to be operated (generally, the outlet valve is normally open, and the inlet valve is opened and closed as required. The condenser and evaporator are the same), and the corresponding cooling water pump is turned on. Adjust the pressure drop of the inlet and outlet water of the condenser To about 68.6kPa (0.7 kg/cm:) (the pressure drop is based on the principle of overcoming the resistance of the pipeline. The lower the power saving effect is better).
⑶ If the pointer of the inlet and outlet water pressure gauge of the condenser swings too much, it means that there is air in the cooling water system. It is necessary to exhaust the air and continue the next operation after the pressure gauge indicates normal.
⑷ In operation, no matter how many units are opened, it is one cooling water pump to one main engine (the matching should be the same).