035-17443-000 Rev. A (800)
10
Unitary Products Group
CRAWL SPACE INSTALLATION
The furnace can be hung from floor hoists or installed on suit-
able blocks or pad. Blocks or pad installations shall provide
adequate height to ensure the unit will not be subject to water
damage.
When suspending the furnace from rafters or floor joists
using rod, pipe or straps, refer to Figure 1 on page 6 and
Table 3 on page 6, for furnace weight and dimensions to
determine suitable means of suspension.
Angle supports should be located as shown in Figure 5 to
permit service of blower and burner compartments. All six
suspension points must be level to ensure proper door fit-up
and quiet furnace operation. Isolators should be used to mini-
mize noise being transferred to the structure. Furnace should
be securely fastened to the bottom angle iron bracket to pre-
vent movement and vibration.
GAS PIPING
NOTE:An accessible manual shutoff valve must be installed
upstream of the furnace gas controls and within 6 feet of the
furnace.
The furnace and its individual shutoff valve must be discon-
nected from the gas supply piping system during any pres-
sure testing of that system at test pressures in excess of 1/2
psig (3.48 kPa).
The furnace must be isolated from the gas supply piping sys-
tem by closing its individual external manual shutoff valve
during any pressure testing of the gas supply piping system
at test pressures equal to or less than 1/2 psig (3.48 kPa).
Gas piping may be connected from either side of the furnace.
Sizing and installation of the supply gas line should comply
with the local utility requirements.
The gas supply should be a separate line, installed in accor-
dance with the National Fuel Gas Code, ANSI Z223.1, or
CAN / CGA B149.1 or.2 Installation Codes - (latest editions).
Some utility companies, or local codes, require pipe sizes
larger than the minimum sizes listed. Use properly sized
wrought iron, approved flexible or steel pipe, to make gas
connections to the unit. Installation of a drop leg and ground
union is required (refer to Figure 6 )
FIGURE 4 : TYPICAL FURNACE INSTALLATION
USING SUSPENSION MATERIALS
FIGURE 5 : TYPICAL FURNACE INSTALLATION
USING SUSPENSION MATERIALS
An overpressure protection device, such as a
pressure regulator, which conforms to the National
Fuel Gas Code, ANSI Z223.1 (US) or CAN-B149.1
or .2 (Canada) and acts to limit the downstream
pressure to value that does not exceed 0.5 PSI
(14” w.c.), must be installed in the gas piping sys-
tem upstream of the furnace. Failure to do so may
result in a fire or explosion or cause damage to the
furnace or some of its components.
Never apply a pipe wrench to the body of the com-
bination automatic gas valve. A wrench must be
placed on the projection or wrench boss of the
valve when installing piping to it.
