Warning, Caution – Bryant Series E/F 310AAV User Manual

Page 19

accessories. All accessories MUST be connected to duct external
to furnace casing.

FIRE HAZARD
A failure to follow this warning could result in personal

injury, or death and/or property damage.
Never connect return--air ducts to the back of the

furnace. Follow instructions below.

WARNING

Return Air Connections
Downflow Furnaces
The return--air duct must be connected to return--air opening
(bottom inlet) as shown in Fig. 19. DO NOT cut into casing sides

(left or right). Side opening is permitted for only upflow and most
horizontal furnaces. (See Fig. 19.) Bypass humidifier connections

should be made at ductwork or coil casing sides exterior to
furnace.
Upflow and Horizontal Furnaces
The return--air duct must be connected to bottom, sides (left or
right), or a combination of bottom and side(s) of main furnace

casing as shown in Fig. 18 and 20. Bypass humidifier may be
attached into unused return air side of the furnace casing. (See

Fig. 18 and 20.)
Not all horizontal furnaces are approved for side return air
connections. (See Fig. 20.)
GAS PIPING

FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal

injury, death, and/or property damage.
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.

WARNING

FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal

injury, death, and/or property damage.
Use proper length of pipe to avoid stress on gas control

manifold and a gas leak.

WARNING

Gas piping must be installed in accordance with national and

local codes. Refer to current edition of NFGC.
Installations must be made in accordance with all authorities
having jurisdiction. If possible, the gas supply line should be a

separate line running directly from meter to furnace.
NOTE: In the state of Massachusetts:

1. Gas supply connections MUST be performed by a li-

censed plumber or gas fitter.

2. When flexible connectors are used, the maximum length

shall not exceed 36 inches (915 mm).

3. When lever handle type manual equipment shutoff valves

are used, they shall be T--handle valves.

4. The use of copper tubing for gas piping is NOT approved

by the state of Massachusetts.

Refer to Table 6 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. (1.8 M) Joint compound (pipe dope) should be applied

sparingly and only to male threads of joints. Pipe dope must be
resistant to the action of propane gas.

Table 6—Maximum Capacity of Pipe

NOMINAL

IRON PIPE

SIZE

IN. (MM)

INTERNAL

DIA.

IN. (MM)

LENGTH OF PIPE --- FT (M)

(3.0)

(6.0)

(9.1)

(12.1)

(15.2)

1/2 (12.7)

0.622

(158)

175

120

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 natural 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 ANSI Z223---2009/NFPA 54---2009.

FIRE OR EXPLOSION HAZARD
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 OVERHEAT HAZARD
Failure to follow this caution may result in unit component

damage.
Connect gas pipe to gas valve 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 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.

310AA