The water circulation is the way in which the swimming pool inlet water and the swimming pool return water continuously flow in the pool. In layman's terms, it is to solve the problem of where to take water from the swimming pool (that is, return water) and to send the purified water into the swimming pool from which part of the swimming pool, so as to effectively remove the floating on the surface and sediment pollution at the bottom of the pool. 

At present, water circulation be commonly divided into three types: downstream, countercurrent, and mixed flow.

Downstream

Downflow means that water enter the pool from the inlet on the wall, and return from the outlet on the deep end of the pool. The advantage of downstream is that the sediment at the bottom of the swimming pool can enter the filter smoothly, avoiding the accumulation of excessive sediment in the swimming pool, but the floating debris on the surface of the pool water requires manual treatment.

advantage:

1. Lower requirements for civil construction, and lower the civil construction cost.

2. Simple pipeline layout, convenient for management and maintenance.

3. The elevation requirement is 1m lower than the water surface of the swimming pool.

4. The overflow water in the overflow ditch is not reused to avoid water pollution caused by the existence of debris in the overflow ditch.

shortcoming:

1. The pool water at the lower part of the water inlet cannot circulate effectively. The water distribution is not as uniform as the counter flow, which is prone to dead water areas, resulting in uneven water quality in the pool.

2. All overflow water from the overflow tank is drained out, which wastes a lot of water.

3. The negative pressure of water absorption at the bottom of the pool is relatively large, which is relatively dangerous, and it is easy to cause personal injury caused by the adsorption of human body or hair by the return port.

4. The water surface cannot eliminate the water waves generated during swimming, and the swimming resistance is large.

Counterflow

Counter-flow is the water entering the pool from the bottom inlet port of the pool and overflowing around the swimming pool. This method can quickly overflow the suspended matter on the surface of the pool, and then enter the swimming pool through the bottom of the swimming pool after being treated by the circulating water treatment equipment. This method requires the pool to be at the same height around the pool, which requires relatively high construction.

Advantage:

1. It can prevent the occurrence of eddy currents, short currents and dead water areas;

2. There are many distribution outlets, and the dirty impurities on the inner surface of the pool can be collected by the overflow tank and then enter the water treatment system, which can effectively purify the surface water and suspended substances of the pool water. The overall water quality is good and the water quality is clear.

3. Ensure stable water quality in different water layers and different parts of the pool.

Shortcoming:

1 The requirements for civil construction are higher, and the civil construction cost is higher than that of downstream flow.

2. It is necessary to configure a balanced water tank. The room occupies a large area. Generally, the height of the computer room is required to be about 3m lower than the water surface of the swimming pool to ensure the overflow and return water.

3. The construction of water distribution at the bottom of the pool is difficult, the pipelines are more than downstream and the overflow pipe diameter is larger, and the construction, installation and maintenance are more difficult.

4. There is a lot of noise in the overflow tank.

Mixed flow

Mixed flow is a combination of countercurrent and downstream flow. Countercurrent and downstream flow exist at the same time, water enters the pool from inlets on the wall and the bottom. It has certain advantages to solve the problem of suspended matter on the surface of the pool water and the problem of sediment at the bottom of the pool, but the engineering difficulty is greater than that of flow and downstream flow, and the cost is relatively high.

Advantage:

It not only has the advantages of the counter-flow pool water circulation model, but also has the advantage that the back-water at the bottom of the downstream pool can be washed away by the water flow and take away part of the deposited dirt at the bottom of the pool. Although there are few examples of this method in my country, it is known that the effect is satisfactory.

Shortcoming:

1. The construction cost is high, the basic requirements for the construction are the same as those of the countercurrent, it occupies a large area and the investment is high.

2. The actual flow distribution of pool bottom and overflow return water is difficult to control reasonably.

3. There is a lot of noise in the overflow tank.

4. The pipeline construction is similar to the counter-flow type. It is more complicated than the counter-flow type, and the overflow pipe diameter is required to be larger. The construction is more complicated.

5. The return pipe at the bottom of the pool is connected with the suction pipe of the balanced water tank, and the backflow is prevented by the check valve. According to actual experience, if there is a slight problem with the check valve, there is a high probability of water leakage into the water tank, resulting in a large amount of water waste and even flooding the engine room.

Besides the pool heat pump for the swimming pool, the circulation system is directly related to the safety and health of swimmers. The swimming pool water treatment system engineer should reasonably choose and implement the optimal circulation method according to factors such as the size of the swimming pool and the flow of people. Therefore, when customers choose a company, they must choose a company with rich experience and guaranteed product quality like INVERPAC company, INVERPAC company provides high quality and stable performance pool heat pumps, if you are interested,  feel free to contact us.