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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 

© 2021 Watts

Summary of Contents for Ames 920GD-15

Page 1: ...Setting the Pressure Controls 3 Maintenance Schedule 6 Trouble Shooting Guide 6 Valve Disassembly Instructions 8 ACV Schematic 11 Local building or plumbing codes may require modifica tions to the inf...

Page 2: ...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 indicato...

Page 3: ...ed air by loosening a fitting on the valve or a plug at the highest point of the valve as sembly STEP 5 Pressure the line by opening the upstream isolation valve slowly Air is vented through the air b...

Page 4: ...valve until the inlet pressure drops to the desired setting Fine tune the Reducing Control adjustment to the pressure reduc ing setpoint as detailed in Step 7 STEP 10 Adjust the Sustaining Control sc...

Page 5: ...counterclockwise increasing the rate of closing IF INSTALLED Opening Speed Flow Control Adjustment The Opening speed flow control allows free flow into the cover and re stricted flow out of the cover...

Page 6: ...specification sheets for approximate cover capacity A continuous flow of water from the open port indicates a damaged diaphragm or loose disc diaphragm assembly Disassemble valve and replace diaphragm...

Page 7: ...djust opening speed control to verify functionality adjust as required Standard setting for open ing speed control is 1 1 2 2 1 2 turns open from full closed position Can be adjusted in field Main Val...

Page 8: ...move cover nuts and washers 3 Remove the cover If cover is not free to be removed loosen it by tapping upward along its outside edge with a dull cold chisel pic tured above a Large valves may require...

Page 9: ...rush or by using a Mineral Dissolving Solution Inspect parts for wear and replace if necessary 7 Inspect valve seat If seat is not damaged removal is not necessary Valve seats 6 and smaller are thread...

Page 10: ...ts in a crossing pattern to ensure even distribution Test the Disc and Diaphragm Assembly for smooth travel by following the Freedom of Movement Test procedure in previous section 11 Test the integrit...

Page 11: ...el 9 Stem Washer ASTM A276 304 Stainless Steel 10 Diaphragm Washer ASTM A536 65 45 12 Epoxy Coated Ductile Iron 11 Diaphragm Buna N Nitrile 12 Disc Retainer ASTM A536 65 45 12 Epoxy Coated Ductile Iro...

Page 12: ...resulting from labor charges delays vandalism negligence fouling caused by foreign material damage from adverse water conditions chemical or any other circumstances over which the Company has no cont...

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