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Specifications are subject to change without notice.
18
441 01 1422 00
1352420
Gray
5
2065
2005
1940
1875
1810
1740
1670
1600
1530
1470
Blue
4
1825
1760
1695
1630
1560
1490
1420
1350
1275
1205
Yellow
3
1760
1690
1625
1555
1485
1415
1345
1275
1200
1130
Orange
2
1620
1550
1480
1405
1335
1260
1195
1130
1065
995
Red
1
3
1325
1260
1185
1100
1025
955
885
805
735
670
1. A filter is required for each return-air inlet. Airflow performance included 3/4-in. (19 mm) washable filter media such as contained in factory-authorized
accessory filter rack. To determine airflow performance without this filter, assume an additional 0.1 In. W.C. available external static pressure.
2. Adjust the blower speed tabs as necessary for the proper air temperature rise for each installation.
3. Highlighted areas indicate airflow range is beyond the range allowed for heating.
THESE AIRFLOW RANGES MAY ONLY BE USED FOR COOLING.
4. -- Indicates unstable operating conditions.
Table 6 – Maximum Capacity of Pipe*
NOMINAL IRON
PIPE
INTERNAL
DIAMETER
LENGTH OF PIPE - FT. (M)
SIZE IN. (mm)
In. (mm)
10
20
30
40
50
1/2 (13)
0.622 (16)
175 (53)
120 (37)
97 (30)
82 (25)
73 (22)
3/4 (19)
0.824 (21)
360 (110)
250 (76)
200 (61)
170 (52)
151 (46)
1 (25)
1.049 (27)
680 (207)
465 (142)
375 (114)
320 (98)
285 (87)
1-1/4 (32)
1.380 (35)
1400 (427)
950 (290)
770 (235)
660 (201)
580 (177)
1-1/2 (38)
1.610 (41)
2100 (640)
1460 (445)
1180 (360)
990 (301)
900 (274)
* Cubic ft. of natural gas per hr for gas pressures of 0.5 psig (14-In. W.C.) or less and a pressure drop of 0.5-In. W.C. (based on a 0.60 specific gravity
gas). Ref: Chapter 6 current edition of ANSI Z223/NFPA 54.
Piping should be pressure and leak tested in accordance with
NFGC in the United States, local, and national plumbing and gas
codes before the furnace has been connected. After all
connections have been made, purge lines and check for leakage at
furnace prior to operating furnace.
If pressure exceeds 0.5 psig (14
−
In. W.C.), gas supply pipe must
be disconnected from furnace and capped before and during
supply pipe pressure test. If test pressure is equal to or less than
0.5 psig (14
−
In. W.C.), turn off electric shutoff switch located on
furnace gas control valve and accessible manual equipment
shutoff valve before and during supply pipe pressure test. After
all connections have been made, purge lines and check for
leakage at furnace prior to operating furnace.
The gas supply pressure shall be within the maximum and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON and OFF.
UNION
SEDIMENT
TRAP
MANUAL
SHUTOFF
VALVE
(REQUIRED)
GAS
SUPPLY
A02035
Fig. 18
−
Typical Gas Pipe Arrangement
A02075
Fig. 19
−
Upflow Return Air Configurations and Restrictions