2.2.3 S
I
IMPLIFIED
NSTALLATION
The central forced-air system must be synchronized with the unit since fresh air evacuation and distribution come from the
same section. The central forced-air system must operate to avoid fresh air to be directly drawn by the evacuation, which
would reduce signifi cantly fresh air supply to the building. See Section 3.3 for ducting.
Duct connection to the central forced-air system can be regulated by some codes and standards. It is your responsibility
to consider and comply with your local requirements to avoid any non-compliance.
Fresh air and exhaust air fl ow through the central forced-air system ducts,
which simplifi es the installation.
The use of bathroom fans and a range hood is suggested to exhaust stale
air.
S
:
TALE AIR EXHAUST DUCTWORK
Connect the stale air intake port of the unit to the central forced-air
system return duct at least 3 feet ahead of the fresh air distribution from
the unit.
F
:
RESH AIR DISTRIBUTION
Connect the fresh air distribution duct of the unit to the central forced-
air system return duct at least 10 feet away from the central forced-air
system (A+B)*.
* This 10-ft. distance applies only in areas where the outside temperature
falls below the freezing point (32°F).
NOTE: For this type of confi guration, the T-4 option must be
selected on the LCD screen when auto-balancing the unit.
(T-5)
A
:
LTERNATE INSTALLATION
Unit should be synchronized with central forced-air system operation
to avoid condensation and mold growth in central forced-air system
distribution ducting if cooling mode of central forced-air system is used.
This confi guration is not recommended with high velocity central
forced-air system. High pressures produced by these systems
could affect unit proper operation and generate errors.
NOTE: For this type of confi guration, the T-5 option must be
selected on the LCD screen when auto-balancing the unit.
(T-4)
CAUTION
CAUTION
!
WARNING
C
Stale air from
building
Fresh air from
outdoors
VH0167
Stale air from
building
Fresh air from
outdoors
VH0168
7
A
Fresh air to
building
B
Stale air to
outdoors
A+B=
MIN
C=3'
Fresh air to
building
Stale air to
outdoors
10'