Table 4-3. Unit Troubleshooting - CONT.
Test or Inspection
1. FAILURE OF SPRAY PUMP TO PRIME.
Step 1. Check for restricted intake or discharge lines. Open all lines and valves and check for jammed or
Clean or replace lines (para 4-123) or valves (para 4-124) as necessary.
Step 2. Check for air leak in intake line.
Replace line (para 4-123).
Step 3. Defective pump.
Replace pump or repair as needed; check for ruptured diaphragm, defective check valve,
crack in pump housing, debris in pump head (para 4-120).
2. SPRAY PUMP MOTOR FAILS TO TURN ON.
Step 1. Pump or equipment not plugged in electrically. Check for loose wiring connection.
Replace or repair as needed (para 4-120).
Step 2. Check switch.
Repair or replace as needed (para 4-64).
Step 3. Check motor.
Repair or replace as needed (para 4-120).
3. LOW SPRINKLER FLOW AND PRESSURE.
Step 1. Check for air leak at pump intake.
Tighten fittings or replace lines as needed (para 4-123).
Step 2. Check for dirt or debris inside pump or plumbing.
Clean pump and system (para 4-120 and 4-123).
Step 3. If excessively noisy, check for worn pump bearing.
Replace pump or bearing as necessary (para 4-120).