■
Sprinkler Assembly
PROBLEM
POSSIBLE CAUSE – CORRECTIVE ACTION
SPRINKLER WON'T ROTATE
(a)
Debris wedged between stator and turbine.
– Remove obstruction.
(b)
Drive assembly defective.
– Replace drive assembly.
(c)
Nozzle base assembly defective.
– Replace nozzle base assembly.
HEAD STICKS UP
(a)
Dirt in riser assembly.
– Flush out. (See Flushing Procedure on page 11.)
(b)
Damaged or missing return spring.
– Replace.
(c)
Damaged riser.
– Replace.
POOR DISTRIBUTION PATTERN
(a)
Nozzle plugged with debris.
– Clean or replace nozzle.
(b)
Nozzle orifice damaged.
– Replace nozzle.
(c)
Low operating pressure.
– Determine why system overloaded and correct.
■
Main Valve
PROBLEM
POSSIBLE CAUSE – CORRECTIVE ACTION
VALVE WON'T CLOSE
(a)
Continuous 24 VAC to sprinkler.
(Electric )
– Check controller for voltage source.
(b)
Leak in pilot valve assembly.
– Replace pilot valve assembly.
(c)
Plugged supply screen on piston.
– Clean or replace screen.
(d)
Manual control selector on pilot valve assembly turned to "ON" position.
– Turn to "AUTO" position.
(e)
Plunger movement restricted.
– Inspect and clean or replace.
(f)
Valve cylinder misaligned with sprinkler body communication tube.
– Remove valve assembly and install correctly.
(g)
Foreign object keeping valve from seating.
– Remove, clean and check valve for damage. Replace if necessary.
(h)
Damaged piston seal or piston assembly.
– Replace valve assembly.
VALVE WON'T CLOSE
(a)
Leak in control tubing.
(Hydraulic)
– Isolate and repair.
(b)
Pilot valve leak in controller.
– Confirm by observing constant dripping from discharge line of controller.
Refer to Controller Service Manual.
(c)
Valve cylinder misaligned with sprinkler body communication tube.
– Remove valve assembly and install correctly.
(d)
Foreign object keeping valve from seating.
– Remove, clean and check valve for damage. Replace if necessary.
(e)
Damaged piston seal or piston assembly.
– Replace valve assembly.
VALVE WON'T OPEN
(a)
Control (field) wires severed.
(Electric)
– Isolate and repair.
(b)
No power to controller.
– Establish controller power.
(c)
No power from controller to solenoid.
– Check for blown fuse and replace.
(d)
Manual control selector on pilot valve assembly turned to "OFF" position.
– Turn to "AUTO" position.
(e)
Pilot valve solenoid inoperative.
– Remove and replace.
(f)
Pilot valve plunger movement restricted.
– Inspect, clean and/or replace.
(g)
No supply from main valve.
– Debris in control tube, main valve assembly and/or communication passages in
body. Flush thoroughly.
5
