Carrier 58MVP Installation, Start-Up, And Operating Instructions Manual page 19

FRONT FILLER
PANEL
Fig. 26—Removing Bottom Closure Panel
made in accordance with NSCNGPIC and all authorities having
jurisdiction. Gas supply line should be a separate line running
directly from meter to furnace, if possible. Refer to Table 3 for
recommended gas pipe sizing. Risers must be used to connect to
furnace and to meter. Support all gas piping with appropriate
straps, hangers, etc. Use a minimum of 1 hanger every 6 ft. Joint
compound (pipe dope) should be applied sparingly and only to
male threads of joints. Pipe dope must be resistant to propane gas.
Table 3—Maximum Capacity of Pipe*
NOMINAL
IRON INTERNAL
PIPE DIAMETER
SIZE (IN.)
(IN.)
1/2 0.622
3/4 0.824
1 1.049
1-1/4 1.380
1-1/2 1.610
* Cubic ft of gas per hr for gas pressures 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.
Connect gas pipe to furnace using a backup wrench to avoid
damaging gas controls.
Gas valve shutoff switch MUST be facing forward or tilted
upward. Failure to follow this warning could result in
property damage or death.
→
Never purge a gas line into a combustion chamber. Never test
for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection of
leaks to check all connections. A failure to follow this
warning could result in fire, explosion, personal injury, or
death.
BOTTOM
CLOSURE
PANEL
A93047
LENGTH OF PIPE (FT)
10 20 30 40
175 120 97 82
360 250 200 170
680 465 375 320
1400 950 770 660
2100 1460 1180 990
Use proper length of pipe to avoid stress on gas control
manifold. Failure to follow this warning could result in a gas
leak resulting in fire, explosion, personal injury, or death.
Install a sediment trap in riser leading to furnace. Trap can be
installed by connecting a tee to riser leading to furnace so
straight-through section of tee is vertical. Then connect a capped
nipple into lower end of tee. Capped nipple should extend below
level of gas controls. Place a ground joint union between gas
control manifold and manual gas shutoff valve. (See Fig. 27.)
GAS
SUPPLY
MANUAL
SHUTOFF
VALVE
(REQUIRED)
SEDIMENT
TRAP
Fig. 27—Typical Gas Pipe Arrangement
50
73
If a flexible connector is required or allowed by authority
151
having jurisdiction, black iron pipe shall be installed at
285
furnace gas control valve and extend a minimum of 2 in.
580
outside furnace casing.
900
An accessible manual shutoff valve MUST be installed external to
furnace casing and within 6 ft of furnace. A 1/8-in. NPT plugged
tapping, accessible for test gage connection, MUST be installed
immediately upstream of gas supply connection to furnace and
downstream of manual shutoff valve.
NOTE: The gas valve inlet pressure tap connection is suitable to
use as test gage connection providing test pressure DOES NOT
exceed maximum 0.5 psig (14-in. wc) stated on gas valve. (See
Fig. 62.)
→
Piping should be pressure and leak tested in accordance with
NFGC in the United States or NSCNGPIC 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 and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON at HI-HEAT and OFF.
19
UNION
A93324