WDM AG Series, Operation Manual

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Operation Manual.
24
4. Insufficient inlet pressure or
suction head.
4. Increase inlet pressure by
adding more water to tank or in-
creasing back pressure by turning
gate valve on discharge line to
partially closed position.
5. Clogged foot-valve, strainer,
or pump. 5. Unclog, clear or replace as
necessary.
Pump overloads driver.
1. Total head lower than pump
rating, unit delivering too much
water.
1. Increase back pressure on
pump by turning gate valve on
discharge line to partially closed
position that will not overload
motor
2. Specific gravity and viscosity
of liquid being pumped different
than the pump rating
2. Consult factory.
Pump vibrates and/ or
makes excessive noise.
1. Mounting plate or
foundation not rigid enough. 1. Reinforce.
2. Foreign material in pump
causing unbalance. 2. Disassemble pump and
remove foreign material..
3. Impeller bent. 3. Replace impeller
4. Cavitation present 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. Piping not supported to
relieve any strain on pump
assembly. 5. Make necessary adjustments.
Pump runs but no fluid.
1. Faulty suction piping (air
leak) 1. Replace faulty suction piping
2. Pump located too far from
fluid source 2. Reposition.
3. Gate valve closed. 3. Open
4. Clogged strainer 4. Clean or replace
6. Discharge height too great 6. Lower the height
7. Fouled impeller.
7. Clean or replace.
8. Faulty mechanical seal
8. Replace
Pump leaks at shaft
1. Worn mechanical seal.
1. Replace
2. Replacement seal not installed
properly.
2. Follow Maintenance
instructions carefully