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6. Gas Supply and Piping
CARBON MONOXIDE POISONING, FIRE AND
EXPLOSION HAZARD.
Failure to follow these instructions could result in
death, personal injury and/or property damage.
Models designated for Natural Gas are to be used
with Natural Gas ONLY, unless properly converted to
use with LP gas.
!
WARNING
NOTE:
The rating plate is stamped with the model number, gas
type and gas input rating. In addition, models manufactured for
sale in Canada have orifice size information stamped on the rating
plate.
Gas Piping Requirements
1. Properly size gas pipe to handle combined appliance load
or run gas pipe directly from gas meter or LP gas regulator.
Refer to NFGC and ANSI Z223.1 for proper gas pipe size.
2. Install correct pipe size for run length and furnace rating.
3. Measure pipe length from gas meter or LP second stage
regulator.
NOTE:
In the state of Massachusetts:
1. Gas supply connectors MUST be performed by a licensed
plumber or gas fitter.
2. When flexible connectors are used, the maximum length
shall not exceed 36
²
(915 mm).
3. When lever handle type manual equipment shut off 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.
NOTE:
Refer to
Figure 35
or
Figure 36
for the general layout at
the furnace. The rules listed apply to natural and LP gas pipe
installations.
NOTE:
On the Dual Certified or Direct Vent models, install the gas
pipe grommet to the furnace side panel with the gas pipe entry. If
needed, remove the 2
²
hole plug and relocate to the open hole in
the furnace side panel.
FIRE OR EXPLOSION HAZARD
Failure to properly install metal gas connector could
result in death, personal injury and/or property
damage.
A flexible corrugated metal gas connector must be
properly installed, shall not extend through the side
of the furnace,and shall not be used inside the
furnace.
Black iron pipe shall be installed at the furnace gas
control valve and extend a minimum of 2
²²²²
outside
furnace casing.
!
WARNING
4. Use black iron or steel pipe and fittings or other pipe ap-
proved by local code.
5. Use ground joint unions and install a drip leg no less than 3
²
long to trap dirt and moisture before it can enter gas valve.
6. Use two pipe wrenches when making connections to pre-
vent gas valve from turning.
7. Install a manual shut--off valve external to furnace casing
and tighten all joints securely.
8. If local codes allow the use of flexible gas appliance connec-
tors, always use a new listed connector.
Do not use a connector which has previously serviced
another gas appliance.
Manual shut- off
valve
Use elbows and 3
²²²²
pipe nipple to connect
valve to piping when using right side gas
pipe entry.
* Union may be installed inside the cabinet when necessary because of clearances.
Figure 35
Typical Gas Piping for Upflow
Drip Leg and Union, Union* should be outside the
cabinet. Manual shut--off valve MUST be upstream of
dripleg, union, and furnace.
LP Low pressure switch.
Gas Pipe Grommet
(Single Pipe)
3
²²²²
pipe nipple
25--25--45
Alterative
installation
Содержание *9MPT050F12
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