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Model CDMD
I&O IN-159
have been removed prior to
working on the pump.
Inverting pump with liquid
in it could cause liquid to get
into motor bearings and
cause damage. Before
disassembling be certain all
liquid is removed from the
pump.
TROUBLESHOOTING
1. Pump fails to build pressure
:
Check for:
a. Pump not primed.
b. Incorrect rotation.
c. Driver speed too low.
d. Suction line restricted.
e. Driver failure.
f. Plugged or damaged
impeller.
g. Pump or impeller
undersized.
h. Pump cavitation.
I. Impeller rubbing volute.
2. Pump fails to provide
enough flow.
Check for:
a. System resistance too
high.
b. Pump undersized.
c. Pump not primed.
d. Driver speed too low.
e. Poor suction conditions
f. Impeller rubbing volute
due to improper
installation.
g. Pump cavitation.
h. Plugged or damaged
impeller.
3. Excessive noise or
vibration during operation.
Check for:
a. Motor bearing failing.
b. Pump cavitating.
c. Impeller rubbing volute.
4. Leaking mechanical seal.
Check for:
a. Improper assembly.
b. Worn or cracked seal
faces.
c. Abrasive material build
up around seal.
d. Liquid flashing at seal
faces (temp too high).
e. Seal pressure rating too
low for the service.
f. Chemical attack of seal
parts.
g. Seal operated dry or with
a liquid having poor
lubricating properties.
4. Pump gradually loses
pressure and head.
Check for:
a. Increasing temperature
causing cavitation or
liquid vaporization.
b. Driver failure.
c. Suction lift too high.
d. Air entering suction line.
5. Motor/pump overheating.
Check for:
a. Excessive flow and amp
draw. (Throttle discharge)
b. Low voltage or
frequency.
c. Flow too low with
resulting heat rise.
d. Bearing failure.
e. System temperature too
high.
(CDMD-159\I&O)
