Specifications

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C. Location of Accessories
Where applicable, standard or optional accessories will
be placed inside the fan section of the unit for shipment
and must be removed and installed by the mechanical
or electrical contractor. Remotely located discharge or
inlet dampers must be equipped with an end switch and
interlocked to insure maximum design opening before
starting and running circuits may be energized.
D. Electrical Connections
Warning: Open all disconnect switches and
secure in that position before wiring unit.
Failure to do so may result in personal injury or
death from electrical shock.
Warning: Controls must be protected from
water. Do not allow water to drip on the
electrical controls.
Note: Before installing any wiring, check the unit
rating plate for power supply voltage, and
minimum amperage.
All wiring must comply with all applicable local, state,
provincial, and national electric codes. Since shipment
of unit may require disassembly after factory check and
test, reconnection of some electrical devices will be
required in the field. Connect electrical wires (supplied
in factory furnished conduit) to appropriate terminals.
All leads are tagged to facilitate field connections. See
wiring diagram provided with equipment. Complete all
wiring to any optional accessories as shown on unit bill
of material and electrical wiring diagram as required
before applying voltage to the unit.
Entry location for all field-installed and control wiring is
through the control panel.
If optional disconnect is not furnished with heater, the
field provided disconnect must be of the proper size and
voltage. Refer to unit nameplate for minimum circuit
ampacity and voltage. The disconnect must be installed
in accordance with Article 430 of the current edition of
ANSI/NFPA No. 70 National Electrical Code, and appli-
cable local codes; in Canada, to the Canadian Electrical
Code, Part 1, CSA Standard C22.1.
Check the supply voltage before energizing the unit.
The maximum voltage variation should not exceed
±10 %. Phase voltage unbalance must not exceed 2%.
NOTE: Should any original wire supplied with the
heater have to be replaced, it must be replaced
with wiring material having a temperature rating of
at least 105
o
C.
E. Venting
All venting installations must conform to Part 7, Venting
of Equipment in the current version of the National Fuel
Gas Code ANSI Z223.1, or applicable provisions of
local building codes.
All Indirect Fired Units must be vented. Each unit
must have an individual vent pipe and vent terminal.
Recommended vent pipe is 14 Gauge Series 400 Stain-
less Steel. Type “B” vent is not acceptable. The cus-
tomer must provide a rain cap or weather cap. DO NOT
support the weight of the stack on the induced draft fan
housing of the unit. Insulate single wall vent pipe ex-
posed to cold air or running through unheated areas.
The venting system for these heaters shall terminate at
least four feet below, four feet horizontally from, or one
foot above any door, window, or gravity air inlet into any
building. All vents must be able to maintain a minimum
of – 0.20’’ W.C. in high fire.
Through the wall vents for these heaters shall not termi-
nate over public walkways or over an area where con-
densate or vapor could create a nuisance or hazard or
could be detrimental to the operation of regulators, relief
valves, or other equipment.
The vent pipe diameter must be as shown in specifi-
cation chart on following page. An adaptor from
induced draft fan housing to vent pipe must be field
supplied.
The vent pipe should be fitted with a drip leg with a clean
out and a drain plug in the bottom. The vent pipe shall
be constructed so that any water that collects in the
stack will remain in the stack drip leg and not drain into
the induced draft fan housing. Be sure drip leg is made
so water will not fall on heater controls when drain plug
is removed.
Pitch horizontal pipes upward 1/4 inch per foot toward
outlet for condensate drainage. Support horizontal runs
as required to prevent sagging.
Vents should terminate that would not cause a down
draft to occur. This could affect the negative pressure
required in the heat exchanger. Do not install dampers
or other restrictive devices in the flue vent pipe.
The stack should not be installed in such a manner that
access to the components is obstructed. Guy wires may
be required to brace the stack above rooflines.
Outdoor units are supplied with a stack. The stack shall
have a minimum of at least 36” clearance to combus-
tible materials.