Electrical Connections - Bryant 350MAV Installation, Start-Up, And Operating Instructions Manual

WARNING: 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.
TABLE 3—MAXIMUM CAPACITY OF PIPE*
NOMINAL
IRON INTERNAL
PIPE DIAMETER
SIZE (IN.)
(IN.)
1/2 0.622 175
3/4 0.824 360
1 1.049 680
1-1/4 1.380 1400
1-1/2 1.610 2100
* 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 10–2 NFGC.
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. 21.)
GAS
SUPPLY
MANUAL
SHUTOFF
VALVE
(REQUIRED)
SEDIMENT
TRAP
UNION
Fig. 21—Typical Gas Pipe Arrangement
CAUTION: If a flexible connector is required or al-
lowed by authority having jurisdiction, black iron pipe
shall be installed at gas valve and extend a minimum of
2 in. outside furnace casing.
An accessible manual shutoff valve MUST be installed upstream
of furnace gas controls 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 press 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. 44.)
Piping should be pressure tested in accordance with local and
national plumbing and gas codes before furnace is attached. In
Canada, refer to current edition of NSCNGPIC. If pressure
exceeds 0.5 psig (14-in. wc), gas supply pipe must be disconnected
LENGTH OF PIPE (FT)
10 20 30 40 50
120 97 82 73
250 200 170 151
465 375 320 285
950 770 660 580
1460 1180 990 900
A93324
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.
VIII. ELECTRICAL CONNECTIONS
See Fig. 22 for field wiring diagram showing typical field 115-v
and 24-v wiring. Check all factory and field electrical connections
for tightness.
WARNING: Blower access panel door switch opens
115-v power to control center. No component operation
can occur. Do not bypass or close switch with panel
removed. Failure to follow this warning could result in
personal injury or death.
CAUTION: Furnace control must be grounded for
proper operation or control will lock out. Control is
grounded through green wire routed to gas valve and
burner box screw.
A. 115–V Wiring
Before proceeding with electrical connections, make certain that
voltage, frequency, and phase correspond to that specified on unit
rating plate. Also, check to be sure that service provided by utility
is sufficient to handle load imposed by this equipment. Refer to
rating plate or Table 4 for equipment electrical specifications.
Make all electrical connections in accordance with National
Electrical Code (NEC) ANSI/NFPA 70-1999 and any local codes
or ordinances that might apply. For Canadian installations, all
electrical connections must be made in accordance with Canadian
Electrical Code CSA C22.1 or subauthorities having jurisdiction.
Use a separate, fused branch electrical circuit containing a properly
sized fuse or circuit breaker for this furnace. See Table 4 for wire
size and fuse specifications. A disconnecting means must be
located within sight from and readily accessible to furnace.
NOTE: Proper polarity must be maintained for 115-v wiring. If
polarity is incorrect, control center LED status indicator light will
flash rapidly and furnace will NOT operate.
ELECTRIC
DISCONNECT
SWITCH
CAUTION: Do not connect aluminum wire between
disconnect switch and furnace. Use only copper wire.
—18—
COPPER
WIRE ONLY
ALUMINUM
WIRE
A93033