© 1995-2009 Energy Saving Products Ltd.
If elbows, tees, or Branch-Take Off’s are placed closer
than 18”
(457mm)
you may lose up to 30% of your airflow
as illustrated in
Fig. 05
.
Fig. 05 - Sigma velocity profile
Uniform
Velocity
Point
10% Loss
20% Loss
30% Loss
18”
(457mm)
Branch Tees
When branch tees are used, the plenum split is to be a
70/30 main/branch split
(Fig. 06)
.
Fig. 06 - Branch Tee, 70/30 split
Fan Coil
30% FLOW
6 Vents
70%
FLOW
14 Vents
EXAMPLE
20 VENTS
18” Min.
Fig. 07 - Bullhead Tee, 50/50 split
Fan Coil
EXAMPLE
20 VENTS
50% FLOW
(+/- 10%)
10 Vents
50% FLOW
(+/- 10%)
10 Vents
18” Min.
Bullhead Tees
Bullhead tees are to be maintained as close to a 50/50
split as possible, with a maximum 60/40 split
(Fig. 07)
. For
the best system performance, keep the number of elbows
and tees to a minimum.
After any connection is made, including the joints of
elbows and tees, foil duct tape or a duct sealant should be
used to eliminate any air leaks.
Fig. 08 - Seal all connections
Joist and Trusses
When running the plenum duct between joists in
the basement, sheet metal strapping should be used
(supplied by the installer, not the factory) to secure the
plenum in place
(Fig. 09)
.
Fig. 09 - Use metal strapping
When located in ceiling spaces, the duct may be laid
upon ceiling trusses. Run the duct work low so that it can
be covered with the house insulation
(Fig. 02)
.
Insulation Sleeve
Any time the duct will be run in an unconditioned space
(attic or crawl space) it must be insulated with a vapour
barrier. It’s also recommended to vapour barrier runs
that exceed 75% of the total allowable distance
(Module
SPC - Specifications and Sizing Pgs. 1, 2)
.
ENSURE
plenum
runs a
minimum
of 18”
(457mm)
before
any tees,
elbows and
take-offs.
Module DUC
Installing Plenum and Branch Duct (2/9)
Module DUC Installing Plenum and Branch Duct (2/9)
(457mm)
(457mm)
