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986GD (Globe) Pump Control Control Valve
2 IOM-A-ACV-986_686 2115
EDP# 1917094
© 2021 Watts
Standard Components
Operation
The Pump Control Valve is designed to minimize the surges asso-
ciated with the starting and stopping of pumps. The valve slowly
opens and closes as required to control pumping related surges.
The pump starts and stops against a closed valve.
Pump Start Up:
When the pump is signaled to start, the 3-Way
Solenoid is energized, directing pressure into the cover chamber
of the 3-way Accelerator Pilot. The Accelerator Pilot allows the
main valve cover chamber to be vented downstream, causing
the valve to open at a controlled rate, gradually admitting pump-
ing pressure into the distribution system. The rate of opening is
controlled by the adjustable opening speed control, which restricts
the speed of fluid and pressure evacuating the main valve cover
chamber. The valve remains open during the pumping cycle.
1
X
X
Y/FC
2
4
6
X
X
7
5
5
CLOSES VALVE
OPENS VALVE
FLOW
3(L)
1
X
X
Y/FC
2
4
6
X
X
7
5
5
CLOSES VALVE
OPENS VALVE
FLOW
3(L)
Installation
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.
3. Install isolation valves upstream and downstream of 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. Connect solenoid wiring leads to desired switching device, using safe, standard electrical practices.
7. Wire the limit switch contacts to the proper relay connections, using safe, standard electrical practices. Adjust the limit switch collar
to the approximate make/break contact position.
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.
Pump Shutdown:
When the pump is signaled to turn off, the 3-Way Solenoid is de-energized, venting the cover chamber of the 3-way
Accelerator Pilot. The Accelerator Pilot allows the main valve cover chamber to be connected to upstream pressure, causing the valve
to close at a controlled rate. The valve slowly begins to close while the pump continues to operate. The closing rate of the valve is
controlled by the adjustable closing speed control, which restricts the speed of fluid and pressure entering the main valve cover cham-
ber. When the valve reaches the closed position, the limit switch is actuated, turning the pump off.
Hydraulic Check Feature:
When the pump is turned off and downstream pressure is greater than upstream pressure, downstream
pressure is admitted to the main valve cover chamber through a check valve in the pilot control system, closing the valve, preventing
reversal of flow.
Manual Operation:
Engaging the Solenoid Manual operator simulates power to the solenoid, manually opening the main valve.
Disengaging the Solenoid Manual operator returns the valve to the closed position.
1 – Main Valve (905GD – Single Chamber)
2 – Model 22-1 Accelerator Control
3 – Limit Switch
4 – 3-Way Solenoid
5 – Check Valve
6 – Adjustable Closing Speed
7 – Adjustable Opening Speed
Y – Y-Strainer
X – Isolation Cocks