Bryant LEGACY 580J*20M Series Installation Instructions Manual Download Page 16

Page: 16 / 56

Step 5 — Field Fabricate Ductwork

—

Cabinet return-

air static pressure (a negative condition) shall not exceed 0.5 in.

wg (87 Pa) with economizer or without economizer.

For vertical ducted applications, secure all ducts to roof curb

and building structure. Do not connect ductwork to unit.

Fabricate supply ductwork so that the cross sectional dimen-

sions are equal to or greater than the unit supply duct opening di-

mensions for the first 18 in. (458 mm) of duct length from the

unit basepan.

Insulate and weatherproof all external ductwork, joints, and

roof openings with counter flashing and mastic in accordance

with applicable codes.

Ducts passing through unconditioned spaces must be insulat-

ed 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 is not required around ductwork.

Step 6 — Rig and Place Unit —

Keep unit upright and do

not drop. Spreader bars are not required if top crating is left on

the unit. Rollers may be used to move unit across a roof. Level

by using unit frame as a reference. See Table 1 and Fig. 11 for

additional information.

Lifting holes are provided in base rails as shown in Fig. 11.

Refer to rigging instructions on the unit.

Before setting the unit onto the curb, recheck gasketing on

curb.

POSITIONING ON CURB —

Position unit on roof curb so

that the following clearances are maintained:

in. (6 mm) clear-

ance between the roof curb and the base rail inside the right and

left,

in. (12 mm) clearance between the roof curb and the base

rail inside the front and back. This will result in the distance be-

tween the roof curb and the base rail inside on the condenser end

of the unit being approximately equal to Details A and B in

Fig. 8-10.

Do not attempt to slide unit on curb after unit is set. Doing so

will result in damage to the roof curb seal.

Although unit is weatherproof, guard against water from

higher level runoff and overhangs.

Flue vent discharge must have a minimum horizontal clear-

ance of 48 in. (1220 mm) from electric and gas meters, gas regu-

lators, and gas relief equipment. Minimum distance between unit

and other electrically live parts is 48 in. (1220 mm).

Flue gas can deteriorate building materials. Orient unit such

that flue gas will not affect building materials. Locate mechani-

cal draft system flue assembly at least 48 in. (1220 mm) from an

adjacent building or combustible material.

After unit is in position, remove rigging skids and shipping

materials.

Fig. 11 — Rigging Details

CAUTION

Failure to follow this caution may result in damage to roof-

ing materials.
Membrane roofs can be cut by sharp sheet metal edges. Be

careful when placing any sheet metal parts on such roof.

CAUTION

Failure to follow this caution may result in equipment dam-

age.
All panels must be in place when rigging. Unit is not

designed for handling by fork truck when packaging is

removed.

NOTES:

1. Dimensions in ( ) are in inches.
2. Hook rigging shackles through holes in base rail, as shown in detail “A.” Holes in base rails are centered around the unit center of gravity.
3. Use wooden top skid, when rigging, to prevent rigging straps from damaging the unit.

UNIT

MAX WEIGHT

DIMENSIONS

in.

580J*17

2355

1068

127.8

3249

58.7

1491

52.3