Auto bypass valve

Auto bypass valve is a direct-acting control valve designed to automatically maintain a specified pressure differential between the inlet and outlet ports. When the pressure differential exceeds the set value, the valve disc automatically opens, and correspondingly closes when the pressure drops.

Applications

Auto bypass valves are used to optimize hydraulic regimes in systems with dynamically changing flow rates:

• Protection of pumps from running with zero flow in the heat exchange station.
• Maintaining a constant flow rate in the heat source circuit in the boiler room.
• Maintaining a constant pressure differential between the supply and return branches of the heating system, necessary to optimize the operation of radiator thermostatic valves.

Advantages

• Low cost
• Simple design
• High reliability
• Small size and weight
• Does not require external power
• Can be installed in any working position
• No maintenance required
• Pressure is adjusted by rotating a single adjusting screw

Disadvantages

• The accuracy of pressure maintenance is influenced by the temperature of the working medium.
• Low accuracy of pressure maintenance adjustment, and the more open the valve, the more the actual pressure difference exceeds the setting.

Alternatives

1. A regulator that opens when the set pressure is exceeded, pressure differential regulator, can be used as an analogue of the pressure relief valve with greater pressure maintenance accuracy.

2. If the pressure in the return pipeline is stable, which is typical for heating systems with dependent connection to the heating network, the same effect can be achieved by installing a pressure regulator 'upstream'.