Many users will find that the chiller is insufficient in the process of using the chiller. At the beginning, it can be cooled down and run for a period of time. It is found that the temperature cannot be reduced. Xiaobian today uses three methods to determine whether the refrigerant is insufficient and then look for other reasons .
1. Current method: Use clamp ammeter to monitor the working current of outdoor unit (including compressor and fan current). If the current value basically meets the rated current on the nameplate, it means that the refrigerant is suitable; if it is lower than the rated value, the refrigeration is appropriate. Too little agent needs to be added.
2. Gauge pressure method: The pressure on the low-pressure side of the refrigeration system is related to the amount of refrigerant. Connect the pressure gauge to the low-pressure valve, the air conditioner starts cooling, and the gauge pressure will drop at the beginning. After more than 10 minutes of operation, it is normal if the gauge pressure stabilizes at about 0.49Mpa.
3. Observation method: observe the dew on the high-pressure pipe near the high-pressure valve of the outdoor unit and the low-pressure pipe near the low-pressure valve. Generally, the high-pressure pipe is dew condensation, and it is cold. If the low-pressure pipe is also dew condensation, it has a cool feeling, and the temperature is about 3 ° C higher than that of the high-pressure pipe, indicating that the refrigerant is suitable. If the low-pressure tube does not dew and has a warm feeling, it means that the amount of refrigerant is insufficient and it needs to be added; Excessive refrigerant needs to be drained.
The above three methods are mainly based on current measurement and observation of high-pressure and low-pressure tube condensation, and gauge pressure method is also used to determine whether to add refrigerant. It should be noted that when the air conditioner is cooling, the outdoor fan must be turned on, otherwise the cold air around the evaporator is not dispersed in time, which will cause the evaporation temperature to drop and the evaporation pressure to fall. The gauge pressure read is too small and the current is too small, causing Misjudgment.