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UNION
SEDIMENT
TRAP
MANUAL
SHUTOFF
VALVE
(REQUIRED)
GAS
SUPPLY
A93324
Fig. 27 -- Typical Gas Pipe Arrangement
COMBUSTION-AIR PIPE GROMMET
GAS LINE GROMMET
GAS LINE
COMBUSTION
-AIR PIPE
VENT PIPE
VENT PIPE GROMMET
UNUSED 1-3/4 -IN. (44 mm)
DIAMETER GAS
CONN. HOLE
GAS LINE ENTRY
HOLE FILLER PLUG
NOTE: PIPE GROMMETS AND ENTRY HOLE FILLER
PLUGS ARE INCLUDED IN FACTORY-SUPPLIED
LOOSE PARTS BAG
A05057
Fig. 28 -- Casing Pipe Grommets
Table 3 –
Maximum Capacity of Pipe*
NOMINAL
IRON
PIPE
SIZE
IN. (MM)
INTERNAL
DIA.
IN. (MM)
LENGTH OF PIPE --- FT (M)
10
(3.0)
20
(6.0)
30
(9.1)
40
(12.1)
50
(15.2)
1/2 (13)
0.622
(158)
175
120
97
82
73
3/4 (19)
0.824
(21)
360
250
200
170
151
1 (25)
1.049
(27)
680
465
375
320
285
1-1/4
(32)
1.380
(35)
1400
950
770
660
580
1-1/2
(38)
1.610
(41)
2100
1460
1180
990
900
* Cubic ft. of gas per hr for gas pressure of 0.5 psig (14--- in. wc) or less, and a pressure
drop of 0.5--- in. wc (based on a 0.60 specific gravity gas). Ref: Table 9--- 2 NFPA
54--- 2002.
NOTE
: The gas valve inlet pressure tap connection is suitable to
use as test gauge connection providing test pressure DOES NOT
exceed maximum 0.5 psig (14--in. wc) stated on gas valve. (See
Fig. 60.)
Piping should be pressure and leak tested in accordance with
NFGC in the United States or CAN/CSA--B149.1--05 in Canada,
local, and national plumbing and gas codes before the furnace has
been connected. If pressure exceeds 0.5 psig (14--in. wc), gas
supply pipe must be disconnected from furnace and capped before
pressure test.
If test pressure is equal to or less than 0.5 psig (14--in. wc), turn off
electric shutoff switch located on gas valve before test. It is
recommended that ground joint union be loosened before pressure
testing. After all connections have been made, purge lines and
check for leakage at furnace prior to placing it into service.
The gas supply pressure shall be within the maximum (13.6--in.
wc) and minimum (4.5--in. wc) inlet supply pressures marked on
the rating plate with the furnace burners ON at HI--HEAT and OFF.
58MV
C