In air conditioning and heating systems, the hydraulic balance of the water circulation system as the energy distribution is very important. A balanced hydraulic system is the basis for meeting user needs and saving operating energy. In air conditioning and heating systems, cold (hot) media is delivered to each user by a closed piping system. For a well-designed pipe network system, each user should be able to obtain the designed water volume when the opening control valve (electric control valve, temperature control valve, etc.) has an opening of 100%, and each user changes the opening of the end control valve. Both the required flow rate and the mutual interference are obtained. Such a water system is a hydraulically balanced system, otherwise it is a hydraulic imbalance system, and the hydraulic imbalance is also called a hydraulic imbalance.

Hydraulic imbalances are generally divided into static imbalance and dynamic imbalance. The so-called static imbalance is also called steady-state offset. That is, in the system, the actual traffic does not match the design traffic under the design state of each user. This hydraulic imbalance is fundamental, and if it is not addressed, the impact is always there. For constant flow systems, this imbalance can be solved with a static balancing valve or a dynamic balancing valve. The difference is that the former requires instrumentation for adjustment, while the latter does not. The so-called dynamic imbalance is also called stability imbalance. That is, when the water flow of some users changes (closes or adjusts), the resistance distribution of the system changes, which causes the flow of other users to change. This hydraulic imbalance is randomly changing and dynamic. This imbalance phenomenon static balance valve can not be solved, can only be solved with a dynamic balance valve. For example, if a building is a six-story building, if the dynamic flow balancing valve is not installed, the water system will dynamically deviate during actual operation. In the air-conditioning cooling season, the first to second floor rooms will be too cold, the three to four-story rooms will just reach the design comfort temperature, and the five to six-story rooms will be too hot. On the contrary, in the heating season, the first to second floor rooms will be too hot, the three to four floors will just reach the design comfort temperature, and the five to six floor rooms will be too cold. After installing the dynamic flow balance valve, whether it is used in all of the first to sixth floors or only some rooms are using air conditioning, all rooms can reach the design temperature.