(1) The cooling water temperature is too high and the condensation effect is poor.

The cooling water required by the chiller is rated at 30~35°C. The high water temperature and poor heat dissipation will inevitably lead to high condensing pressure. This phenomenon often occurs in high temperature seasons. The reason for the high water temperature may be: the cooling tower is faulty, such as the fan is not turned on or even reversed, and the water distributor does not turn. The performance is that the temperature of the cooling water is very high, and it rises rapidly, the outside air temperature is high, the water circuit is short, and the amount of water that can be circulated is small.

(2) The cooling water flow is insufficient and cannot reach the rated water flow.

The main performance is that the pressure difference between the inlet and outlet water of the unit becomes smaller (compared with the pressure difference at the beginning of the system operation), and the temperature difference becomes larger. The reason for insufficient water flow is the lack of water or the presence of air in the system. The solution is to install an exhaust valve at the height of the pipeline to exhaust; the pipeline filter is blocked or too thin, and the water permeability is limited. Clean the filter screen regularly; the water pump is small and not matched with the system.

(3) The condenser is fouled or blocked.

Tap water is generally used for condensed water, and it is easy to scale when the temperature is above 30 °C, and because the cooling tower is open and directly exposed to the air, dust and foreign matter can easily enter the cooling water system, causing the condenser to be dirty and blocked, and the heat exchange area is small. , the efficiency is low, and it also affects the water flow. The performance is that the pressure difference and temperature difference between the inlet and outlet water of the unit become larger, the temperature of the upper and lower condensers is very high, and the copper pipe of the condenser is hot. The unit should be backwashed regularly, and chemical cleaning and descaling should be carried out if necessary.

(4) The refrigerant is charged too much.

This situation generally occurs after maintenance, and it is manifested as high suction and exhaust pressure, balance pressure, and high compressor operating current. It should be deflated according to the suction and discharge pressure and balance pressure and operating current under rated operating conditions until it is normal.

(5) The refrigerant is mixed with non-condensable gases such as air and nitrogen.

This situation generally occurs after maintenance, and the vacuuming is not complete. It can only be drained, re-evacuated, and recharged with refrigerant.

(6) False alarms caused by electrical faults.

Because the high-voltage protection relay is damp, bad contact or damaged, the unit electronic board is damp or damaged, and the communication failure causes false alarms. For this kind of false fault, the HP fault indicator on the electronic board is often not bright or slightly bright, the manual reset of the high-voltage protection relay is invalid, the computer displays “HPRESET”, or disappears automatically, the running current of the compressor is normal, and the suction and exhaust pressure is also normal.