Watts M1116 - Manual

8550 Hansen Road • Houston, Texas 77075 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.wattsacv.com
01/05
R
Mustang Series
M116 or M6116 (Globe)
M1116 or M61116 (Angle)
Operation
The Watts ACV Pressure Relief, Sustaining or Backpressure Control Valve is designed to permitting 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. It is controlled by a normally closed control pilot
designed to: 1) Open (allowing fluid out of the main valve cover chamber) when upstream pressure is above
the adjustable setpoint, and, 2) Close (allowing fluid to fill the main valve cover chamber) when upstream
pressure is below the adjustable setpoint. An increase in upstream pressure causes the valve to modulate
toward an open position. A decrease in upstream pressure causes the valve to modulate toward a closed
position.
When the valve is installed “off the main line” on the branch of a tee, it serves as a Pressure Relief Control
Valve. The valve is normally closed, and quickly opens when upstream pressure exceeds the pilot setting,
relieving pressure, commonly discharging to a storage reservoir, pump suction, or atmosphere. When
upstream pressure is lowered below the pilot setting, the valve closes at a controlled, adjustable rate.
When the valve is located “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. The valve will close, if
necessary, until upstream pressure is above the pilot setting. The valve should be specified to include the
optional opening speed control and position indicator when used for Pressure Sustaining applications.
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. The valve should be specified to include the optional opening
speed control when used for Backpressure applications.
PRESSURE RELIEF, SUSTAINING,
or BACKPRESSURE
CONTROL VALVE