Differential Pressure Control Valve Optimizes HVAC Performance

Working principle of differential pressure control valve

The differential pressure control valve does not require any external energy and relies on the pressure change of the medium to be regulated to automatically adjust. Its basic working principle is to sense the inlet and outlet pressure difference through the pressure-sensitive membrane, and adjust the valve opening according to the preset pressure difference value to achieve the purpose of constant pressure difference. Inside the valve, the spring, pressure-sensitive membrane and valve stem are interconnected to form a balance system. When the inlet and outlet pressure difference exceeds or falls below the set value, the pressure-sensitive membrane will drive the valve stem to move, thereby changing the valve opening to ensure that the pressure difference remains within the set range.

Application scenario

Household metering system

In the household metering heating system, the differential pressure control valve can effectively control the pressure difference of each user and keep it constant. Due to the different heat requirements of each user, it is difficult for the traditional system to meet personalized needs, while the differential pressure control valve can automatically adjust according to the actual heat usage of the user, improving the flexibility and adaptability of the system. In addition, it can also help stabilize the operation of the system and reduce energy waste caused by flow fluctuations.

Automatic control system

In HVAC systems with a high degree of automation, differential pressure control valves also play an important role. It can be used in conjunction with automation equipment such as sensors and controllers to achieve remote monitoring and intelligent adjustment. By real-time monitoring of pressure changes in the pipeline network, the differential pressure control valve can respond quickly and adjust the valve opening to ensure that the system is always in the best operating state. This automatic adjustment capability not only improves the stability of the system, but also reduces operation and maintenance costs.

Cold and heat source protection

In cold and heat source units, such as fuel and gas units and chillers, the system flow changes greatly due to user flow adjustment, which may bring safety hazards to the unit. By installing a differential pressure control valve on the bypass pipeline, the valve can be automatically opened when the system flow decreases, increasing the flow through the cold and heat source to ensure the safe operation of the unit. Compared with traditional electric control valves, self-operated differential pressure control valves have higher reliability and economy.

Central heating project

In central heating projects, the pressure conditions between high buildings and low buildings are quite different, and the system often needs to be pressure-regulated. With the help of differential pressure control valves, they can be set at appropriate positions in the water supply and return pipes to keep the dynamic water pressure line at the rear of the pipe network relatively low to meet the pressure requirements of low-rise building radiators; at the same time, the dynamic water pressure line at the front of the network is relatively high to prevent high buildings from emptying. This flexible pressure regulation capability is of great significance to improving the overall performance and operational stability of the system.

Performance characteristics

1. Constant controlled system pressure difference: The differential pressure control valve can automatically adjust the valve opening to ensure that the pressure difference of the controlled system remains within the set range.
2. Support internal autonomous regulation of the controlled system: By sensing the pressure changes in the pipe network, the differential pressure control valve can autonomously adjust the system flow to meet the personalized needs of users.
3. Absorb external network pressure difference fluctuations: During system operation, pressure fluctuations in the pipe network are inevitable. The differential pressure control valve can absorb these fluctuations and keep the system stable.
4. Adopt advanced stepless pressure regulation structure: The adjustable ratio of the control pressure difference can reach 25:1, which can meet the pressure regulation needs of different occasions.
5. With automatic blockage elimination function: Through regular cleaning and maintenance, the differential pressure control valve can automatically eliminate blockages and keep the system unobstructed.

Installation and use

The installation of the differential pressure control valve should follow certain specifications and requirements. First, ensure that the flow direction of the medium is consistent with the direction of the arrow on the valve body; second, the valve should be installed on the return pipe and connected to the pressure pipe; in addition, a filter should be installed in front of the pressure pipe to avoid water quality problems affecting the valve performance. During use, the valve should be checked and maintained regularly to ensure its normal operation. If the system flow is found to be abnormal, the pressure difference can be adjusted by adjusting the pressure regulating valve stem.

The differential pressure control valve is widely used and important in HVAC systems. It can not only improve the stability and operating efficiency of the system, but also meet the personalized needs of different users. With the continuous development and progress of science and technology, the performance and function of the differential pressure control valve will continue to improve and improve, providing more powerful support for the intelligent and efficient operation of the HVAC system.