Electrical Connections - Lennox LCH Series Installation Instructions Manual

Electrical Connections

POWER SUPPLY
Do not apply power or close disconnect switch until
installation is complete. Refer to start-up directions.
Refer closely to unit wiring diagram.
Refer to unit nameplate for minimum circuit ampacity
and maximum fuse size.
1- Units are factory-wired for 230,460,575 volt supply.
For 208V supply, remove the insulated terminal cover
from the 208V terminal on the control transformer.
Move the wire from the transformer 240V terminal to
the 208V terminal. Place the insulated terminal cover
on the unused 240V terminal.
2- Route power through the bottom power entry area
and connect to L1, L2, and L3 on the top of K1 in
control area above compressor. Secure power
wiring with factory-installed wire ties provided in
control box. Route power to TB2 on units equipped
with electric heat. Route power to S48 or CB10 If
unit is equipped with the optional disconnect
switch or circuit breaker. See unit wiring diagram.
CONTROL WIRING
CAUTION
Electrostatic discharge can affect electronic com­
ponents. Take precautions during unit installation
and service to protect the electronic controls. Pre­
cautions will help to avoid control exposure to elec­
trostatic discharge by putting the unit, the control
and the technician at the same electrostatic poten­
tial. Neutralize electrostatic charge by touching
hands and all tools on an unpainted unit surface,
such as the gas valve or blower deck, before per­
forming any service procedure.
A-Thermostat Location
Room thermostat mounts vertically on a standard 2" X 4"
handy box or on any non-conductive flat surface.
Locate thermostat approximately 5 feet (1524mm)
above the floor in an area with good air circulation at
average temperature.
thermostat where it might be affected by:
-drafts or dead spots behind doors and in corners
-hot or cold air from ducts
-radiant heat from sun or appliances
-concealed pipes and chimneys
LGH/LCH036, 048, 060, 072, 074
Avoid locating the room
B-Control Wiring
The Unit Controller will operate the unit from a
thermostat or zone sensor based on the System Mode.
The default System Mode is the thermostat mode. Refer
to the Unit Controller Installation and Setup Guide to
change the System Mode. Use the menu navigation
arrows and select button; see Settings - Install.
Thermostat Mode
1- Route thermostat cable or wires from subbase to
control area above compressor (refer to unit
dimensions to locate bottom and side power entry).
IMPORTANT - Unless field thermostat wires are rated
for maximum unit voltage, they must be routed away
from line voltage wiring. Use wire ties located near the
lower left corner of the controls mounting panel to
secure thermostat cable.
Use18 AWG wire for all applications using remotely
installed electro-mechanical
thermostats.
2- Install thermostat assembly in accordance with
instructions provided with thermostat.
3- Connect thermostat wiring to Unit Controller on the
lower side of the controls hat section.
4- Wire as shown in figure 14 for electro-mechanical
and electronic
temperature control devices or energy management
systems see instructions and wiring diagram
provided by manufacturer.
IMPORTANT-Terminal connections at the wall plate or
subbase must be made securely. Loose control wire
connections may allow unit to operate but not with proper
response to room demand.
Zone Sensor Mode
The Unit Controller will operate heating and cooling
based on the Unit Controller internal setpoints and the
temperature from the A2 zone sensor. An optional
Network Control Panel (NCP) can also be used to provide
setpoints. A thermostat or return air sensor can be used
as a back-up mode. Make zone sensor wiring
connections as shown in figure 15.
Page 11
and electronic
thermostats. If using other