Bryant 577C Installation Instructions Manual page 10

NOMINAL INTERNAL
IRON PIPE DIAMETER
10
SIZE (IN.) (IN.)
(3)
175
1/2 .622
(53)
360
3/4 .824
(110)
680
1 1.049
(207)
1400
1--- 1/4 1.380
(427)
2100
1--- 1/2 1.610
(640)
*Capacity of pipe in cu ft of gas per hr for gas pressure of 0.5 psig or less. Pressure drop of 0.5 ---in. wc (based on a 0.60 specific gravity gas). Refer to Table,
National Fire Protection Association NFPA 54.
{ This length includes an ordinary number of fittings.
1. Open all electrical disconnects before starting any service
work.
2. Remove horizontal (metal) duct covers to access vertical
(downflow) discharge duct knockouts in unit base.
3. Use a screwdriver and hammer to remove the panels in the
bottom of the unit base (See Fig. 10).
4. If unit ductwork is to be attached to vertical opening flanges
on the unit base (jackstand applications only), do so at this
time.
CAUTION
!
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in property
damage.
Collect ALL screws that were removed. Do not leave
screws on rooftop as permanent damage to the roof may
occur.
5. It is recommended that the base insulation around the
perimeter of the vertical return- -air opening be secured to
the base with aluminum tape. Applicable local codes may
require aluminum tape to prevent exposed fiberglass.
6. Cover both horizontal duct openings with the provided duct
covers. Ensure opening is air- - and watertight.
7. After completing unit conversion, perform all safety checks
and power up unit.
NOTE: The design and installation of the duct system must be in
accordance with the standards of the NFPA for installation of
nonresidence- -type air conditioning and ventilating systems, NFPA
90A or residence- -type, NFPA 90B; and/or local codes and
ordinances.
Table 2 – Maximum Gas Flow Capacity*
20 30 40 50
(6) (9) (12) (15)
120 97 82 73
(37) (30) (25) (22)
250 200 170 151
(76) (61) (52) (46)
465 375 320 285
(142) (114) (98) (87)
950 770 600 580
(290) (235) (183) (177)
1460 1180 990 900
(445) (360) (302) (274)
LENGTH OF PIPE FT (m)†
60 70 80 90
(18) (21) (24) (27)
66 61 57 53
(20) (19) (17) (16)
138 125 118 110
(42) (38) (36) (34)
260 240 220 205
(79) (73) (67) (62)
530 490 460 430
(162) (149) (140) (131)
810 750 690 650
(247) (229) (210) (198)
SUPPLY
DUCT
OPENING
Fig. 9 - - Supply and Return Duct Opening
DUCT COVERS REMOVED
Fig. 10 - - Vertical Duct Cover Removed
Adhere to the following criteria when selecting, sizing, and
installing the duct system:
1. Units are shipped for horizontal duct installation (by
removing duct covers).
2. Select and size ductwork, supply- -air registers, and
return- -air grilles according to American Society of Heating,
Refrigeration and Air Conditioning Engineers (ASHRAE)
recommendations.
3. Use flexible transition between rigid ductwork and unit to
prevent transmission of vibration. The transition may be
10
100 125 150 175
(30) (38) (46) (53)
50 44 40
—
(15) (13) (12)
103 93 84 77
(31) (28) (26) (23)
195 175 160 145
(59) (53) (49) (44)
400 360 325 300
(122) (110) (99) (91)
620 550 500 460
(189) (168) (152) (140)
RETURN
VENT HOOD
DUCT SHIPPING
OPENING
LOCATION
200
(61)
—
72
(22)
135
(41)
280
(85)
430
(131)
A05143
C99012