A two-way valve has one inlet and one outlet port, controlling flow through a single circuit path by modulating between fully open and fully closed positions. These valves are used for load control applications where flow variation regulates energy transfer. They cannot divert or mix flows between multiple circuits.
Technical Details
Two-way valves are available in equal percentage and linear characteristics with sizes from DN10 to DN100. They can be manual ball valves for isolation or automatic modulating valves for temperature control. Common configurations include straight-through designs and angled bodies for space-constrained installations.
Applications in HVAC
Two-way valves control chiller flow, boiler supply, fan coil units, and convector circuits. They are installed in zone control loops and thermostat-driven applications where on-off or proportional flow control is required. Typical pressure ratings range from 250 psi to 600 psi.
Practical Significance
Two-way valves are the most common control valve type in residential and light commercial HVAC systems. They require accurate sizing based on circuit Cv and expected pressure drops. Proper installation includes strainer protection and adequate isolation for maintenance access.