This BSRIA Test Standard supersedes BTS 1/2012 Test Method for Pressure Independent Control Valves. It incorporates refinements to the test method for pressure independent control valves (PICVs) and a new test method that deals specifically with differential pressure control valves (DPCVs).
PICVs can be applied to variable flow systems (such as those containing air handling units, fan coil units and chilled ceilings) and constant flow systems (such as one-pipe central heating systems). The control valve can be used to ensure a controlled flow passes through the system regardless of the pressure experienced. Pressures may vary as a result of varying flow rates in other parts of the system responding to varying loads.
DPCVs are important to the efficient operation of systems based on variable speed pumps and two-port control valves. In variable flow circuits, DPCVs are typically used to maintain a constant pressure differential across a sub-branch. This protects downstream control valves from excessive pressures and neutralises the effects of pressure variation caused by other control valves in the circuit.
This BSRIA Test Standard was written by BSRIA in collaboration with the building services industry and valve manufacturers.