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S116, S1116

Pressure Relief, Sustaining or Backpressure

Lead Free* Models Available


The WATTS ACV Pressure Relief, Sustaining or Backpressure Control Valve is designed to permit flow when upstream pressure is above the adjustable setpoint of the control pilot, and throttle toward closed when upstream pressure falls below the adjustable setpoint.

When the valve is installed "off the main line" on the branch of a tee, it serves as a Pressure Relief Control Valve. It is normally closed, and quickly opens when upstream pressure exceeds the pilot setting, relieving excess pressure.

When valve installed "in line" connecting two distribution zones, the valve acts as a Pressure Sustaining Control Valve. When pressure in the upstream zone falls below the pilot setting, the valve modulates toward a closed position, sustaining pressure in the upstream zone.

When the valve is installed "in line" on the discharge of a pump, it acts as Backpressure Control Valve. When pump discharge pressure falls below the pilot setting, the valve modulates toward a closed position, increasing backpressure against the pump.

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Disclaimer: Watts product dimensions in U.S. customary units and metric are approximate and are provided for reference only. For precise measurements, please contact Watts Technical Service. Watts reserves the right to change or modify product design, construction, specifications, or materials without prior notice and without incurring any obligation to make such changes and modifications on Watts products previously or subsequently sold.

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*The wetted surface of this product contacted by consumable water contains less than 0.25% of lead by weight.

Additional Information

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