Use the proper length of pipes to avoid stress on the gas
control manifold. Failure to follow this warning could result
in a gas leak, causing fire, explosion, personal injury, or
death.
Connect the gas pipe to the furnace using a backup wrench to
avoid damaging gas controls.
Never purge a line into a combustion chamber. Never use
matches, candles, flame, or other sources of ignition to check
for gas leakage. Use a soap-and-water solution to check for
gas leaks. Failure to follow this warning could result in fire,
explosion, personal injury, or death.
Joint compounds (pipe dope) should be applied sparingly and only
to the male threads of the joints. This pipe dope must be resistant
to the action of propane gas.
An accessible manual shutoff valve MUST be installed upstream
of the furnace gas controls and within 72 in. of the furnace. A
1/8-in. NPT plugged tapping, accessible for test gage connection,
MUST be installed immediately upstream of the gas supply
connection to the furnace and downstream of the manual shutoff
valve. Place a ground joint union between the gas control manifold
and the manual shutoff.
Install a sediment trap in the riser leading to the furnace. The trap
can be installed by connecting a tee to the riser leading from the
furnace. Connect a capped nipple into the lower end of the tee. The
capped nipple should extend below the level of the gas controls.
(See Fig. 13.)
Piping should be pressure tested in accordance with local and
national plumbing and gas codes before the furnace has been
attached. If the pressure exceeds 0.5 psig (14-in. wc), the gas
supply pipe must be disconnected from the furnace and capped
before the pressure test. If the test pressure is equal to or less than
0.5 psig (14-in. wc), turn off electric shutoff switch located on the
gas valve before the test. It is recommended that the ground joint
union be loosened before pressure testing.
After all connections have been made, purge the lines and check
for gas leakage with regulated gas supply pressure.
Step 10—Electrical Connections
115-V WIRING
Refer to the unit rating plate or Table 6 for equipment electrical
requirements. The control system requires an earth ground for
proper operation.
Do not connect aluminum wire between disconnect switch
and furnace. Use only copper wire.
Make all electrical connections in accordance with the current
edition of the National Electrical Code (NEC) ANSI/NFPA
70-1999, and any local codes or ordinances that might apply. For
Table 4—Filter Retainer (In.)
FURNACE CASING
WIDTH
FILTER SIZE AND
QUANTITY
D
14-3/16 (2) 14 X 20 X 1 14-3/8
17-1/2 (2) 14 X 20 X 1 13-3/8
21 (2) 16 X 20 X 1 11-5/8
24-1/2 (2) 16 X 20 X 1 10-1/4
Fig. 11—Horizontal Filter Arrangement
A82173
FIELD-SUPPLIED
FILTER RETAINERS
AIRFLOW
D
12″
4″
Fig. 12—Downflow Filter Arrangement
A88486
RETURN-AIR
PLENUM
AIRFLOW
ACCESS DOOR
INSTALLATION
POSITION
OF FILTERS
Table 5—Maximum Capacity of Gas Pipe *
NOMINAL IRON
PIPE SIZE
(IN.)
INTERNAL
DIAMETER
(IN.)
LENGTH OF PIPE (FT)
10 20 30 40 50
1/2 0.622 175 120 97 82 73
3/4 0.824 360 250 200 170 151
1 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
* 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 NFPA 54/ANSI Z223.1-1996.
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