Toro Ag 900 Series Instruction And Operation Manual

Ag
File Name: 900 Series Valve IOM
Pressure Sustaining Valve
Description
The pressure-sustaining valve installed in-line sustains minimum back pressure, protects the
pump from overloading during line filling, maintains back pressure during filter flushing, and
may be controlled by a 3-way pilot. The spring-loaded membrane of the pilot is sensitive to
upstream pressure and opens the valve when the inlet pressure exceeds the pilot set pressure.
The valve modulates in response to the electric signal.
Installation
1)
The valve can be installed both horizontally or vertically.
2)
Ensure enough space nearby for installation and adjustment.
3)
Flush the pipeline before installing the valve, to ensure clean water flow.
4)
The line flow direction should match the arrow on the valve.
5)
Inspect the valve post installation for any loose or damaged fittings.
6)
Install a pressure gauge upstream or use a pressure checkpoint on the valve to set the desired pressure.
7)
For maintenance, installation of isolation valves upstream and downstream is recommended.
8)
Cross-check solenoid specifications with design requirements and solenoid/coil labels.
Initial Startup and Adjustment
1) At the system's initial start, ensure the upstream and downstream isolation valves are fully closed (if installed).
2) Allow the valve to open by using the solenoid manual override or by energizing the solenoid (for a normally closed valve) or de-energizing (for a
normally open valve) and pulse signal for a latching solenoid.
3) Fully open the upstream isolation valve or start the pump and check for any leakage through valve connections and fittings.
4) The valve is factory set at 3 bars (or as per design definitions).
5) If the set pressure is either different from the design or the requirements have been changed, follow the steps described below.
Unscrew the lock nut fully and turn the adjusting screw of pilot in a clockwise direction until the lock nut and screw head touch the pilot's
a)
bonnet.
b) Slowly open the downstream isolation valve to allow little flow downstream (make sure there is moderate flow demand).
c) Now rotate the adjusting screw anti-clockwise and allow the valve to respond until the upstream pressure reaches the required set
pressure and water starts to flow through the pipeline. Tighten the lock nut on the pilot.
6) Now gradually open the downstream isolation valve until it is fully opened (or increase flow demand to the nominal flow intended) .
7) Ensure the upstream set pressure is met and maintained automatically with the valve. Re-adjust if necessary. 8). For manual operation, turn the 3-
way manual selector to:
"CLOSE" for closing the valve shut.
a)
"OPEN" for opening the valve fully open.
b)
"AUTO" for regulating mode
c)
Maintenance
1). Periodic inspection of the valve should be done regularly to check for any damage or leakage through valve connection and fittings.
2). Inspect and clean the in-line finger filter as water quality dictates. This should be done once every few months.
3). Keep a check on valve performance by checking the upstream pressure gauge periodically adjust if required.
Issue Date: October 12, 2021
with Electric Control
Revision: January 6, 2023