Fault Finding Chart - Grundfos SCALA2 Instructions Manual

14.3 Fault finding chart

DANGER
Fault
The pump is not
running.
The pump is run-
ning.
The pump per-
formance is insuf-
ficient.
22
Cause
- - Power supply failure.
The power supply is out of prescribed
Yes
voltage range.
No The shaft seal has seized up.
No The pump is blocked by impurities.
Yes Dry running.
The maximum runtime has been ex-
No
ceeded.
The internal non-return valve is defec-
No tive or blocked in completely or partly
open position.
Leakage from the pipe system, or the
- non-return valve is not properly closed
due to impurities.
- Small continuous consumption.
The temperature of the pump and wa-
-
ter is below 3 °C.
- - The pump inlet pressure is too low.
- The pump is undersized.
The inlet pipe, the inlet strainer or the
- -
pump is partly blocked by impurities.
- - There is a leakage in the inlet pipe.
There is air in the inlet pipe or the
- -
pump.
The required outlet pressure is too low
- -
for the installation.
The maximum temperature has been
Yes exceeded and the pump is running at
reduced performance.
Electric shock
Death or serious personal injury
‐
Before starting any work on the product, make sure
that the power supply has been switched off and that it
cannot be accidentally switched on.
Remedy
Switch on the power supply.
Check the cables and cable connections
for defects and loose connections and
check for blown fuses in the electrical in-
stallation.
Check the power supply and the pump
nameplate. Reestablish the power supply
within the prescribed voltage range.
See section Starting up the product after
standstill.
See section Starting up the product after
standstill.
Contact Grundfos Service if the problem
persists.
Check the water source, and prime the
pump.
Check the installation for leakage and re-
set the alarm.
Clean, repair or replace the non-return
valve. See section Servicing the product.
Check and repair the pipe system, or
clean, repair or replace the non-return
valve.
Check the taps and reconsider the usage
pattern (ice machines, water evaporators
for air-conditioning, etc.).
Consider protecting the pump and the in-
stallation against frost.
Check the inlet conditions of the pump.
Replace the pump with a bigger pump.
Clean the inlet pipe or the pump.
Repair the inlet pipe.
Prime the inlet pipe and the pump.
Check the inlet conditions of the pump.
Increase the pressure setting (arrow up).
Check the cooling conditions. Protect the
pump against direct sunlight or any nearby
heat sources.