Lennox DAVE SIGNATURE SL280DFV Installation Instructions Manual page 21

6 - Electrically ground the unit according to local codes
or, in the absence of local codes, according to the
current National Electric Code (ANSI/NFPA No. 70).
A green ground wire is provided in the field make-up
box.
NOTE - The SL280DFV furnace contains electronic
components that are polarity sensitive. Make sure that
the furnace is wired correctly and is properly grounded.
7 - One line voltage "ACC" 1/4" spade terminal is
provided on the furnace integrated control. Any
electronic air cleaner or other accessory rated
up to one amp can be connected to this terminal
with the neutral leg of the circuit being connected
to the one of the provided neutral terminals. See
FIGURE 23for control configuration. This terminal
is energized when the indoor blower is operating.
8 - An unpowered, normally open (dry) set of contacts
with a 1/4" spade terminal "HUM" are provided for
humidifier connections and may be connected to
24V or 120V. Any humidifier rated up to one amp
can be connected to these terminals. In 120V
humidifier applications the neutral leg of the circuit
can be connected to one of the provided neutral
terminals. This terminal is energized in the heating
mode.
9 - Install the room thermostat according to the
instructions provided with the thermostat. See
TABLE 10 for field wiring connections in varying
applications. If the furnace is being matched with
a heat pump, refer to the instruction packaged with
the dual fuel thermostat.
Thermostat Selection
CAUTION
Field wiring for both
communicating applications is illustrated in diagrams,
which begin on Page 22.
Non-Communicating
In non-communicating applications the SL280DFV is
designed to operate in a SINGLE-STAGE mode or
TWOSTAGE mode using a conventional thermostat.
For optimal performance in non-communicating applica-
tions, Lennox recommends use of a ComfortSense
high quality electronic digital thermostat or any other with
adjustable settings for 1st stage / 2nd stage on / off differ-
entials and adjustable stage timers.
communicating and non-
7000
®
Lennox recommends the following two-stage thermostat
settings:
First heat stage differential set to 1/2 to 1 degree F; sec-
ond heat stage differential set to 1/2 or 1 degree F; second
heat stage upstage timer disabled, or set to maximum (1
hr minimum).
Communicating
In communicating applications a communicating thermo-
stat must be used. Refer to the instructions provided with
the thermostat for installation, set-up and operation. In
communicating system all unused thermostat wire in the
wire bundle needs to be terminated inside and out. The
extra wires can terminate on the 'C" terminal of the com-
munication terminal strip. (RSBus). Using an additiona
wire come off "C" terminal and wire nut all the extra wires
together. Termination on the outdoor control must match
the indoor control.
Indoor Blower Speeds
Non-Communicating
1 - When the thermostat is set to "FAN ON," the indoor
blower will run continuously at a field selectable
percentage of the second-stage cooling speed
when there is no cooling or heating demand. The
factory default setting is 38% of cool speed.
2 - When the SL280DFV is running in the heating
mode, the indoor blower will run on the heating
speed designated by the positions of DIP switches
11, 12 and 13. First stage heating will run at 91%
heat speed.
3 - When there is a cooling demand, the indoor blower
will run on the cooling speed designated by the
positions of DIP switches 5 and 6. First stage
cooling will run at 70% cool speed.
Communicating
NOTE - When the SL280DFV is used with a communicat-
ing thermostat, proper indoor blower speed selections are
made by the thermostat.
1 - When the thermostat is set to "FAN ON," the indoor
blower will run at setting determined during system
configuration. See TABLE 25 on page 56 for
allowable circulation speeds.
2 - When there is a heating demand the fan will run on
heating speeds for firing rate.
3 - When there is a cooling demand, the fan will run on
the first stage and second stage cooling speed set
using the thermostat in the installer setup mode.
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