EBARA 4WN 2-10, Original Instruction Manual, Page: 15 / 51

15
10. Troubleshooting
Fault Cause Action
The pump won’t start
Motor protection switch has been triggered
Remove the plug from the socket for at least one
minute
No power supply
Have the electrical installation checked by a
qualified electrician
Faulty pump / underwater cable Repair or replace the pump / underwater cable
The pump is running but
not pumping any water
The water level in the borehole is too low
Reduce the pumping volume; lower the pump
further or use a pump with a smaller output
Pull the pump out of the borehole and clean or
replace the intake screen
The non-return valve is closed and blocked
Pull the pump out of the borehole and clean or
replace the non-return valve
The non-return valve on the pressure side is closed Open the non-return valve
Motor malfunction Motor malfunction
The pump is faulty Repair or replace the pump
The intake screen is blocked
Pull the pump out of the borehole and clean or
replace the intake screen
he pump is running but
with reduced performance
The pressure pipe is partially blocked by dirt,
leaking or damaged
Clean the pressure pipe, mend the leak or replace
The pump has been immersed too deep into
the borehole and is covered by sand or solids
Reduce immersion depth
The non-return valve is only partially open
Pull the pump out of the borehole and clean or
replace the non-return valve
The intake screen is dirty
Pull the pump out of the borehole and clean or
replace the intake screen
Pump getting too hot Fit the pump with a cooling jacket
Motor malfunction Measure motor current
Pump switching on and off
frequently
(with installed pressure
compensation tank / pressure switch)
Inlet pressure in the compensation tank is too
low
The inlet pressure of the compensation tank should
be about 10 % lower than the pump’s switch-on
pressure
Compensation tank too small
Increase the volume of the compensation tank by
installing a further tank or replace
Compensation tank membrane damaged Replace the compensation tank
Difference between switch-on and switch-off
pressure set on the pressure switch is too low
Increase the pressure difference on the pressure
switch. The switch-on pressure should be about
10 % higher than the pressure of the compensation
tank, but under all circumstances high enough to
ensure that there is an adequate water supply. The
switch-off pressure must not be higher than the
pressure of the compensation tank.
System leaking Seal or repair leak in system.