Colasit CMVpro 125, Operating Instructions Manual, Page: 59 / 76

Repair | 11
Operating instructions CMVpro 125-400 | Version 1-en 59 / 76
Fault Possible cause Fault discovery Remedy
Grinding noise
coming from
the impeller. Casing too tight. Check distance and
alignment of ductwork
to fan connection. Adjust ductwork dis-
tance and connection
(sleeves) appropri-
ately.
Ductwork connected to
fan without sleeves. Connect ductwork to
fan with sleeves
_
Chap. 6.8 [
}
35].
Impeller misaligned. Can the impeller be
moved axially on the
motor shaft? Impeller position
_ Chap. 11.8 [ } 65]
Clamp down clamping
adapter
_
Chap. 11.5 [
}
61].
Deposits or foreign ob-
jects between impeller
and inlet cover. Determine grinding
point.
Check with feeler
gauge.
Remove deposits or
foreign objects
_
Chap. 10.3.3 [
}
53].
Impeller defect. Visual inspection. Replace impeller
_ Chap. 11.5 [ } 61].
Audible sound
from bearings. Bearing damage. Auditory inspection. Replace motor bear-
ings or exchange mo-
tor
_
Chap. 11.7 [
}
64].
End of service life
reached.
Bearing damage due
to electrical discharge
machining (bearing
currents). Measure voltage be-
tween the motor shaft
and casing of the elec-
tric motor. Interference suppres-
sion measures with FC
operation; see FC
manufacturer’s guid-
ance.
Use current-insulated
roller bearings or ce-
ramic hybrid bearings.
Excessive
leakage at im-
peller hub. Overpressure opera-
tion of the fan (without
optional hub seal). Pressure measure-
ment. Operate fan at nega-
tive pressure.
Install optional hub
seal.
Hub seal worn or de-
fective. Visual inspection. Replace sealing
_ Chap. 11.9 [ } 66].