Grundfos LON Module Instrucciones De Montaje página 8

Fault Cause
Noise in the Air in the system.
system.
The pump flow is too high.
The green indi-
cator light is
The pressure is too high.
on.
The red indica-
tor light is off.
Noise in the Air in the pump.
pump.
The inlet pressure is too low. Increase the inlet pressure and/or
The green indi-
cator light is
on.
The red indica-
tor light is off.
Insufficient The pump performance is
heat in some too low.
places in the
heating sys-
tem.
The pump The pump has been cut out
does not run. by the thermal overload
The green indi- switch due to high liquid
cator light is temperature or blocked ro-
off. tor.
The red indica-
tor light is on.
The speed switch module
and the basic module are
not of the same type. One is
a three-phase module and
the other is a single-phase
module.
The speed switch module
has not been fitted.
Electricity supply failure
(overvoltage/undervoltage).
Missing phase (only three-
phase pumps).
Fault in electronics.
Remedy
Vent the system.
Reduce the pump performance
(change to lower speed).
Reduce the pump performance
(change to lower speed).
Vent the pump.
check the air volume in the expansion
tank, if installed.
Increase the pump performance
(change to higher speed), if possible,
or replace the pump with a pump with
a higher flow.
Check that the liquid temperature falls
within the specified range. The pump
starts automatically after cooling.
Note: If the thermal overload switch
has cut out the pump five times within
one hour, the pump can only be re-
started after the electricity supply has
been switched off.
Replace one of the modules so that it
is suitable for the pump type (single-
phase or three-phase).
Switch off the electricity supply by
means of the external mains switch
and fit the speed switch module.
Check that the electricity supply falls
within the specified range.
Check fuses and connections.
Replace the modules in the terminal
box. Contact GRUNDFOS.
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