Considerations for Selecting Modulating Control Valves

Selecting and sizing HVAC control valves can sometimes be a daunting task for many designers. In the past, control valves were primarily pressure dependent, meaning the flow is dependent on the differential pressure across the valve for any given valve position. Pressure independent control valves have gained market share in recent years. Today, we have many available devices to control fluid flow when deciding how to best control water heating and cooling loads.