9
2. Remove flue hood from shipping location (inside the return
section of the blower compartment--see Fig. 9 & 10). Re-
move the return duct cover to locate the flue hood. Place flue
hood assembly over flue panel. Orient screw holes in flue
hood with holes in the flue panel.
3. Secure flue hood to flue panel by inserting a single screw on
the right side and the left side of the hood.
Step 8—Install Gas Piping
The gas supply pipe enters the unit through the access hole
provided. The gas connection to the unit is made to the 1/2--in. FPT
gas inlet on the gas valve.
Install a gas supply line that runs to the heating section. Refer to
Table 2 and the NFGC for gas pipe sizing. Do not use cast--iron pipe.
It is recommended that a black iron pipe is used. Check the local
utility for recommendations concerning existing lines. Size gas
supply piping for 0.5 in. wc maximum pressure drop. Never use
pipe smaller than the 1/2--in. FPT gas inlet on the unit gas valve.
For natural gas applications, the gas pressure at unit gas connection
must not be less than 4.0 in. wc or greater than 13 in. wc while the
unit is operating. For propane applications, the gas pressure must
not be less than 7.0 in. wc or greater than 13 in. wc at the unit
connection.
A 1/8--in. NPT plugged tapping, accessible for test gauge
connection, must be installed immediately upstream of the gas
supply connection to the gas valve.
When installing the gas supply line, observe local codes pertaining
to gas pipe installations. Refer to the NFGC ANSI Z223.1--2005
NFPA latest edition (in Canada, CAN/CGA B149.1).
NOTE
:In the state of Massachusetts:
1. Gas supply connections MUST be performed by a licensed
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.
In the absence of local building codes, adhere to the following
pertinent recommendations:
1. Avoid low spots in long runs of pipe. Grade all pipe 1/4 in.
for every 15 ft of length to prevent traps. Grade all horizontal
runs downward to risers. Use risers to connect to heating
section and to meter.
2. Protect all segments of piping system against physical and
thermal damage. Support all piping with appropriate straps,
hangers, etc. Use a minimum of one hanger every 6 ft (1.8
m). For pipe sizes larger than 1/2 in., follow
recommendations of national codes.
3. Apply joint compound (pipe dope) sparingly and only to
male threads of joint when making pipe connections. Use
only pipe dope that is resistant to action of liquefied
petroleum gases as specified by local and/or national codes.
Never use Teflon tape.
4. Install sediment trap in riser leading to heating section (See
Fig. 8). This drip leg functions as a trap for dirt and
condensate.
5. Install an accessible, external, manual main shutoff valve in
gas supply pipe within 6 ft (1.8 m)of heating section.
6. Install ground--joint union close to heating section between
unit manual shutoff and external manual main shut--off
valve.
7. Pressure test all gas piping in accordance with local and
national plumbing and gas codes before connecting piping
to unit.
OUT
TEE
NIPPLE
CAP
IN
C99020
Fig. 8 -- Sediment Trap
NOTE
: Pressure test the gas supply system after the gas supply
piping is connected to the gas valve. The supply piping must be
disconnected from the gas valve during the testing of the piping
systems when test pressure is in excess of 0.5 psig. Pressure test the
gas supply piping system at pressures equal to or less than 0.5 psig.
The unit heating section must be isolated from the gas piping system
by closing the external main manual shutoff valve and slightly
opening the ground--joint union.
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal injury,
death and/or property damage.
--Connect gas pipe to unit using a backup wrench to avoid
damaging gas controls.
--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.
--Use proper length of pipe to avoid stress on gas control
manifold.
--If a flexible connector is required or allowed by authority
having jurisdiction, black iron pipe shall be installed at furnace
gas valve and extend a minimum of 2 in. outside furnace casing.
--If codes allow a flexible connector, always use a new
connector. do not use a connector which has previously
serviced another gas appliance.
!
WARNING
8. Check for gas leaks at the field--installed and
factory--installed gas lines after all piping connections have
been completed. Use soap--and--water solution (or method
specified by local codes and/or regulations).
Step 9—Install Duct Connections
The unit has duct flanges on the supply-- and return--air openings on
the side and bottom of the unit. For downshot applications, the
ductwork connects to the roof curb (See Fig. 3 and 4 for connection
sizes and locations).
CONFIGURING UNITS FOR DOWNFLOW (VERTICAL)
DISCHARGE
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installing or servicing system, always turn off main
power to system. There may be more than one disconnect
switch.
!
WARNING
48E
S
