
Troubleshooting | 11
Instruction Manual COBRA NC 0500 B_EN_en
27 | 36
11
Troubleshooting
DANGER
Live wires.
Risk of electrical shock.
●
Electrical installation work must only be executed by qualified personnel.
CAUTION
Hot surface.
Risk of burns!
●
Prior to any action requiring touching the machine, let the machine cool down first.
Problem
Possible Cause
Remedy
The machine does not start.
The motor is not supplied with
the correct voltage.
●
Check the power supply.
The rotors are jammed or
seized.
●
Turn the screw rotors
manually from the rotor
access plug (PMR).
●
Repair the machine (contact
Busch).
Solid foreign matter has
entered the machine.
●
Remove the solid foreign
matter or repair the
machine (contact Busch).
●
Install an inlet filter if
necessary.
The temperature switch (TS)
reached the switch point.
●
Let the machine cool down.
●
See problem “The machine
runs too hot”.
Corrosion in the machine from
remaining condensate.
●
Repair the machine.
The motor is defective.
●
Replace the motor.
The machine does not reach
the usual pressure on the
suction connection.
Suction or discharge lines too
long or section diameter too
small.
●
Use larger diameter or
shorter lines.
●
Seek advice from your local
Busch representative.
Process deposits on the
pumping components
●
Flush the machine.
The machine runs in the wrong
direction.
●
Check the direction of
rotation, see Wiring
Diagram Three-Phase
Motor.
Internal parts are worn or
damaged.
●
Repair the machine (contact
Busch).