Pressure Independent Control Valves (PICV) can help reduce energy costs and increase occupant comfort in heating and cooling coil applications in buildings. A PICV is best described as two valves in one: a standard 2-way control valve and a balancing valve.
Pressure independent control valves are an automatic temperature control valve and an automatic flow regulating valve packaged in one valve body. A ball valve with a characterized insert performs as a regular actuated temperature control valve, and a pressure control cartridge provides automatic flow regulation to maintain a constant flow of hot or chilled water regardless of system pressure changes.
They are used in many closed loop HVAC applications. Systems with pressure independent control valves do not need to be balanced and rebalanced during commissioning. They regulate and maintain a constant flow to the coil as water pressure in the system varies with the changing loads.
This delivers better comfort, increases energy efficiency, reduces actuator operation and reduces expensive call backs. Pressure independent valves allow the system to perform better. With the right flow to each coil, boilers and chillers are most efficient
PICV obtain optimal results because only the necessary amount of hot water (in GPM) and chilled water (in GPM) is delivered to the heating and cooling coils. Standard 2-way control valves allow for overflow and underflow especially if the CV is oversized or undersized. This generates excess water to the pump to compensate for their inaccuracy, which increases pumping cost.
The actuators on PICV valves do not cycle as often as standard 2-way valves to compensate for pressure changes in the system that impact the flow, which results in energy savings.
