Watts M1115-43 - Manual

8550 Hansen Road • Houston, Texas 77075 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.wattsacv.com
01/05
R
Mustang Series
M115-43 or M6115-43 (Globe)
M1115-43 or M61115-43 (Angle)
Operation
The Watts ACV Combination Pressure Reducing and Sustaining Control Valve with Downstream Surge
Control Feature is designed to automatically reduce a fluctuating higher upstream pressure to a constant
lower downstream pressure regardless of varying flow rates, throttles to sustain a minimum upstream
pressure, and will quickly modulate toward a closed position if downstream pressure suddenly becomes
greater than the desired regulated setpoint. The quick closing action prevents possible damaging high inlet
pressure from passing through the valve to downstream piping. Pressure Reducing action is controlled by
a normally open, pressure reducing pilot designed to: 1) Open (allowing fluid out of the main valve cover
chamber) when downstream pressure is below the adjustable setpoint, and 2) Close (allowing fluid to fill
the main valve cover chamber) when downstream pressure is above the adjustable setpoint. A decrease in
downstream pressure causes the valve to modulate toward an open position, raising downstream pressure.
An increase in downstream pressure causes the valve to modulate toward a closed position, lowering
downstream pressure.
The normally closed sustaining pilot remains open when upstream pressure is above the adjustable setpoint,
and modulates toward a closed position if upstream pressure falls below the setpoint. As the sustaining pilot
closes, fluid is directed into the main valve cover chamber, allowing the valve to modulate toward a closed
position, raising upstream pressure. Normal pressure reducing operation resumes when upstream pressure
is above the sustaining pilot setpoint, and downstream pressure is below the reducing pilot setpoint.
If downstream pressure suddenly becomes greater than the desired regulated setpoint, the normally closed
surge control pilot opens and rapidly admits higher inlet pressure into the valve cover, increasing rate of
valve closure. Normal pressure reducing operation resumes when downstream pressure decreases below
the desired regulated setpoint.
PRESSURE REDUCING and
SUSTAINING VALVE with
SURGE CONTROL FEATURE