GHC SERIES
OM-05845
PAGE D-1
TROUBLESHOOTING
TROUBLESHOOTING - SECTION D
Review all SAFETY information in Section A.
Before attempting to open or service the
pump:
1. Familiarize yourself with this manual.
2. Allow the pump to completely cool if
overheated.
3. Check the temperature before open
ing any covers, plates, or plugs.
4. Close the suction and discharge
valves.
5. Drain the pump.
TROUBLESHOOTING WITH GAUGES
Most pump or system malfunctions can be detected by installing vacuum suction and discharge pressure
gauges. Read the gauges and refer to the following information for interpretation of the gauge readings. For
additional troubleshooting procedures, see the
TROUBLESHOOTING CHART
.
Vacuum Gauges
HIGH READING
Suction valve closed, suction line blocked,
foot valve jammed, strainer blocked.
Liquid too viscous.
Lift too high.
Suction line undersized.
LOW READING
Air leak in suction line.
End of suction line not submerged.
Pump parts worn or defective.
End clearance too great.
No liquid in pump housing.
ERRATIC READING
Liquid overheated, vaporizing.
Liquid entering intermittently, suction air leak,
end of suction line not submerged.
Vibration from cavitation, misalignment, dam‐
aged parts.
Pressure Gauges
HIGH READING
Liquid too viscous.
Discharge line undersized or too long.
Discharge valve partially closed.
Strainer blocked.
Relief valve pressure set too high.
Thermal changes in liquid.
LOW READING
Relief valve pressure set too low.
Internal valve not seating properly.
Pump bypass partially open.
End clearance too great.
Pump parts worn or defective.
ERRATIC READING
Cavitation.
Liquid entering intermittently, suction air leak,
end of suction line not submerged.
Drive misalignment causing vibration.
