Fault Finding - Grundfos CMB PM1 Supplement To Quick Manual

CAUTION
Impurities in water
Minor or moderate
personal injury
- Before the pump is
used for supplying
drinking water, flush
the pump thoroughly
with clean water.
CAUTION
Sharp element
Minor or moderate
personal injury
- Wear protective
gloves.
Fault
1. The green "Power
on" indicator light is
off.
2. The green "Pump
on" indicator light is
on, but the pump
does not start.
3. The pump does not
start when water is
consumed.
The "Pump on"
indicator light is off.
4. Frequent
starts/stops.
8
Cause
a) The fuses in the electrical
installation have blown.
b) The earth leakage circuit breaker or
the voltage-operated circuit breaker
has tripped.
c) No power supply.
d) The PM unit is defective.
a) The power supply to the pump is
disconnected after the PM unit.
b) The motor protection of the pump
has tripped due to overload.
c) The pump is defective.
d) The PM unit is defective.
a) Too big difference in height between
the PM unit and the tapping point.
b) The PM unit is defective.
a) Leakage in the pipes.
b) Leaky non-return valve.
c) A valve close to the PM 1 outlet has
been closed.

8. Fault finding

WARNING
Electric shock
Death or serious
personal injury
- Switch off the power
supply before you start
any work on the
product.
- Make sure that the
power supply cannot
be switched on
accidentally.
Remedy
Replace the fuses. If the new fuses
also blow, check the electrical
installation.
Cut in the circuit breaker.
Contact the power supply company.
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 pipes.
Clean or replace the non-return valve.
Open the valve.