English (GB)
39
24. Fault finding
WARNING
Electric shock
Death or serious personal injury
- Switch off the power supply and wait at least five
minutes before you start any work on the product.
Make sure that the power supply cannot be
accidentally switched on.
WARNING
Crushing of feet
Death or serious personal injury
- Use appropriate tools and lifting equipment when
dismantling the product.
Fault Cause Remedy
1. Hydro Multi-E does not run
when started.
a) The actual pressure is higher than or
equal to the setpoint set.
Wait until the pressure has dropped, or lower the
pressure on the outlet side of Hydro Multi-E, and check
that the booster system starts.
b) The power supply is disconnected. Connect the power supply.
c) The circuit breakers have cut out. Correct the fault and cut in the circuit breakers.
d) The internal motor protection is activated. Contact Grundfos.
e) The circuit breaker is defective. Replace the circuit breaker.
f) The motor is defective. Repair or replace the motor.
g) Outlet-pressure sensor fault.
– The outlet-pressure sensor is defective. Replace the outlet-pressure sensor.
– The cable is broken or short-circuited. Repair or replace the cable.
2. Hydro Multi-E starts, but
stops immediately
afterwards. The operating
pressure is not reached.
a) Dry running or no inlet pressure. Check the supply of water to Hydro Multi-E. When the
inlet pressure has been re-established, the pumps will
restart after 15 seconds.
3. Hydro Multi-E is stopped
and cannot restart.
a) Outlet-pressure sensor fault.
– The outlet-pressure sensor is defective. Replace the outlet-pressure sensor. Outlet-pressure
sensors with 0-20 mA or 4-20 mA output signals are
monitored by Hydro Multi-E.
– The cable is broken or short-circuited. Repair or replace the cable.
b) Terminal box unit fault.
– The power supply is disconnected on
pump 1.
Connect the power supply.
– The terminal box is defective. Replace the terminal box of pump 1.
Contact Grundfos.
4. Unstable water supply
from Hydro Multi-E (only
applies to very low
consumption).
a) The inlet pressure is too low. Check the inlet pipe and possible inlet strainer.
b) The inlet pipe or pumps are partly blocked
by impurities.
Clean the inlet pipe or pumps.
c) The pumps suck air. Check the inlet pipe for leakages.
d) The outlet-pressure sensor is defective. Replace the outlet-pressure sensor.
5. Pumps are running, but
deliver no water.
a) The inlet pipe or pumps are blocked by
impurities.
Clean the inlet pipe or pumps.
b) The non-return valve is blocked in the
closed position.
Clean the non-return valve. The non-return valve must
move freely.
c) The inlet pipe is leaky. Check the inlet pipe for leakages.
d) Air in inlet pipe or pumps. Vent the pumps. Check the inlet pipe for leakages.
6. Hydro Multi-E is unable to
reach the setpoint.
a) The cable is broken or short-circuited
(GENIbus communication between pump
1 and pump 2/3).
Repair or replace the cable.
b) Pump 2 or 3 is out of operation. Connect the power supply to the pump and check the
pump condition.
7. Leakage from a shaft seal. a) The shaft seal is defective. Replace the shaft seal.
b) CRE and CRIE pumps:
The height adjustment of the pump shaft
is inaccurate.
Re-adjust the shaft height.
8. Noise. a) The pumps are cavitating. Clean the inlet pipe or pumps and possibly the inlet
strainer.
b) CRE and CRIE pumps:
The pumps do not rotate freely (frictional
resistance) due to inaccurate height
adjustment of the pump shaft.
Re-adjust the shaft height. See the CR, CRI, CRN
installation and operating instructions supplied with
Hydro Multi-E.
9. Very frequent starts and
stops.
a) Wrong diaphragm tank precharge
pressure.
Check the precharge pressure.
b) The difference between start and stop
pressures is too small.
Note: This situation will only arise if
emergency operation is installed.
Increase the differential pressure setting on each
pressure switch.
To Next Page
Loading...
General