Standard Components
Operation
The Pressure Sustaining and Solenoid (On-Off) ACV is designed to
permit flow when upstream pressure is above the adjustable set-
point 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 adjust-
able setpoint. An increase in upstream pressure causes the valve to
modulate toward an open position. A decrease in upstream pres-
sure causes the valve to modulate toward a closed position.
The Solenoid Pilot will either open to allow regulating action, or
close the valve drip-tight when energized. Specify energize to open
or close the Main Valve and voltage PRIOR to ordering.
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.
1
X
X
X
Y/FC
3
(AOS)
1
2
P/L
4
CLOSES VALVE
OPENS VALVE
FLOW
1. Clear the line free of slag and other debris.
2. Install the valve so that the FLOW ARROW marked on the valve body/tag corresponds to flow through the line.
3. Close upstream and downstream isolation valves.
4. Open the isolation ball valves in the control tubing if so equipped. Failure to open these will prevent the valve from functioning
properly.
5. Connect solenoid wiring leads to the desired switching device, using safe, standard electrical procedures.
6. Install pressure gauge at a location upstream of the valve.
Start-up of an automatic control valve requires that proper procedures be followed. Time must be allowed for the valve to react to
adjustments and the system to stabilize. The objective is to bring the valve into service in a controlled manner to protect the system
from damaging over-pressure.
1 – Main Valve (905GD - Single Chamber)
2 – Pressure Sustaining Control
3 – Adjustable Closing Speed
4 – 2-Way Solenoid
X – Isolation Cocks
Installation
920GD-15 (Globe) Pressure Sustaining Control Valve with
Solenoid (On-Off) Feature
2 IOM-A-ACV-920-15_620-15 2115
EDP# 1917048
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