44
5.5 Solve problem
FAULT
SYMPTOM
POSSIBLE CAUSE
SOLUTION
The air handling unit
is noisy.
High air velocity
Air flow too high
Check if the airflow appropriate to
the project value. If not, set it to the
appropriate value.
Duct sections, small for the
application
Check the duct size and revise if
necessary.
Fan too small for the applica-
tion
Contact the AERA Technical Team.
Serpentine with the insufficient
front surface
Contact the AERA Technical Team.
Small vents for application
Check if the airflow appropriate to
the project value. If not, set it to the
appropriate value.
Fan-Motor Noise
Worn or damaged fan wheel
Replace the fan wheel.
Damaged suction funnel
Remove and straighten the funnel,
replace if necessary.
Bush loose
Tighten the bushing, replace if
necessary.
Worn or damaged fan wheel
Replace the fan wheel.
Unbalanced (Balanced) fan
wheel
Contact the AERA Technical Team.
Motor bearing damage/failure
Contact the AERA Technical Team.
Motor cooler damage/failure
Contact the AERA Technical Team.
The foreign item inside the unit
or in the fan
Clean the inside of the unit and fan.
Vibration
Vibrating ducts
Fasten up the ducts.
Vibrating body parts
Fasten up or properly isolate parts
that cause vibration.
A vibration isolator is not placed
between the vibrating parts and
the building.
Put vibration isolator under the
switchboard.
Fan spring insulators loose /
damaged
Check insulators, replace if neces-
sary.
Whistling
Clogging in dampers, vents
Check dampers and vents, correct/
clean if necessary.
General leakage
Check the leak section.
Sharp elbows
Remove sharp elbows install el-
bows of appropriate diameter and
directional blades.
There is a sudden widening or
narrowing of the duct
Replace the expansion/contrac-
tion chambers with the appropri-
ate angle expansion/contraction
chambers.
