NorAire NC-FE series, Installation & Operating Instructions Manual

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05/16/2014 16 NI216
Outdoor temperature sensor (OT) – extend sensor to an outdoor location properly
sampling the outdoor temperature. Select a location away from direct sunlight and
where the sensor will not pick up false temperature from the heat pump outdoor unit,
refrigerant line sets, dryer vent, reflection off of steel siding, etc. Do not install the
sensor in any type of enclosure, as this will falsely trap and pick up radiant sun
temperature. Mount the sensor horizontally on the structure using the screws provided.
Other sensor related comments – if additional cable length is required, you must use the following rules for
extending the cable.
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Use unshielded (low capacitance, preferred twisted) 3 or 4-wire low voltage cable.
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50 feet (15 meters) is maximum (total).
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Do not, under any circumstances, use leftover wires within the normal thermostat cable.
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Route the sensor cable making sure you do not crimp, cut, staple, or damage the cable in any way.
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Keep sensor cables at least 12” (30.5cm) away from any line voltage wiring, romex, etc.
For easy sensor cable disconnect and reconnect, the WarmFlo board has a plug-in 4-place terminal block.
Before disconnecting, you will notice two red wires are under the red screw and two white wires is under the
COM screw. The black wire represents the data information from each sensor and must be connected to the
appropriate OT or ST screw.
The sensor has polarity, is sensitive to incorrect voltage, and must be protected from static voltage. Do not cross
connect or inadvertently short out sensor wires with power on. Permanent sensor damage may result.
Utility interrupt – this is marked “blue and blue/white”, leave jumper intact unless PC download setup is for
HP, boiler, or all. In this case remove blue jumper wire and connect the two screw terminals to a utility device
with closed = off-peak.
Note: The PC setup “utility interrupt” determines the action from this remote time clock or utility
device. If this setup is set as “none” any connection associated with these two terminal screw points
have no effect (see Field Setup section).
More than one controller within the overall system: Depending upon the configuration it is possible
to have other control boards requiring interrupt. Example, if the Electro Buffer Tank Controller is
connected (next section), the blue wire jumper remains on this NorAire board. Also, if the buffer tank
has a backup Electro-Boiler (for whatever reason there isn’t one within the NorAire cabinet) operating
as mode C, the external Electro-Boiler must have its own utility interrupt connection if it is to be
controlled. The mode C application assumes an external gas boiler.
Backup – only relates to operating mode C. The two tabs (T8 and T9) provide an isolated contact to the backup
or auxiliary boiler.