Toro 900 Series - Troubleshooting; Valve Operation Problems

Control Loop
Number
Description
1
Main Valve
2
Inline Finger Filter
3
2-Way Multi-Purpose Pilot
Troubleshooting
Problem
Cause
Check
Solution
Valve does not open.
Inlet pressure is too low.
Check the inlet pressure.
Increase inlet pressure.
Pilot's adjusting screw is
completely closed.
Check the screw position.
Rotate anti-clockwise. Continue until the valve begins to
open.
Blocked pilot.
No water is coming out of
pilot port #0.
Dismantle and clean pilot ports. Replace pilot if the
problem not solved.
Valve does not close.
Blocked inline finger filter (2).
Disconnect the upstream
tube. No firm water stream.
Clean or replace the filter.
Debris on the sealing seat.
Valve is constantly
discharging a small amount
of water.
Dismantle, clean, and check that the parts are not
damaged.
Damaged diaphragm.
Continuous water discharge.
Replace the diaphragm.
Non-uniform
Regulation.
Blocked or damaged pilot
Unstable pressure
upstream of the valve
Dismantle and clean. Replace the pilot if the problem
persists.
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Toro Ag
1588 N. Marshall Avenue,
El Cajón, CA 92020-1523, USA
Tel.: + 1 (877) 373-0087 + 1 (619) 596-2495
Fax: + 1 (800) 892-1822 + 1 (619) 258-9973
toro.com
ALT375
0 4/24
Manual 900 Series Quick Relief Valve