Lennox iComfort SL18XC-01 Installer Setup Manual page 45

Figure 21. Wiring the Digital Ventilation Controller (iComfort Series Thermostat)
Thermostat Wire Termination in Communicating System
RSBus
Minimum wire size is 18
gauge
Outdoor Unit
BEST PRACTICES! Keep all communication wiring as far away from house electric­
al wiring and large electrical appliances as possible (15' [5m] recommended).
Communicating systems using the iComfort Wi‐Fi
thermostat wires between the thermostat and the furnace/air handler control
and four wires between the outdoor unit and the furnace/air handler control.
When a thermostat cable with more than four wires is used, the extra wires
must be properly connected to avoid electrical noise. The wires must not be
left disconnected.
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Note: iComfort Wi‐Fi thermostat does not require shielded cable wiring.
Indoor Unit
Controller
Single wire to
terminal C
Unused wires
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thermostat require four
Single wire to
terminal C
Unused wires
Maximum total length of all connections on the RSBus is limited to
1500 ft. (450 m). Max. length between components is 300 ft. (90 m).
Use wire nuts to bundle the unused wires at each end of the cable. A single
wire should then be connected to the indoor unit end of the wire bundle and
attached to the "C" terminals as shown in the diagram above.
This is not an issue in non-communicating systems.
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45 iComfort Wi‐Fi
iComfort Wi‐Fi
thermostat
7-Day Programmable Communicating Thermostat
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