Locate The Unit; Unit Duct Connections; Rig And Place Unit - Bryant 551B Series Installation, Start-Up And Service Instructions Manual

I. LOCATE THE UNIT
A. Clearance
Maintain clearance around and above unit to provide mini-
mum distance from combustible materials, proper airflow, and
service access. See Fig. 2 and 3.
Minimum clearance to combustibles (when not using curb) is
0 in. on vertical discharge units and 1 in. on horizontal dis-
charge units.
Minimum clearance to block walls or any other grounded sur-
face is 42 in. on all sides.
Minimum clearance of 42 in. should be provided between units
on side with control box. Between unit and ungrounded sur-
faces, control box side, clearance is 36 inches.
Minimum clearance around condenser coil is 12 in. one side
and 36 in. the other side (side getting greater clearance is
optional).
Overhead minimum clearance is 60 in.
Do not install unit in an indoor location. Do not locate unit
air inlets near exhaust vents or other sources of contami-
nated air.
Although unit is weatherproof, guard against water from higher
level runoff and overhangs.
Slab mounted units should be at least 4 in. above the highest
expected water, flood, and runoff levels. Do not use the unit if
it has been under water.
Fig. 3 — Service and Operational Clearances
B. Roof Curb Mount
Assemble and install accessory roof curb in accordance with
instructions shipped with curb. See Fig. 4. Install insulation,
cant strips, roofing felt, and counter flashing as shown. Duct-
work must be attached to curb. If electric or control power is
to be routed through the curb, attach the utility connection
plates to the roof curb in accordance with the accessory in-
stallation instructions. Accessory electric utility connection
plates must be installed before unit is in place on roof curb.
IMPORTANT: The gasketing of the unit to the roof curb is
critical for a watertight seal. Install gasket with the roof curb
as shown in Fig. 4. Improperly applied gasket can also result
in air leaks and poor unit performance.
Curb should be level. Unit leveling tolerances are shown in
Fig. 5. Correct leveling tolerance is necessary for unit drain
to function properly.
C. Slab Mount (Horizontal Units Only)
Provide a level concrete slab that extends a minimum of
6 in. beyond unit cabinet. Install a gravel apron in front of
condenser-coil air inlet to prevent grass and foliage from
obstructing airflow.
NOTE: Horizontal units may be installed on a roof curb, if
required.
II. UNIT DUCT CONNECTIONS
On vertical units, secure all ducts to roof curb and building
structure. Do not connect ductwork to unit. On horizontal units,
field-supplied duct flanges should be attached to horizontal
openings and all ductwork should be secured to flanges. In-
sulate and weatherproof all external ductwork, joints, and roof
openings with counter flashing and mastic in accordance with
applicable codes.
Ducts passing through an unconditioned space must be in-
sulated and covered with a vapor barrier.
If a plenum return is used on a vertical unit, the return should
be ducted through the roof deck to comply with applicable
fire codes.
A minimum clearance to combustibles is not required around
ductwork on vertical discharge units. On horizontal dis-
charge units, a minimum clearance of 1.0 in. is required
for the first 12 in. of ductwork. Cabinet return-air static
shall not exceed −0.35 in. wg with Varislide™ economizer,
−0.35 in. wg with PARABLADE economizer, or −0.45 in. wg
without economizer.
NOTE: Connection must be made to roof curb before unit is
set in place.
III. RIG AND PLACE UNIT
Inspect unit for transportation damage. File any claim with
transportation agency. Keep unit upright and do not drop.
Spreader bars are not required if top crating is left on unit.
Rollers may be used to move unit across a roof. Level by us-
ing unit frame as a reference. See Table 1 and Fig. 6 for ad-
ditional information. Operating weight is shown in Table 1
and Fig. 6.
Lifting holes are provided in base rails as shown in Fig. 6.
Refer to rigging instructions on unit.
IMPORTANT: If unit has forklift protection skids, be sure to
remove forklift protection skids from under unit before set-
ting unit in place.
CAUTION: All panels must be in place when
rigging.
A properly positioned unit will have the following clearances
between unit and roof curb:
and base rails on each side and front of unit; 1
ance between roof curb and rear of unit. See Fig. 4, Views
A-A and C-C.
After unit is in position, remove polyethylene shipping wrap-
per and top crating.
—3—
1 ⁄ -in. clearance between roof curb
4
⁄ -in. clear-
5
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