Watts S1127-8 - Manual

8550 Hansen Road • Houston, Texas 77075 • (Ph) 713.943.0688 • (Fx) 713.944.9445 • www.wattsacv.com
01/05
R
Stainless Series
ONE-WAY FLOW ALTITUDE VALVE
with PRESSURE SUSTAINING
FEATURE
S127-8 or S6127-8 (Globe)
S1127-8 or S61127-8 (Angle)
Operation
The Watts ACV One Way Flow Altitude Valve with Pressure Sustaining Feature is designed to open, allowing
flow into a reservoir or elevated storage tank (tank fill), and close drip tight when high water level is achieved.
The valve will also throttle to sustain a minimum upstream pressure during tank filling operations. The
Altitude Pilot remotely senses static tank head pressure (water level) through a field installed sensing line,
and directs pressure into and out of the cover chamber of the 3-way Accelerator Pilot. When the cover of the
Accelerator Pilot is pressurized, the main valve cover chamber is vented downstream, causing the valve to
open. When the cover of the Accelerator Pilot is de-pressurized, the main valve cover chamber is connected
to upstream pressure, causing the valve to close drip tight.
As water level decreases, static tank head pressure falls below the adjustable setpoint of the Altitude Pilot,
causing it to pressurize the cover of the Accelerator Pilot, opening the valve. As water level increases, static
tank head exceeds the adjustable setpoint of the Altitude Pilot, causing it to depressurize the cover of the
Accelerator Pilot, closing the valve drip tight. Valve opening and closing speeds are separately adjustable.
The Position Indicator with Air Bleed Petcock allow for visual indication of valve position, and allows easy
venting of air entrapped in the main valve cover chamber.
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 through the integral orifice of the Accelerator
Pilot, allowing the valve to modulate toward a closed position, raising upstream pressure. Normal tank fill
operation resumes when upstream pressure is above the sustaining pilot setpoint.
Specify Tank height PRIOR to ordering.