Fault Finding Chart - Grundfos SCALA Instructions Manual

12.3 Fault finding chart

DANGER
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.
Fault
1. The pump is not
running.
2. The pump is
running.
3. The pump
performance is
insufficient.
14
Cause
a) Power supply failure.
- -
b) The power supply is out of
prescribed voltage range.
Yes
c) The shaft seal has seized up.
No
d) The pump is blocked by
impurities.
No
e) Dry running.
Yes
f) The maximum runtime has been
exceeded.
No
g) The internal non-return valve is
No defective or blocked in completely
or partly open position.
a) Leakage from the pipe system, or
- the non-return valve is not
properly closed due to impurities.
b) Small continuous consumption.
-
c) The temperature of the pump and
- water is below 3 °C.
a) The pump inlet pressure is too
- -
low.
b) The pump is undersized.
-
c) The inlet pipe, the inlet strainer or
- - the pump is partly blocked by
impurities.
d) There is a leakage in the inlet
- -
pipe.
e) There is air in the inlet pipe or the
- -
pump.
f) The required outlet pressure is
- -
too low for the installation.
g) The maximum temperature has
been exceeded and the pump is
Yes
running at reduced performance.
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
installation.
Check the power supply and the pump
nameplate. Reestablish the power
supply within the prescribed voltage
range.
See section 10. Starting up the product
after standstill.
See section 10. 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
reset the alarm.
Clean, repair or replace the non-return
valve. See section 9. 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
installation 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.