Crane Crown B12 Series, Installation And Operation Manual

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10
TROUBLE SHOOTING
CAUTION !
Always disconnect the pump from the electrical power source before handling.
If the system fails to operate properly, carefully read instructions and perform maintenance recommendations.
SYMPTOM POSSIBLE CAUSE(S) CHECK
A. Pump not primed - Vacuum
gauge reading less than normal
1. Air leak in suction side of system. a. Threaded joints in suction line for tight fi t
b. Gasket in suction line for tight fi t
c. O-rings in case cover for nicks or cuts
d. Mechanical seal for air leaks
e. Bottom drain plug for air leaks
f. O-rings in pump side for nicks or cuts
g. Vacuum gauge may be leaking internally
2. Air bleed line blocked, or Air bleed valve
closed.
a. Check line or valve
3. Insuffi cient liquid in case
a. Pump case for water level
b. Suction check valve for obstructions or deterioration
4. Operating speed to low
a. Belts for proper tension
b. Motor for low voltage
5. Plugged pump
a. Impeller for lodge foreign material
b. Vent line for stoppage
6. Mechanical defects
a. Impeller - volute for proper clearance
b. Impeller and volute for damage
c. Pump for worn parts
B. Pump not priming - Vacuum
gauge reads more than normal
1. Suction side of system clogged
a. End of suction line for obstructions
b. Suction pipe for obstructions
c. Suction check valve for obstructions
C. Pump primes - Vacuum gauge
reads normal, discharge gauge
reads lower than normal
1. Small air leak in suction side of system
a. For excessive air in discharge line
b. Refer to A-1, a through g
2. Pump speed too slow
a. Belts for proper tension
b. Motor for low voltage
3. Mechanical defects
a. Impeller - volute for proper clearance
b. Impeller and volute for damage
c. Pump for worn parts
D. Pump primes - Vacuum gauge
reads near normal, Discharge
gauge reads higher than normal
1. Plugged discharge
a. Discharge line for obstructions
b. Discharge valves to insure proper operation
E. Pump looses prime when shut
off - Vacuum gauge recedes to
zero
1. Check valve leaking
a. Check valve for obstructions or deterioration
b. Leak in suction pipe threads or fl anges
c. Water level bubbler control line too close to suction pipe
d. The infl uent liquid for chuming air into the sump and
entering the suction pipe