11
2. INSTALLATION (
CONT
’
D
)
2.7
C
ONNECTING
THE
D
UCTS
TO
THE
U
NIT
NOTE: All units ports were created to be connected to ducts having a minimum of 5” diameter, but if need be, they can be connected
to bigger sized ducts by using an appropriate transition (e.g.: 5” diameter to 6” diameter transition).
Insulated flexible ducts:
All units have both Fresh air to building and Exhaust air to outdoors ports equipped with integrated balancing damper. Prior to
install the insulated flexible ducts on, ensure these both ports have their dampers set to wide open position (See Section 2.2)
CAUTION
Make sure the balancing dampers are set to wide open position before connecting the ducts to the ports. Also, the
ductwork connecting Fresh air to building and Exhaust air to outdoors ports with exterior hood(s) must be made of
insulated ducts, all way long.
Pull back the insulation to expose the flexible duct.
Attach the flexible duct to the port using tie wrap.
Pull the insulation over the joint and tuck in between the inner and outer rings of the double collar, then pull down the vapor barrier
(shaded part in illustrations below) over the insulation and tuck in between the inner and outer rings.
Apply duct tape to the joint (outer ring and vapor barrier) making an airtight seal. Avoid compressing the insulation when pulling
the tape tightly around the joint. Compressed insulation loses its R value and causes water dripping due to condensation on
the exterior surface of the duct.
Rigid ducts:
Use a small length (6” length) of flexible duct to connect the rigid duct to the ports in order to avoid vibration transmissions. Use
tie-wraps to perform connections, then seal with duct tape.
CAUTION
Do not use screws to connect the rigid ducts to the ports.
Use the following procedure for connecting the insulated flexible ducts to the port of the unit (
Exhaust air to outdoors
and
Fresh
air from outdoors
ports).
CAUTION
If ducts have to go through an unconditioned space (e.g.: attic), always use insulated ducts.
VJ0117
CAUTION
Make sure the vapor barrier on the insulated ducts does not tear during installation to avoid condensation within the
ducts.
