Gorman-Rupp Pumps SE1 1/2A3 115V 1P 1483930 and up - Manual (Page 22)

SE SERIES OM−06488
TROUBLESHOOTING PAGE D − 2
Table 1. Trouble Shooting Chart (cont.)
TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
(AUTOMATIC MODE)
(CONT’D.) Defective liquid level sensing de-
vice(s) or control panel. Repair or replace defective unit(s).
OVERLOAD UNIT TRIPS Low or high voltage, or excessive
voltage drop between pump and
control box.
Defective insulation in motor wind-
ings or power cable; defective wind-
ings.
Impeller jammed due to debris or
insufficient clearance.
Bearing(s) frozen.
Measure voltage at control box.
Check that wiring is correct type,
size, and length. (See Field Wiring
Connections, Section B).
Check insulation resistance; check
continuity.
Disassemble pump and check im-
peller.
Disassemble pump and check
bearing(s).
MOTOR RUNS, BUT
PUMP FAILS TO
DELIVER RATED
DISCHARGE Discharge head too high.
Low or incorrect voltage.
Discharge throttling valve partially
closed; check valve installed im-
properly.
Discharge line clogged or re-
stricted; hose kinked.
Liquid being pumped too thick.
Strainer screen or impeller clogged.
Insufficient liquid in sump or tank.
Worn impeller vanes; excessive im-
peller clearance.
Reduce head.
Measure control box voltage, both
when pump is running and when
shut-off.
Open discharge valve fully; check
piping installation.
Check discharge lines; straighten
hose.
Dilute liquid if possible.
Clear clog(s). Stop pump; back flow
may flush away debris.
Stop pump until liquid level rises.
Check impeller and clearance. See
PUMP END REASSEMBLY.
PUMP RUNS WITH
EXCESSIVE NOISE OR
VIBRATION Pumping entrained air.
Damaged or unbalanced impeller.
Discharge piping not properly sup-
ported.
Impeller jammed or loose.
Motor shaft or bearings defective.
Pump cavitation.
Check liquid level in sump; check
position of pump and liquid level
sensing device(s).
Replace impeller.
Check piping installation.
Check impeller.
Disassemble pump and check mo-
tor and bearings.
Reduce discharge head, or restrict
flow on low head applications.