Lifebreath CAF-02-MB User Manual
This is an example for determining the airflow in a
6" duct. The Pitot tube reading was 0.025
inches of water. From the chart, this is 640 feet
per minute.
6" duct. The Pitot tube reading was 0.025
inches of water. From the chart, this is 640 feet
per minute.
The 6" duct has a cross sectional area of:
=
[
3.14 x (6"÷12)
2
]
÷4
= 0.2 square feet
The airflow is then:
640 ft./min. x 0.2 square feet = 128 cfm
640 ft./min. x 0.2 square feet = 128 cfm
For your convenience, the cross sectional area of
some common round duct is listed below:
DUCT DIAM. (inches) CROSS SECTION AREA (sq. ft.)
some common round duct is listed below:
DUCT DIAM. (inches) CROSS SECTION AREA (sq. ft.)
5.0
.14
6.0
.20
7.0
.27
The accuracy of the airflow reading will be
affected by how close to any elbows or bends the
readings are taken. Accuracy can be increased by
taking an average of multiple
readings as outlined in the literature supplied with
the Pitot tube.
affected by how close to any elbows or bends the
readings are taken. Accuracy can be increased by
taking an average of multiple
readings as outlined in the literature supplied with
the Pitot tube.
26
BUILT-IN
BALANCING
DAMPERS
BACK DRAFT
DAMPER
OUTSIDE
HOOD
INSULATED PIPE
WITH VAPOUR
BARRIER
Note: For best results keep Pitot tube
well away from dampers.
well away from dampers.
Pitot Tube
Figure A
Figure B
Figure C
Pitot Tube and Gauge
Placement of the Pitot Tube
Push and turn with slotted
screwdriver. Damper
automatically locks when
pressure is released.
screwdriver. Damper
automatically locks when
pressure is released.
When connecting ductwork
to the collar, take note where
screws are located. Screws
should be located no further
than 1/2” from outside edge
of collar, so as not to impede
operation of the damper.
to the collar, take note where
screws are located. Screws
should be located no further
than 1/2” from outside edge
of collar, so as not to impede
operation of the damper.
1/2”
Insulated flexible
ducting
Balancing Collar Instructions
Figure D