Water quality management of central air conditioned water systems

With the development of society, there are more and more places in China that use the best air conditioning water system for indoor temperature regulation. **Water quality problems in the use of air conditioners are also becoming more and more prominent.

Among them, the fouling of the circulating cooling water system and refrigerator, the growth of algae and fungi, the appearance of black water and rust slag in the chilled water system, and the blockage of the fan coil unit due to rust slag are particularly prominent.

These phenomena make it difficult for the operating staff to cope with and affect the normal operation of the chiller. Therefore, in order to ensure the normal effect of the entire air conditioner, prolong the service life of the air conditioning equipment, and save the operating costs of the equipment, it is necessary to carry out water quality management on the air conditioner, which should be a perennial maintenance project synchronized with the construction of the air conditioner.

So, how to manage the water quality of air conditioners?

First, the construction plan

1. Chilled water system approach work plan (the first stage of system cleaning)., the first day. Clean the expansion tank by manual method, then add SD-87 bactericidal algaecide to the water tank, open the pump for 16-24 hours, and do the whole system of sterilization, algae removal and stripping of domestic sludge treatment.

The next day. After discharging chilled water at the lowest gate valve of the chilled water system, add water to full, then add SD-81 cleaning agent to the expansion water tank, and turn on the pump for 24 hours to penetrate and peel off the floating rust and oil in the system.

Day 3 - Day 5. Discharge the chilled water and discharge the cleaned rust residue and sludge out of the refrigeration system. Disassemble the Y-type filter of the refrigeration system, remove the debris of the filter screen, seal the filter again, and fill the system with water and exhaust until the chilled water is full. Turn on the refrigeration pump for half to 1 hour, stop the pump to drain the whole system, drain it and then inject it, and then rinse it repeatedly until the water is clear and transparent.

Day 6 - Day 7. Add SD-82 pre-film solution to the expansion tank, open the pump and cycle for 48 hours, the agent can be coated with a layer of film on the metal surface to prevent dissolved oxygen adsorption in the water on the pipe wall to play an anti-rust role.

Day 8. Open the pump cycle to the eighth day, discharge 2 3 chilled water in the expansion tank with SD-84A corrosion inhibitor, open the pump cycle for 2 hours, so that the drug is evenly distributed in the system. Test the pH value, and the pH value is normal at 8-10. The agent can maintain the anti-rust effect for one year without leakage in the system.

2. Cooling water system approach work plan (the first stage of system cleaning)., the first day. Use a high-pressure water gun to clean the cooling tray, filler, etc., and wash them of dust, sludge and moss.

The next day. SD-86 bactericidal algaecide was added to the tower, and the pump was turned on for 16-24 hours for the whole system of sterilization and algae sterilization.

Day 3. Add SD-81 cleaning agent to the tower, open the pump for 16-24 hours, the agent can penetrate and peel off the floating oil stain of the cooling system.

Day 4-5. Drain the cooling water, clean the cooling tower, disassemble the Y-filter of the cooling water system, and clean the debris in the filter.

Day 6 - Day 7. SD-82 pre-film solution is added to the cooling tower and the pump is circulated for 48 hours, and the agent can be coated with a layer of film on the metal surface to prevent dissolved oxygen in the water from adsorbing on the pipe wall to prevent rust.

Day 8. Open the pump cycle to the eighth day, drain 2 3 cooling water, and clean the cooling tower. After filling with water, SD-89 scale and corrosion inhibitor was added to the cooling tower. This agent strengthens the effect of the protective film.

3. **Chemical cleaning scheme of air conditioning host:Close the inlet and outlet valves, open the sewage valve, and check the closure of the inlet and outlet valves.

Open the end cover of the condenser, take a little scale on the surface of the copper tube, and experiment with various descalers.

According to the low-in, high-output method, properly connect the cleaning pump.

Use an external water pump to fill the bucket with water and start the cleaning pump to circulate until it is level.

A corrosion inhibitor is added to the barrel and the cleaning pump cycle is started for a period of time.

Slowly add descaler to the bucket in stages, and rinse repeatedly with tap water until the pH value reaches about 7.

Neutralizer is added to the barrel for half an hour cycle.

Discharge the neutralizer and rinse it repeatedly with tap water until the pH value reaches about 7.

Add the pre-film agent to the barrel, open the pump and circulate for 60 minutes, and then discharge the pre-film.

Rinse the cleaning pump with tap water.

Open the end cover and manually pass the cannon.

Second, the daily management of the start-up stage

1. Daily management of refrigeration systemSince the system is contained, as long as the system is leak-free, there is very little loss of water and medication. In addition, the anti-rust validity period of the corrosion inhibitor is one year, and the monitoring system for leakage can be supplemented in time with the refrigeration corrosion inhibitor SD-84. The bactericidal algaecide SD-87 is dosed once every two months.

2. Daily management of cooling water system:Dosing work: SD-86 bactericidal algaecide is added once a week. (If it is a unit in the area below the office, it will be redosed once a month);SD-89 scale and corrosion inhibitor is added once every half month. (If it is a unit in the area below the office, it will be redosed once a month);

Sewage work: Because the cooling system is open, the evaporation and dispersion of water lead to an increase in the concentration multiple of the cooling water, and the harmful ions in the water increase exponentially. Harmful acids, domestic sludge, and pollutants in the atmosphere will enter the cooling tower, so the cooling tower should be cleaned once a month and discharged once every half month. (If it is a unit in the area below the office, the sewage is discharged once a month).

Third, the shutdown phase work

The main condenser, absorber, and evaporator are fired.

Take a sample of cooling water, and then clean the cooling tower, and the time of washing the tower must be made with Party A.

Do anti-rust paint for the expansion tank once a year.

If the system needs to be renovated or overhauled, and the freezing and cooling water needs to be discharged, we should be notified in time, and we will immediately arrange staff to add corrosion inhibitors and other agents.

The cooling water should be drained and empty pipes (according to the ambient temperature) during the shutdown phase, and the system will corrode quickly when there is no water in the system.

In our approach and daily work, Party A should arrange 1-2 air-conditioning personnel to coordinate the work and be responsible for opening the circulating water pump.

The copper pipes in the condenser and evaporator are free of scale and rust, and maintain good heat exchange efficiency.

After the refrigeration system enters the site, the hanging piece test will not be rusted within one year.

The water quality in the air-conditioning system should be kept turbid, i.e., clear, without serious leaks (or if there are leaks but even if the tonic reaches the required concentration) and without empty pipes (no water in the system).

After water treatment, the water quality reaches the following standards.