Fault Finding Chart - Grundfos PM 1 Manual De Instrucciones

12. Fault finding chart

Warning
Before starting work on the pump/PM unit, make sure that the power supply has been switched off
and that it cannot be accidentally switched on.
Fault Cause
1. The green a) The fuses in the electric installation
"Power on"
indicator light
b) The earth leakage circuit breaker or
is off.
c) No power supply.
d) The PM unit is defective.
2. The green a) The power supply to the pump is
"Pump on"
indicator light
is on, but the
b) The motor protection of the pump
pump does not
start.
c) The pump is defective.
d) The PM unit is defective.
3. The pump a) Too big difference in height between
does not start
when water is
b) The PM unit is defective.
consumed.
The "Pump on"
indicator light
is off.
4. Frequent a) Leakage in the pipework.
starts/stops.
b) Leaky non-return valve.
c) A valve close to the PM 1 outlet has
5. The pump a) The pump cannot deliver the
does not stop.
b) A PM unit with too high start
c) The PM unit is defective.
d) The non-return valve is stuck in
6. The red a) Dry running. The pump needs
"Alarm"
indicator light
b) The power supply to the pump is
is permanently
on.
c) The motor protection of the pump
d) The pump is defective.
e) The PM unit is defective.
7. The red a) Cycling. A tap has not been closed
"Alarm"
indicator light
is flashing.
* See service instructions on www.grundfos.com > International website > WebCAPS > Service.
have blown.
the voltage-operated circuit breaker
has tripped.
disconnected after the PM unit.
has tripped due to overload.
the PM unit and the tapping point.
been closed.
necessary discharge pressure.
pressure is installed.
open position.
water.
disconnected after the PM unit.
has tripped due to overload.
entirely after use.
Remedy
Replace the fuses. If the new fuses also blow,
check the electric installation.
Cut in the circuit breaker.
Contact the power supply authorities.
Repair or replace the PM unit.*
Check the plug and cable connections, and
check if the built-in circuit breaker of the
pump is switched off.
Check if the motor/pump is blocked.
Repair or replace the pump.
Repair or replace the PM unit.*
Adjust the installation, or select a PM unit with
a higher start pressure.
Repair or replace the PM unit.*
Check and repair the pipework.
Clean or replace the non-return valve.*
Open the valve.
Replace the pump.
Select a PM unit with a lower start pressure.
Repair or replace the PM unit.*
Clean or replace the non-return valve.*
Check the pipework.
Check the plug and cable connections, and
check if the built-in circuit breaker of the
pump is switched off.
Check if the motor/pump is blocked.
Repair or replace the pump.
Repair or replace the PM unit.*
Check that all taps have been closed.
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