Bryant Series B 345MAV User Manual

Page 19

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. 40.)
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
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.

ELECTRICAL CONNECTIONS

See Fig. 24 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.

Fig. 24—Heating and Cooling Application Wiring Diagram

A98209

115-V

FIELD-SUPPLIED

DISCONNECT

AUXILIARY
J-BOX

CONTROL

BOX

24-V

TERMINAL

BLOCK

THREE-WIRE

HEATING-

ONLY

FIVE

WIRE

NOTE 1

NOTE 2

FIELD-SUPPLIED
DISCONNECT

CONDENSING
UNIT

TWO
WIRE

FURNACE

GND

FIELD 24-V WIRING
FIELD 115-, 208/230-, 460-V WIRING
FACTORY 24-V WIRING
FACTORY 115-V WIRING

208/230- OR
460-V
THREE
PHASE

208/230-V
SINGLE
PHASE

WHT

BLK

WHT

BLK

NOTES:

Connect Y-terminal as shown for proper operation.
Some thermostats require a "C" terminal connection as shown.
If any of the original wire, as supplied, must be replaced, use
same type or equivalent wire.

GND

THERMOSTAT
TERMINALS

1.
2.
3.

TABLE 2—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 10-2 NFGC .

Fig. 23—Typical Gas Pipe Arrangement

A93324

UNION

SEDIMENT
TRAP

MANUAL
SHUTOFF
VALVE
(REQUIRED)

GAS
SUPPLY

—19—