Two-port control valve
Selection of Control Valves in Variable Flow Systems (BG 51/2014) written by Chris Parsloe and published by BSRIA in June 2014, defines a two-port control valve (2PV) as: ‘An actuated control valve with two ports (input and output) the opening of which, in normal operation, varies between fully open and fully closed thereby varying the flow to a terminal device.’
It suggests that typical applications include; modulating control of heating or cooling output from air handling units, fan coil units, chilled beams and plate heat exchangers in variable flow branches.
--BSRIA
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