Install Instructions

English (US)
38
16.3 Fault finding
A fault indication can be reset in one of the following ways:
• When the fault cause has been eliminated, the pump will
revert to normal duty.
• If the fault disappears by itself, the fault indication will
automatically be reset.
• The fault cause will be stored in the pump alarm log.
Warning and alarm codes Fault
Automatic reset
and restart?
Corrective actions
Pump communication fault (10)
Alarm
Communication fault between
different parts of the
electronics.
Yes
Replace the pump, or call GRUNDFOS
SERVICE for assistance.
Check if the pump is running in turbine operation.
See code (29) Forced pumping.
Forced pumping (29)
Alarm
Other pumps or sources force
flow through the pump even if
the pump is stopped and
switched off.
Yes
Switch off the pump on the main switch. If the
light in the Grundfos Eye is on, the pump is
running in forced-pumping mode.
Check the system for defective non-return valves
and replace, if necessary.
Check the system for correct position of
non-return valves, etc.
Undervoltage (40, 75)
Alarm
Supply voltage to the pump
too low.
Yes
Check that the power supply is within the
specified range.
Blocked pump (51)
Alarm
The pump is blocked. No
Dismantle the pump, and remove any foreign
matter or impurities preventing the pump from
rotating.
Dry running (57)
Alarm
No water at the pump inlet or
the water contains too much
air.
No
Prime and vent the pump before a new start-up.
Check that the pump is operating correctly. If not,
replace the pump, or call GRUNDFOS SERVICE
for assistance.
High motor temperature (64)
Alarm
Temperature in stator windings
too high.
No
Check the winding resistance according to the
MAGNA3 service instructions.
Internal fault (72, 84, 155, 157)
Warning/alarm
Internal fault in the pump
electronics.
Yes
Replace the pump, or call GRUNDFOS
SERVICE for assistance.
Overvoltage (74)
Alarm
Supply voltage to the pump
too high.
Yes
Check that the power supply is within the
specified range.
Communication fault, twin-head
pump (77)
Warning
Communication between
pump heads disturbed or
broken.
Yes
Check that the second pump head is powered or
connected to the power supply.
Internal sensor fault (88)
Warning
The pump is receiving a signal
from the internal sensor which
is outside the normal range.
Yes
Check that the plug and cable are connected
correctly in the sensor. The sensor is located on
the back of the pump housing.
Replace the sensor, or call GRUNDFOS
SERVICE for assistance.
External sensor fault (93)
Warning
The pump is receiving a signal
from the external sensor which
is outside the normal range.
Yes
Does the electrical signal set (0-10 V or 4-20 mA)
match the sensor output signal?
If not, change the setting of the analog input, or
replace the sensor with one that matches the
setup.
Check the sensor cable for damage.
Check the cable connection at the pump and at
the sensor. Correct the connection, if required.
The sensor has been removed, but the analog
input has not been disabled.
Replace the sensor, or call GRUNDFOS
SERVICE for assistance.
Caution
If the power supply cable is damaged, it must be replaced by the manufacturer, the manufacturer's service partner or
a similarly qualified person.