Standard Components
Operation
The Two-Way Flow Altitude Automatic Control Valve (ACV) with
Delayed Open for Return Flow Feature is designed to control the
maximum water level in elevated water storage tanks and to allow
flow from the tank back into the water system after the system
water pressure has fallen below the elevated storage tank shut-off
head pressure by an adjustable amount of pressure. The high level
P(L)
1
X
X
X
X
Y/FC
7
4
8
2
CLOSES VALVE
OPENS VALVE
FLOW
3
(Tank Sense Line)
5
6
control is accomplished using a spring loaded 3-way altitude control and a large ported 3-way accelerator control. The altitude pilot
responds to the rising water level in the storage tank through a field installed sense line. The altitude pilot will signal the accelerator to
open the main valve by venting the main cover chamber or close the main valve by pressurizing the main cover chamber. When the
system pressure falls below the tank head pressure the Delayed Open for Return Flow feature is achieved by a normally open pressure
control that holds the return flow line closed until the system pressure falls to the set point of the normally open pressure control.
Specify Tank height PRIOR to ordering.
1 – Main Valve (905GD - Single Chamber)
2 – Model 22-1 Accelerator Control
3 – Altitude Control
4 – Delayed Opening Control
5 – Adjustable Opening Speed
6 – Adjustable Closing Speed
7 – 3-Way Ball Valve
8 – Check Valve
P – Position Indicator
X – Isolation Cocks
1. Prior to installation, flush line to remove debris.
2. Install valve so the flow arrow matches flow through the line, and gauges to monitor valve inlet and outlet pressures. A Position
Indicator can be installed to provide visual indication of valve position and operation without disassembly.
3. Install isolation valves upstream and downstream of the main valve.
Note:
If using butterfly valves, ensure valve disc does not contact the main valve.
4. Provide adequate clearance for valve servicing and maintenance. Refer to valve servicing dimensions on next page. Avoid installing
valves 6" and larger in the vertical position (main valve stem horizontal). Automatic Control Valves (ACVs) are designed for horizon-
tal in-line installation, with the cover facing up (main valve stem vertical). Slow operation or premature stem and guide wear may
occur if valve is not installed according to factory recommendations. Consult factory for detailed engineering review prior to order-
ing if valve is to be installed other than horizontally in-line.
5. If valve is equipped with a pilot control system, extra precautions should be made during installation to protect the piping circuit
from damage. Only remove the pilot control system from the valve if necessary. Tubing and fittings should be kept clean and
replaced exactly as removed. Consult appropriate hydraulic schematic to ensure proper re-assembly.
6. Check to confirm that the sense line is installed and connected.
7. Installation of a pressure gauge on the sense line of the tank full-delayed opening system will assist in adjustment of setpoint. The
amount of pressure drop can be read at the time the main valve starts opening.
8. After installation, vent entrapped air from valve cover and pilot system by following instructions on Technical Bulletin.
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.
Installation
960GD-13-17 (Globe) Two-Way Flow Altitude Control Valve with
Delay Open for Return Flow
2 IOM-A-ACV-960-13-17_660-13-17 2115
EDP# 1917068
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