Maintenance of evaporator

1. Carry out leakage detection of evaporator frequently. Leakage is a common fault phenomenon of evaporator, and it should be checked frequently during use.

When the ammonia evaporator leaks, there is a pungent smell, and there is no frost at the leakage point. The leakage can be checked with phenolphthalein test paper, because ammonia is alkaline and turns red when encountering phenolphthalein test paper. When you look with your eyes, the place where there is no frost in the evaporator is usually the leak point. You can also use soapy water to find the leak at the leak point.

Halogen lamp and halogen leak detector can be used to check the leakage of Freon evaporator, or soap water can be used to find the leakage. When checking, you can check whether there is oil stain on the evaporative drain pipe with eyes first, because Freon and oil are mutually soluble, and when Freon leaks, oil will also leak out from the leak point, so where there is oil stain, there will be leakage. When the halogen lamp is used for leak detection, if there is a Freon leak somewhere, the flame of the halogen lamp will change from blue to light green, light green, grass green, purple green, purple and other colors to judge the amount of Freon leak. If the flame is dark green or purple, the phosgene in the flame is toxic and cannot be checked with this method for a long time. In this case, the leak point can be checked with soapy water. For minor leakage, halogen leak detector shall be used for leakage detection.

2. Check the frosting condition of evaporator frequently. When the frost layer is too thick, defrost it in time. In case of abnormal frosting, it may be caused by blockage, and the cause shall be found and eliminated in time.

3. When the evaporator is out of service for a long time, put the refrigerant into the liquid receiver or condenser to keep the pressure of the evaporator at about 0.05MPa (gauge pressure). If it is the evaporator in the brine tank, it shall be flushed with tap water, and the tank shall be filled with tap water after flushing.