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441 01 3700 00
Specifications are subject to change without notice.
20
Table 5 – 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 (12.7)
0.622(158)
175
120
97
82
73
3/4 (19.0)
0.824 (20.9)
360
250
200
170
151
1 ( 25.4)
1.049 (26.6)
680
465
375
320
285
1-1/4
(31.8)
1.380 (35.0)
1400
950
770
660
580
1-1/2
(38.1)
1.610 (40.9)
2100
1460
1180
990
900
* Cubic ft of 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:
Table 6 and 9.2 NFGC.
FIRE OR EXPLOSION HAZARD
A failure to follow this warning could result in personal
injury, death, and/or property damage.
If local codes allow the use of a flexible gas appliance
connector, always use a new listed connector. Do not use a
connector which has previously served another gas
appliance. Black iron pipe shall be installed at the furnace
gas control valve and extend a minimum of 2--in. (51 mm)
outside the furnace.
!
WARNING
FURNACE DAMAGE HAZARD
Failure to follow this caution may result in furnace damage.
Connect gas pipe to furnace using a backup wrench to
avoid damaging gas controls and burner misalignment.
CAUTION
!
An accessible manual equipment shutoff valve MUST be
installed external to furnace casing and within 6 ft. (1.8 M) of
furnace. A 1/8--in. (3 mm) NPT plugged tapping, accessible for
test gauge connection, MUST be installed immediately upstream
of gas supply connection to furnace and downstream of manual
equipment shutoff valve.
NOTE
:
The furnace gas control 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.
W.C.) stated on gas control valve. (See Fig. 42.)
Some installations require gas entry on right side of furnace (as
viewed in upflow). (See Fig. 21.)
Install a sediment trap in riser leading to furnace as shown in Fig.
22. Connect a capped nipple into lower end of tee. Capped nipple
should extend below level of furnace gas controls. Place a ground
joint union between furnace gas control valve and exterior
manual equipment gas shutoff valve.
A 1/8--in. (3 mm) NPT plugged tapping, accessible for test gauge
connection, MUST be installed immediately upstream of gas
supply connection to furnace and downstream of manual
equipment shutoff valve.
Piping should be pressure and leak tested in accordance with the
current addition of the 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.
2” (51mm)
Street Elbow
A08551
Fig. 21 -- Burner and Manifold
UNION
SEDIMENT
TRAP
MANUAL
SHUTOFF
VALVE
(REQUIRED)
GAS
SUPPLY
A02035
Fig. 22 -- Typical Gas Pipe Arrangement
ELECTRICAL CONNECTIONS
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow safety warnings could result in
dangerous operation, serious injury, death or property
damage.
Improper servicing could result in dangerous operation,
serious injury, death or property damage.
-- Before servicing, disconnect all electrical power to
furnace.
-- When servicing controls, label all wires prior to
disconnection. Reconnect wires correctly.
-- Verify proper operation after servicing.
!
WARNING