94
IM 738-2
Unit Options:
DesignFlow™ Outdoor Air Damper Option
Figure 94. Tape fulcrum alignment plate to vane
9
Locate and install the fulcrum used in the leveling
procedure as follows (see Figure 94):
a
Wipe the bottom of the louver door where the fulcrum
will be located so that the duct tape will stick to it.
b
Pre-apply duct tape to the top surface of the bottom
portion of the fulcrum, extending it about one inch
beyond the edges on three sides.
c
With the alignment plate taped to the vane and the vane
in the zero airflow position, locate the fulcrum parallel
to and against the alignment plate.
Note:
The zero airflow position is when the vane is
swung away from the back wall and gently resting
against its stop.
d
Once the fulcrum is in position, press the duct tape
extensions down to hold the fulcrum in place.
e
Remove the alignment plate after installing the fulcrum.
10
Close and latch the louvered intake door.
11
Remove the cover from the access opening in the bottom
blade of the outdoor air intake louver (see Figure 97
.
12
Verify that the unit fans are off and that the outdoor air
dampers are closed. If there is a wind, cover the outdoor air
louvers with poly film, cardboard, or other suitable material
to prevent adverse readings due to wind.
13
Rest the leveling weight assembly on the fulcrum, as shown
in Figure 95, so that:
a
Its bottom two thumbscrews rest on the top edge of the
fulcrum.
b
Its top thumbscrew rests against the vertical alignment
mark on the vane.
Note:
The alignment mark is located 0.50 inch in from
the bend on the outer edge of the vane. It
intersects with a hole located one inch up from
the bottom outer edge of the vane.
Figure 95. Place leveling weight on fulcrum
14
Set up the leveling test as follows:
a
While holding the weight so it stays on the fulcrum,
manually rotate the vane to the wide-open position,
manually return it to the zero CFM position, and gently
release the vane.
b
Locate the leveling weight assembly so its contact point
is against the vertical mark on the vane.
c
While the weight assembly teeters on the fulcrum,
gently rap the base frame to slightly vibrate the
assembly and encourage the vane to seek its equilibrium
point.
15
Read the current
LH Lvl Pos
= (or
RH Lvl Pos
=) parameter
in the DesignFlow Setup menu on the keypad/display.
These parameters vary from 20% to 80% depending on the
position of the DesignFlow vane
16
If the value indicated by the
LH Lvl Pos=
(
or RH Lvl Pos=
)
parameter is not within the range of
22.56% to 23.02%
(22.79% is ideal)
, adjust the level of the DesignFlow unit
using the procedure described in “Making Level
Adjustments” below.
17
When the
LH Lvl Pos
= (or
RH Lvl Pos
=) value is in range,
remove the fulcrum and leveling weight assembly and
replace the access opening cover in the louvered door.
Vane
Duct tape
This edge flush
with this side of vane
These edges flush
with bottom of vane
Fulcrum alignment plate
Fulcrum
Duct tape