NCF fan
7 Troubleshooting
The following chart lists the main problems that may be encountered:
Problem
Cause
Solution
No electrical connection
Check that the motor and/or com-
mand inverter is connected to the
electrical power supply line and is
correctly powered
Motor malfunction
Check internal connections and
motor components and replace
them if necessary
No connection between command
inverter and motor
Check for correct connection
between inverter and motor
NCF fan does not start
Command inverter malfunction
Check internal inverter circuits
and components and replace them
if necessary
Rotation speed too low
Increase rotation speed
Openings or ducting partially
blocked
Eliminate obstruction
Check the position of regulation
organs
Impeller partially blocked
Eliminate obstruction
Resistance pressure of system
higher than the design value
Check the resistance pressure
value of the system
Power absorption is much lower
than the design value
Fluid density lower than the inten-
ded value
Check the fluid density value
Rotation speed too high
Reduce rotation speed
Resistance pressure of system
lower than the design value
Check the resistance pressure
value of the system
Incorrect impeller rotation direc-
tion
Check impeller rotation direction
and orientation
Pre-rotation of air in opposite dir-
ection to fan rotation
Check minimum installation dis-
tances (paragraph 5.1.1) or correct
orientation of intake with pre-dis-
tributors
Fluid density higher than the in-
tended value
Check the fluid density value
Power supply to the motor with
voltage lower than shown on the
identification plate
Check for the correct voltage of
the power supply to the motor
Too high power absorption
Defects in motor windings
Check for correct motor operation
Insufficient pressure
Rotation speed too low
Increase rotation speed
EN
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