Diaphragm Vacuum Pump N 828 / N 838
Troubleshooting
Translation of original Operating and Installation Instructions, english, KNF 121249-121517 09/19
51
9. Troubleshooting
DANGER
Extreme danger from electrical shock!
➔
Disconnect the pump power supply before work-
ing on the pump.
➔
Make sure the pump is de-energized and se-
cure.
➔
Check the pump (see Tab. 22 and Tab. 23).
Pump does not transfer
Cause
Fault remedy
Pump not connected to the
mains.
➔
Connect pump to the mains.
No voltage in the mains.
➔
Check room fuse and switch on if necessary.
For pumps with brushless DC
motor:
▪
The motor board’s overcur-
rent protection circuit has
activated.
▪
Maximum temperature of
motor board is exceeded
▪
Maximum blocking time of
the rotor is exceeded
➔
Separate pump from the mains.
➔
Determine and remove the cause of the overcurrent (for
example: improper pressure, liquid in the pump heads).
The pump must be separated from the mains for several
seconds before the electronics will permit restarting.
For pumps with brushless DC
motor:
Wrong polarity of the connection
wires
➔
Separate pump from the mains.
➔
Be aware of right polarity of the connection wires and con-
nect pump.
For pumps with AC motor:
The pump’s thermal switch has
triggered.
➔
Disconnect pump from the mains.
➔
Allow pump to cool.
➔
Identify and eliminate cause of overheating.
Connections or hoses are
blocked.
➔
Check hoses and connections.
➔
Remove blockage.
External valve is closed or filter
is clogged.
➔
Check external valves and filters.
Condensate has connected in
the pump head.
➔
Detach the condensate source from the pump.
➔
Flush the pump (see Chapter 8.2.1).
➔
Install the pump at the highest point in the system.
Diaphragm or valve plates are
worn.
➔
Replace diaphragm and valve plates (see Chapter 8.3).
Tab. 22
