Specifications

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F. Field Piping
All gas piping must be in accordance with the require-
ments outlined in the National Fuel Gas Code – ANSI
Z223.1. It is required that a ground union be installed
adjacent to the manifold for easy servicing. A drip leg
and/or filter should be provided upstream of the unit’s
inlet gas connection. An additional shut-off must be
located external of the unit’s enclosure where required
by local code. The location of this valve must comply
with all local codes. A 1/8 inch N.P.T. plugged tapping,
accessible for test gauge connection, must be installed
immediately upstream of the gas supply connection to
the unit.
WARNING: To avoid equipment damage or
possible personal injury, do not connect gas
piping to this unit until a supply line pressure/
leak test has been completed. Connecting the
unit before completing the pressure/leak test
may damage the unit gas valve and result in a
fire hazard.
DANGER: Never use an open flame to detect
gas leaks. Explosive conditions may exist
which would result in personal injury or death.
The gas line should be supported so that no strain is
placed on the unit. Pipe compounds, which are not
soluble to liquid petroleum gases, should be used on
threaded joints.
The appliance and its individual shutoff valve must be
disconnected from the gas supply piping system during
any pressure testing of that system at test pressures in
excess of
1
/
2
PSIG.
The appliance must be isolated from the gas supply
piping system by closing it’s individual manual shutoff
valve during any pressure testing of the gas supply
piping system at test pressure equal to or less than
1
/
2
PSIG.
Correctly sized piping must be run to the unit.
Please note that gas line pressure must be as
shown on specification plate when unit is
operating at full input. The high-pressure regulator
and relief valve should be, if possible, mounted at
least 5 to 10 feet upstream from the appliance
regulator on the unit (if applicable).
G. Field Wiring and Remote Control Installation
1. If the optional low temperature limit was not an inte-
gral part of the heater, the factory recommends that a
low temperature limit control be installed in areas where
freeze protection is needed in the event of burner shut
down.
2. Connect the power lines to the line side of the power
distribution block or optional main disconnect switch.
3.Field wiring is indicated on the wiring diagram,
typically dashed lines. Where field wiring of the control
circuit is required, take care to size the wires for a
maximum 10% voltage drop. The VA rating of the
transformer should be the maximum load.
4. Mount and wire remote control panel, thermostat
temperature sensors, and any other field-installed
controls as indicated on the unit control-wiring diagram.
5. Connect all wiring to the appropriate field wiring
terminal and any shielded or twisted wires as indicated
on the unit control-wiring diagram.
H. Locating Temperature Controls
The room or outdoor thermostats should be mounted
where they will not be subjected to direct impact of the
heated air or radiant heat from the sun. It is also recom-
mended that thermostats, especially those with mercury
bulb contacts, be mounted on a vibration free surface.
The sides of building columns, away from the heater or
interior walls, are usually the location best suited for
mounting thermostats.
Controls with outdoor bulbs require that the outdoor
bulb be shielded from direct radiation from the sun. Unit
mounted sensors are factory located and mounted.
I. Drains and Traps
Some furnaces may be supplied with condensation
removal pipe connections. Condensate from the heat
exchanger is acidic and may contain chemical com-
pounds requiring special drainage. The drain must be
installed in accordance with all plumbing codes. The
condensate is to be drained via PVC or steel pipe with
an indirect connection to the plumbing wastes. Where a
condensate neutralizer is used, an overflow shall be
provided such that condensate will be directed to the
drain in the event that the neutralizer becomes plugged.
Indoor units typically require a condensate trap to be
installed to prevent combustion gasses from entering
the space. Outdoor units may require installing a heat-
trace or special attention to drains to prevent freezing
and clogging of the drain line.
Since the condensate is drained by gravity, avoid long
runs of drain piping. If a long run of trapping cannot be
avoided or the piping has water flow restrictions such as
several elbows, and extra height to provide enough
hydrostatic head to overcome the frictional losses.
Always slope piping down a minimum of 1/8” per foot in
the direction of the flow.