Toro 900 Series Installation, Operation & Maintenance Manual page 2

Control Loop
Number
1 Main Valve
2 Inline Finger Filter
3 2-Way Multi-Purpose Pilot
Troubleshooting
Problem
Valve does not open. Inlet pressure is too low.
Pilot's adjusting screw is
completely closed.
Blocked pilot.
Valve does not close. Blocked inline finger filter (2). Disconnect the upstream
Debris on the sealing seat.
Damaged diaphragm.
Non-uniform
Blocked or damaged pilot
Regulation.
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Toro Ag
1588 N. Marshall Avenue,
El Cajón, CA 92020-1523,
Tel.: + 1 (877) 373-0087 + 1 (619) 596-2495
Fax: + 1 (800) 892-1822 + 1 (619) 258-9973
toro.com
ALT375
03/24
Description
Cause
Check the inlet pressure.
Check the screw position.
No water is coming out of
pilot port #0.
tube. No firm water stream.
Valve is constantly
discharging a small amount
of water.
Continuous water discharge. Replace the diaphragm.
Unstable pressure
upstream of the valve
USA
Check
Increase inlet pressure.
Rotate anti-clockwise. Continue until the valve begins to
open.
Dismantle and clean pilot ports. Replace pilot if the
problem not solved.
Clean or replace the filter.
Dismantle, clean, and check that the parts are not
damaged.
Dismantle and clean. Replace the pilot if the problem
persists.
Solution