Honeywell VP531C1018 3/4" Pneumatic Terminal Unit Valve

The Honeywell VP531C1018 is a 3/4" pneumatic terminal unit valve with a normally-open, single-seated straight-through design in brass construction with a copper seal. It has NPT connections at both 3/4" inlet and outlet, a 2.6 CV flow rating, and operates on a 2-5 psi actuator spring range, with an optional orange 3-10 psi spring available for different close-off requirements. The valve is temperature rated to 240°F and measures 4-3/16" x 2-7/16" x 3-1/2", suited for commercial VAV boxes and terminal unit HVAC control applications. Professional installation is required. Watch for failure symptoms such as a terminal unit not responding to control signal, valve stuck open, improper flow control, or inconsistent zone temperature, which typically indicate valve or actuator issues requiring replacement.