ENVIRO-TEC
43
FORM ET115.24-NOM11 (118)
Excessive fan
noise
Motor mounting bolts loose
Tighten motor mounting bolts.
Motor shaft bent
Replace motor.
Motor bearing end of life
Disconnect power from unit. Verify motor rotates freely
by hand with blower disconnected. Note: EC motors
may not rotate freely as the rotor aligns with the stator
magnets.
Motor overloaded
Verify static pressure per system design. Use amp meter
to verify motor amps. Disconnect power to unit. Verify
motor rotates freely with power disconnected. If not,
replace motor.
Motor end of life
Use amp meter to verify motor amps. Replace motor.
Dirty filters
Verify filters. Replace as needed.
Obstructed airflow
Verify blower is unobstructed. Verify no duct obstruction.
Verify dampers are full open.
Improper duct connections
Verify ductwork is installed per SMACNA and ASHRAE
guidelines.
Static pressure too low
Verify static pressure per system design.
Improperly balanced system
Verify airflow through connected ductwork
Fan wheel rubbing on fan
housing
Align wheel in housing.
Loose fan wheel
Align and tighten.
Damaged fan wheel
Inspect fan wheel to verify fins are not bent. Replace
blower as needed.
Imbalanced fan wheel
Inspect fan wheel. Replace as needed.