Grundfos Multilift M Montage- Und Betriebsanleitung Seite 27

Fault Cause
3. The pump is a) The level sensor fails. The sensor gives
starting/stopping too
frequently and even if
b) The operating time protection is activated,
there is no inflow.
c) The thermal switch has cut out the pump.
4. Pump starts sometimes a) Test run 24 hours after last operation.
without visible reason.
wrong signal.
the pump and time symbols are flashing, the
red LED is flashing and the display indicates
fault code F011. If the pump runs longer
than 3 minutes, a protection program of the
controller will stop the pump for 3 minutes
and start it again after cooling time.
This operating pattern will continue until a
stop signal from the sensor brings the pump
back to normal operation.
Note: Normal operating time is up to
20 seconds depending on duty point and
effective tank volume.
The pump and thermal switch symbols on
the display are flashing, and the red
indicator light for fault is permanently on.
The fault indication in the display is TEMP
and in the fault code is F007.
Remedy
Clean the level sensor. See section
level sensor.
Check that the outlet valve is open. Check the venting of
the pump housing. If blocked, clean the vent hole. See
fig. 31.
Allow the pump to cool. After cooling, the pump will
restart automatically unless the LC 221 has been set to
manual restarting. See section
If so, the ON-OFF-AUTO selector switch must be
pushed into position OFF ( ) for a short period.
Check the inflow parameters and the non-return valve.
The risk is low, but if the non-return valve flap is leaky,
liquid in the outlet pipe can flow back.
A high number of starts without cooling time in between
over a longer period can cause thermal cut-out.
Consider S3 duty. See section
See also section 10.4 Cleaning the level
No action necessary. It is a safety function that prevents
the shaft seal from seizing up.
10.4 Cleaning the
8.4 Setting of LC 221.
12. Technical data.
sensor.
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