How to take anti freezing measures for industrial chillers in winter

In winter, when the ambient temperature is below zero, in order to ensure the smooth winter of the chiller and avoid irreversible losses to the equipment caused by the low temperature environment, it is necessary to take antifreeze measures for the chiller equipment. So, how to take anti freezing measures for industrial chillers in winter?

Since the air-cooled water chiller is installed outdoors, the antifreeze of the air-cooled water chiller is particularly important. Most manufacturers remind users to fill the cold water system with antifreeze during installation. In different regions, as long as a standard amount of antifreeze is filled in the chilled water system according to the local ambient temperature, it is basically safe to spend the winter.

Generally speaking, the treatment of water-cooled chillers will be very high, and they will be served by heating. Even if there is no heating, they will be in the basement or indoors, so there is no need to worry about wintering. But for most brands of centrifugal units, in order to ensure the temperature of lubricating oil, please do not power off.

During the day or night when the pump is not used, the pump must be kept running, and if it is not used for a long time, the water must also be drained. In case of severe weather (temperature below - 10 ℃), it is better to stop the machine and drain water, or add antifreeze to the water.

Here are some drainage measures for chillers in winter:
1. Condenser: open the end cover at the other end of the water connection pipe. After opening, pay attention to put the end cover and screws away. Install the end cover and screws before starting the next year. (Remember: do not do this for evaporator drainage)

2. Evaporator: open the drain valve below the evaporator connecting pipe to drain the water. It is better to keep the drain valve normally open in winter, and then close the drain valve to make up water before starting the next year.

3. Pipes and water pumps: pipes and water pumps discharge water at the lowest point.

4. Cooling tower: open the drain valve at the lower part of the cooling tower water pan to drain the chassis water.

5. End: There is a drain valve at the bottom of the coil, which is also opened. The drain valve is normally open in winter.

Common antifreeze mainly includes:
① Ethanol, the freezing point and boiling point of which are relatively low, is generally not used to prevent ignition.

② The price of glycerin mixed with water is very high and not economical.

③ Ethylene glycol, the freezing point of ethylene glycol is - 11.5 ° C, the boiling point is 197.4P, and the lowest freezing point can reach - 68P after mixing with water; Ethylene glycol is easy to corrode metals, so it is necessary to add anti-corrosion agent when preparing antifreeze solution. Generally, 2.5~3.5 g of disodium hydrogen phosphate and 1 g of dextrin are added to each liter of antifreeze solution; The ethylene glycol is highly hygroscopic, and the storage container should be sealed; Ethylene glycol is not easy to volatilize, so it is widely used due to its low dosage in preparation. The thermal expansion of various antifreeze fluids is relatively large, and only 95% of the total capacity of the cooling system can be added when filling; When preparing antifreeze, its freezing point should be 5 ℃ lower than the lowest temperature in the area where it is used.

Source: Xingde Mold Temperature Machine