High pressure failure and treatment measures in chiller system
1.The cooling water temperature is high and the condensation effect is poor. The cooling water required by the chiller is rated at 30~35°C, the water temperature is high, and the heat dissipation is poor, which inevitably leads to high condensing pressure. This phenomenon often occurs in the hot season. Caused by the high water temperature may be: cooling tower failure, such as the fan is not open or even reversed, the water distributor does not turn, the performance of the cooling water temperature is high, and rapid increase; outside temperature is high, the water is short, the amount of water can be recycled Less, in this case, the cooling water temperature is generally maintained at a relatively high level and can be solved by adding reservoirs.
2. Insufficient cooling water flow cannot reach rated water flow. The main performance is that the pressure difference between the inlet and outlet 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 the lack of water flow is the lack of water or air in the system. The solution is to install an exhaust valve at the height of the pipeline to vent the air; the filter of the pipeline is blocked or selected too thin, and the water permeability is limited. The appropriate filter should be used. Clean the filter regularly; the pump is small and not compatible with the system.
3. condenser fouling or plugging. The condensate water is usually tap water, and it is easy to foul at temperatures above 30°C. Because the cooling tower is open, it is directly exposed to the air. Dust foreign materials can easily enter the cooling water system, causing the condenser to become dirty and the heat transfer area is small. The efficiency is low, but it also affects the water flow. Its performance is that the pressure difference between the water inlet and outlet of the unit, the temperature difference becomes larger, the upper and lower temperatures of the condenser are very high by hand, and the condenser liquid copper pipe is hot. The unit should be backwashed on a regular basis and, if necessary, chemically cleaned.
4. Excessive refrigerant charge. This situation usually occurs after maintenance, and the performance of suction and exhaust pressure and balance pressure are high, and the compressor operating current is also high. The gas shall be deflated according to the suction and discharge pressures and the equilibrium pressure and the operating current under normal conditions until normal.
5. The refrigerant contains air, nitrogen, and other non-condensing gases. This situation generally occurs after maintenance, vacuum is not completely exhausted. Only drain, re-vacuum, refill refrigerant.
6. False alarms caused by electrical faults. Due to moisture, poor contact or damage of the high-voltage protection relay, the electronic board of the unit is damped or damaged, and communication failures cause false alarms. This kind of spurious failure, often the HP failure indicator on the electronic board is not bright or bright, the manual reset of the high voltage protection relay is invalid, the computer displays “HPRESET”, or disappears automatically, the compressor running current is normal, and the suction and discharge pressure is also normal. .