The high-pressure failure of the chiller means that the compressor discharge pressure is too high, which causes the high-pressure protection relay to operate. The compressor discharge pressure reflects the condensing pressure, the normal value should be 1.4~1.8MPa, and the protection value setting is recommended not to exceed 2.0MPa. Because the long-term pressure is too high, it will cause the compressor to run too much current, easily burn the motor, and cause damage to the compressor. So what is the main cause of high pressure failure? How to solve it?

1. Excessive refrigerant charge. This situation generally occurs after maintenance, and it is manifested as high suction and discharge pressure and balance pressure, and the compressor operating current is also high.

Solution: The refrigerant should be discharged according to the suction and discharge pressure and the balance pressure and the operating current under the rated conditions until it is normal.

2. The cooling water temperature is too high and the condensing effect is poor. The rated working conditions of the cooling water required by the chiller are between 30 and 35. High water temperature and poor heat dissipation will inevitably lead to high condensing pressure. This phenomenon often occurs in high temperature seasons.

Solution: The reason for the high water temperature may be the failure of the cooling tower, such as the fan is not turned on or even reversed, the water distributor does not turn, it is manifested as the cooling water temperature is very high, and it rises rapidly; the outside temperature is high, the water path is short, and it can be circulated In this case, the cooling water temperature is generally maintained at a relatively high level, which can be solved by increasing the storage tank.

3. The cooling water flow is insufficient, and the rated water flow cannot be reached. 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's operation), and the temperature difference becomes larger.

Solution: The pipeline filter is clogged or the selection is too fine, and the water permeability is limited. Choose a suitable filter and clean the filter regularly; or the water pump is small and does not match the system.

4. The condenser is fouled or blocked. Condensate water generally uses tap water, it is easy to scale when it is above 30, and because the cooling tower is open, it is directly exposed to the air, dust and foreign matter can easily enter the cooling water system, causing the condenser to be dirty and blocking, 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 upper and lower temperatures of the condenser are very high when the condenser is touched by hand, and the condenser outlet copper pipe is hot.

Solution: The unit should be backwashed regularly, and chemical cleaning and descaling should be carried out if necessary.

5. False alarms caused by electrical faults. Because the high-voltage protection relay is damp, poorly contacted or damaged, the unit electronic board is damp or damaged, and the communication failure causes a false alarm.

Solution: For this kind of false fault, the HP fault indicator on the electronic board is often off or slightly bright, and the manual reset of the high-pressure protection relay is invalid. The running current of the compressor is normal, and the suction and exhaust pressures are also normal.

6. The refrigerant is mixed with non-condensable gases such as air and nitrogen. There is air in the refrigeration system. In many cases, the pointer of the high-pressure meter will vibrate severely when there is a lot of air.

Solution: This situation generally occurs after maintenance, and the vacuum is not complete. It can be evacuated at the highest point of the condenser after shutdown or re-evacuated to add refrigerant.

If your water chiller machine has a high-pressure alarm, you can check according to the article. Or you can contact the water chiller factory to help you solve it. Need to know the details of our water chiller machine, please visit the products page.