BACKPRESSURE SUSTAINING
VALVE with HYDRAULIC
CHECK FEATURE
01/05
M116-5 or M6116-5 (Globe)
Mustang Series
Operation
The Watts ACV Combination Backpressure or Sustaining Control Valve with Hydraulic Check Feature 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, and close drip-tight when
downstream pressure becomes greater than upstream pressure.
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.
If downstream pressure becomes greater than upstream pressure, downstream pressure is admitted to
the main valve cover chamber, closing the valve and preventing reversal of flow. Normal backpressure or
sustaining operation resumes when upstream pressure exceeds downstream pressure.
M1116-5 or M61116-5 (Angle)
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.
When the Model 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.
8550 Hansen Road • Houston, Texas 77075 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.wattsacv.com
BACKPRESSURE SUSTAINING
VALVE with HYDRAULIC
CHECK FEATURE
01/05
M116-5 or M6116-5 (Globe)
Mustang Series
Installation Guidelines
• Prior to installation, flush line to remove debris.
• Install valve horizontally “in line” (cover facing up), so flow arrow matches flow through the line. Avoid
installing valves 6” and larger vertically. Consult factory prior to ordering if installation is other than
described.
• Install upstream and outlet isolation valves. NOTE: When using butterfly valves, insure disc does not
contact control valve. Damage or improper valve seating may occur.
• Provide adequate clearance for valve servicing and maintenance.
• Install pressure gauges to monitor valve upstream and outlet pressure.
Other Watts ACV Pressure Relief / Backpressure or Sustaining Control Valves
M116 / M6116 Pressure Relief / Backpressure or Sustaining Valve
M116-31 / M6116-31 Pressure Sustaining Valve with Solenoid (On-Off) Feature
M116-32 / M6116-32 Pressure Sustaining Valve with Solenoid (On-Off) and Check Features
M116-52 / M6116-52 Surge Anticipator and Pressure Relief Valve
M1116-5 or M61116-5 (Angle)
8550 Hansen Road • Houston, Texas 77075 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.wattsacv.com