Fantech SHR 1504 Operation Manual - Airflow Balancing
14
AIRFLOW BALANCING
(CONT'D)
1 Cut hole in duct and insert flow
measuring station. Make sure that the
flow measuring station’s air direction
arrow points in the direction of the
airflow. Secure the flow measuring
station with duct tape.
2 Before taking the reading, make sure
that the magnehelic gauge is level and
at 0. Refer to the flow measuring
station’s chart to determine your
unit’s airflow velocity.
3 Adjust the “Supply Air Out” damper
until you reach the desired velocity.
Follow steps 1-3 to adjust the “Exhaust
Air Out” damper, if needed.
Measure
here
Minimum
457mm
(18")
Measure
here
Minimum
457mm (18")
• To avoid airflow turbulence and incorrect
readings, the airflow velocity should be
measured on a section of steel ducting.
Reading should also be taken at a minimum
distance of 457mm (18") from the unit or
elbow. Measurement should also be made
prior to any transition in the duct work so
entire airflow is measured.
MEASURING THE AIRFLOW USING STATION (GRID) METHOD
ADJUSTING AIRFLOWS
A damper is integrated into the Fresh Air to Building collar. This damper replaces the installation of a separate damper
into the Fresh Air to Building ducting line.
The damper-collar is pre-set in the fully opened position. If the procedure requires a reduction in airflow to the fresh air
duct, simply turn positioning knob located on the side of the collar clockwise until desired airflow is obtained. The damper
position can be determined by the orientation of the pointers situated on the side of the damper. The damper is fully open
when the pointers are towards the top of the collar (as shown in picture) and fully closed when they are sideways.
Once procedure is completed, install a piece of tape over positioning knob to avoid any tampering by the home owner.
WARNING! DO NOT TURN POSITIONING KNOB COUNTERCLOCKWISE WHEN DAMPERS ARE FULLY OPENED AS DAMAGE MAY OCCUR TO THE MECHANISM