7
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)
Little or no discharge
and unit will not prime
1.
Casing not fi lled with water
2. Total head too high
3.Suction head higher than pump designed for
4. Impeller partially or completely plugged
5. Hole or leak in suction line
6. Foot-valve too small
7. Impeller damaged
8. Foot-valve or suction line not submerged
deep enough in water; pulling air
9. Insuffi cient inlet pressure or suction head
10. Suction piping too small
11. Casing gasket leaking
12. Suction or discharge line valves closed
13. Piping is fouled or damaged
14. Clogged strainer or foot-valve
15. Incorrect engine speed
1.
Fill pump casing. Using a foot-valve will extend
pump life and facilitate immediate priming
2. Shorten suction head
3. Lower suction head, install foot-valve and prime.
4. Disassemble pump and clean out impeller
5. Repair or replace suction line
6. Match foot-valve to piping or install one size
larger foot-valve
7. Disassemble pump and replace impeller
8. Submerge lower in water
9. Increase inlet pressure by adding more water to
tank or increasing back pressure by turning gate
valve on discharge line partially closed position
10. Increase pipe size to pump inlet size or larger
11. Replace
12. Open
13. Clean or replace
14. Clean or replace
15. Increase speed
Loss of suction after
satisfactory operation
1. Air leak in suction line
2. When unit was last turned off, water siphoned
out of pump casing
3. Suction head higher than pump designed for
4. Insuffi cient inlet pressure or suction head
5. Clogged foot-valve, strainer, or pump
6. Defective wearplate(s)
1. Repair or replace suction line
2. Refi ll (reprime) pump casing before restarting
3. Lower suction head, install foot-valve and primer
4. Increase inlet pressure by adding more water to
tank or increasing back pressure by turning gate
valve on discharge line to partially closed position.
5. Unclog, clear or replace as necessary.
6. Replace.
Pump overloads driver
1. Total head lower than pump rating, unit
delivering too much water
2. Specifi c gravity and viscosity of liquid being
pumped different than the pump rating
3. Speed to high
1. Increase back pressure on pump by turning gate
valve on discharge line to partially closed
position that will not overload motor.
2. Consult factory.
3. Check and correct. lower speed
Pump vibrates and/or
makes excessive noise
1. Mounting plate or foundation not rigid enough
2. Foreign material in pump causing unbalance
3. Impeller bent
4. Cavitation present
5. Piping not supported to relieve any strain on
pump assembly
1. Reinforce.
2. Disassemble pump and remove.
3. Replace impeller.
4. Check suction line for proper size and check
valve in suction line if completely open, remove
any sharp bends before pump and shorten
suction line.
5. Make necessary adjustments.
Pump runs but no fl uid
1. Faulty suction piping (air leak)
2. Pump located too far from fl uid source
3. Gate valve closed
4. Clogged strainer
5. Fouled foot-valve
6. Discharge height too great
7. Fouled impeller
8. Faulty mechanical seal
1. Replace
2. Replace
3. Open
4. Clean or replace
5. Clean or replace
6. Lower the height
7. Clean or replace.
8. Replace
Pump leaks at shaft
1. Worn mechanical seal
2. Replacement seal not installed properly
1. Replace
2. Follow Maintenance instructions carefully
Summary of Contents for 2020HC
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