Bryant 345MAV User Manual

Page 20

WARNING:

Gas valve ON and OFF switch MUST be

facing forward or tilted upward. (See Fig. 46.) Failure to
follow this warning could result in property damage or
death.

WARNING:

Never purge a gas line into a combustion

chamber. 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.

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.

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. 28.)

CAUTION:

If a flexible connector is required or al-

lowed by authority having jurisdiction, black iron pipe
shall be installed at furnace gas control valve and extend
a minimum of 2 in. outside furnace casing. Failure to
follow this caution will result in potential chaffing of
flexible gas connection.

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.

WARNING:

FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result
in serious injury, death or property damage.
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 fire
or explosion may result causing property damege, per-
sonal injury or loss of life.

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 gauge 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 gauge connection providing test pressure DOES NOT
exceed maximum 0.5 psig (14-in. wc) stated on gas valve. (See
Fig. 46.)

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 furnace gas valve and accessible
manual shutoff valve before test.

The gas supply pressure shall be within the maximum and
minimum inlet pressures marked on the rating plate with the
furnace burners ON and OFF.

ELECTRICAL CONNECTIONS

See Fig. 30 for field wiring diagram showing typical field 115-v
and 24-v wiring. Check all factory and field electrical connections
for tightness.

Field-supplied wiring shall conform with the limitations of 63°F
(35°C) rise.

Fig. 27—Removing Bottom Closure Panel

A93047

BOTTOM
CLOSURE
PANEL

FRONT FILLER
PANEL

TABLE 3—MAXIMUM CAPACITY OF PIPE

(CU FT PER HR)*

NOMINAL

IRON

PIPE
SIZE

(IN.)

INTERNAL

DIAMETER

(IN.)

LENGTH OF PIPE (FT)

1/2

0.622

175

120

3/4

0.824

360

250

200

170

151

1.049

680

465

375

320

285

1-1/4

1.380

1400

950

770

660

580

1-1/2

1.610

2100

1460

1180

990

900

* 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 12.2 NFPA
54-2002.

Fig. 28—Typical Gas Pipe Arrangement

A93324

UNION

SEDIMENT
TRAP

MANUAL
SHUTOFF
VALVE
(REQUIRED)

GAS
SUPPLY

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