7. Troubleshooting
7.1 Troubleshooting
Even if the same failure occurs, the cause and action may be different. In addition, there may be
two or more causes.
If the cause and action cannot be determined using the following table, stop the operation
immediately and contact a specialist company or the service center specified by the
manufacturer.
Failure Cause
Action
The bearing
temperature
is high.
Excess or lack of grease
Poor fit between the bearing inner ring
and the main shaft
Poor connection between the outer ring
and bearing case of the bearing
Deterioration of grease, or entry of
moisture
Excessive tension of the V-belt
Adjust it to the proper amount.
Replace the main shaft.
Replace the bearing.
Change the grease. Replace the bearing.
Readjust the V-belt tension.
Strong
vibration
Corrosion or wear in the impeller, or
foreign matter on the impeller
Poor connection between the impeller
boss and the main shaft
Unbalance of the V-belt pulley
Bend of the main shaft
Contact between the rotor and casing
Resonance caused by insecure
foundations
Insufficient tightening of the mounting bolt
Damage to the bearing
Remove the foreign matter adhered to the
impeller. Correct the balance of the
impeller.
Replace the impeller or the main shaft.
Replace the V-belt pulley, or correct the
balance of the pulley.
Replace the main shaft.
Reassemble the casing.
Reinforce the foundations.
Retighten the bolt and nut.
Replace the bearing.
Abnormal
noise
Damage to the bearing
Intake of foreign matter
Contact between the rotor and casing
Contact with the belt guard
Replace the bearing.
Inspect the inside of the casing.
Avoid the contact between the rotor,
casing, and air intake.
Readjust the V-belt tension,
Low
performance
Decrease in rotational speed or
frequency
Reverse rotation
Corrosion or wear in the impeller, or
foreign matter on the impeller
Clogging of the intake filter
Failure in opening/closing of the damper
Dust deposited inside the casing and duct
Excessive resistance
Errors in calculating the specific weight of
gas
Regulate the power supply.
Swap the wires of the motor.
Clean, repair, or replace the impeller.
Clean the intake filter.
Repair the damper.
Clean the place.
Consider installing a booster fan, or
replace the V-belt pulley.
Measure the specific weight, or perform a
gas analysis.
Motor
overload
Insufficient resistance
Excessive rotation
Errors in calculating the specific weight of
gas
Adjust it with the damper.
Replace the V-belt pulley.
Reduce the rotational speed.
7-1
