Step 3 - Field Fabricate Ductwork; Step 4 - Make Unit Duct Connections; Step 5 - Trap Condensate Drain - Bryant 551A Installation, Start-Up And Service Instructions Manual

III. STEP 3 — FIELD FABRICATE DUCTWORK
Secure all ducts to building structure. Use flexible duct con-
nectors between unit and ducts as required. Insulate and
weatherproof all external ductwork, joints, and roof openings
with counter flashing and mastic in accordance with applica-
ble codes.
Ducts passing through an unconditioned space must be insu-
lated and covered with a vapor barrier.
The 551A units with electric heat require a 1-in. clearance
for the first 24 in. of ductwork.
Outlet grilles must not lie directly below unit discharge.
NOTE: A 90-degree elbow must be provided in the ductwork
to comply with UL (Underwriters' Laboratories) codes for
use with electric heat.
WARNING: For vertical supply and return units, tools
or parts could drop into ductwork and cause an injury.
Install a 90 degree turn in the return ductwork between the
unit and the conditioned space. If a 90 degree elbow cannot
be installed, then a grille of sufficient strength and density
should be installed to prevent objects from falling into the
conditioned space. Due to electric heater, supply duct will
require 90 degree elbow.
NOTE: Do not drill in this area, as damage to basepan may result in
water leak.
Fig. 6 — Air Distribution — Thru-the-Bottom
(551A180 and 240 Shown)
NOTE: Do not drill in this area, as damage to basepan may result in
water leak.
Fig. 7 — Concentric Duct Air Distribution
(551A180 and 240 Shown)
IV. STEP 4 — MAKE UNIT DUCT CONNECTIONS
Unit is shipped for thru-the-bottom duct connections. Duct-
work openings are shown in Fig. 6. Field-fabricated concen-
tric ductwork may be connected as shown in Fig. 7 and 8.
Attach all ductwork to roof curb and roof curb basepans.
Refer to installation instructions shipped with accessory roof
curb for more information.
V. STEP 5 — TRAP CONDENSATE DRAIN
See Fig. 4, 5, and 9 for drain location. Plug is provided in
drain hole and must be removed when unit is operating. One
3
/ -in. half-coupling is provided inside unit evaporator sec-
4
tion for condensate drain connection. An 8
diameter nipple and a 2-in. x
coupled to standard
straight path down through holes in unit base rails (see
Fig. 10). A trap at least 4-in. deep must be used.
Shaded area indicates block-off panels.
NOTE: Dimension A, A' and B, B' are obtained from field-supplied ceil-
ing diffuser.
CAUTION:
Concentric ducts may only be installed on
units without electric heat. Personal injury or unit damage may
result.
Fig. 8 — Concentric Duct Details
INDOOR FAN MOTOR ACCESS
FILTER
ACCESS
Fig. 9 — Condensate Drain Details
— 7 —
1
/
2
3
/ -in. diameter pipe nipple are
4
3
/ -in. diameter elbows to provide a
4
3/4" FPT DRAIN 1-3/8"
CONNECTION DRAIN HOLE
(551A155 Shown)
3
in. x / -in.
4