The processes of the hvac

Edit hvac system evolution process of the most fundamental goal is to realize the temperature control to the environment, to meet the requirement of people for environmental comfort, and some manufacturability. In the early days of the hvac system, generally adopts constant flow hydraulic system, through to the end equipment volume step control to achieve the goal of the adjustment of the regional environmental temperature, such as adopt three-speed switch control fan coil air volume and air volume adjustment through the vav box, etc. This adjustment is simple, rough, and decentralized, and at the beginning of system debugging qualified after don't need to adjusted to the hydraulic system. As people demand for environmental comfort and energy-saving consciousness unceasing enhancement, this regulation has can't meet the requirements. So people started using variable flow rate hydraulic systems and variable air volume system, through the electric control valve or the valve actuator for continuous adjustment of system of water or air to achieve precise control of the environment temperature. Electric regulator either through connected to all kinds of sensors, transmitters and controllers of distributed control system, and can also be connected to the building control system of decentralized control and centralized management of the central control system, thus greatly improve the ability of the system of environmental temperature. But in some system load of the volatile variable flow system, due to the more electric regulator to work at the same time, the working state of any electric regulator change will affect other electric control valve, and the anti-interference ability of the electric control valve itself is poorer, thereby caused the instability of the whole system to the environment temperature regulation ability, adjustment precision is lower. So in the present of some large scale central air conditioning for variable flow water system, a strong anti-interference ability of the new regulator - Dynamic balance of electric valve gets more and more widely used. At the same time, a new comprehensive balance hydraulic system, also because of its high efficiency, stability and energy saving by more and more big variable flow water system are adopted