Precautions for water treatment of central air conditioning chillers

Precautions for water treatment of central air conditioning chillers

The central air conditioner of many units will have various problems during operation. After analysis, a considerable part of it is caused by the unreasonable design of the design department or even the design error. Common unreasonable design problems are as follows:

Precautions for water treatment of central air conditioning chillers

　　 1. In order to prevent scale, a magnetic water device is designed in the water treatment system

There are many types and names of water magnets, some are called electronic water descalers, high-frequency water changers, etc. In short, they magnetize water molecules, and polarized water molecules have strong electronegativity, attracting Calcium and magnesium ions can delay the scaling time and achieve the purpose of anti-scaling. Water molecules with strong electronegativity can also degrade scale and rust. Therefore, some manufacturers say that the products have the functions of anti-scaling, anti-corrosion, descaling and rust removal. Indeed, magnetic water heaters have certain positive effects mentioned above. However, if the installation quantity and installation location of the magnetic water device are not designed reasonably, it will cause serious corrosion to the water system, and its negative effect is far greater than the positive effect. Cause serious harm to air conditioning equipment and water systems.

　　2, it is best not to use softened water as the replenishment of the central air conditioner

　　 It was discovered in 1987 that sodium ion exchange regeneration waste liquid caused permanent pollution to groundwater. In Beijing, 2 to 5 kilograms of salt are discharged underground for every ton of softened water produced. Due to the provisions of the low-pressure boiler water quality standard GB1576, almost all industrial boilers use softened water as boiler feed water. There are more than 9,000 boiler houses in Beijing, among which there are more than 2,800 large-scale boiler houses, and hundreds of thousands of them are discharged underground every year. Tons of salt have caused permanent pollution of groundwater, leading to increased risk of humans suffering from high blood pressure, heart disease, and cancer. The consequences are terrible. The United States has restricted the use of sodium ion exchangers.

　　3. A vertical decontamination device should be installed in the cooling water system

At present, the decontamination devices installed in the central air conditioners of chillers all over the country are all inverted Y-shaped, installed on the riser in front of the air conditioning unit entrance. This inverted Y-shaped decontamination device on the riser can only Capture construction waste in the early stage of equipment operation to prevent these waste from entering the condenser. However, this inverted Y-shaped decontamination device cannot capture fine scale and rust in daily operation, so it will cause condenser fouling, sludge and other impurities.

　　 The correct way is to install a vertical decontamination device before the water inlet of the condenser to trap various impurities in the cooling water system in the decontamination device.

　　4. Design a fast drain valve on the outlet side of the cooling water and chilled water of the air conditioner

At present, many units do not have quick drain valves installed at the cooling water end plates or chilled water end plates of the central air conditioner, and some units also use seals to block these drain outlets. In fact, this approach is very wrong, and it is easy to cause internal accumulation in the air conditioner. The accumulated impurities affect the heat exchange efficiency and also cause the condenser to be cleaned regularly every year. Hangzhou Air Conditioning Repair Service Center specializes in cleaning air conditioners.

　　 The correct method is to discharge sewage from the condenser water outlet side of the cooling water system 2 to 3 times a week according to the "three-open and three-close method". For the chilled water system, discharge sewage according to this method once a week.

　　5. Install a tap water meter on the water supply pipe of the cooling tower and the water supply pipe of the chilled water supply tank.

　　 At present, there is no tap water meter installed on the cooling water and chilled water supply pipes of a considerable part of the central air conditioners, so that users do not know how much water is in the system or how many tons of water are added per day, which brings a lot of trouble to operation and governance. Because central air-conditioning water treatment generally adopts chemical treatment, it must be dosed according to the amount of water supplemented and the amount of system water, so these two water meters are indispensable in design.