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Electrical Connections
POWER SUPPLY
Do not apply power or close disconnect switch until
installation is complete. Refer to start-up directions.
Refer to unit nameplate for minimum circuit ampacity
and maximum fuse size.
1- 230,460,575 volt units are factory wired.
For 208V
supply
, disconnect the pink wire (230V) at all control
power transformer(s). 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 the top of K1 compressor contactor
or factory-installed disconnect or circuit breaker.
Secure power wiring with factory-installed wire
ties provided in control box. See unit wiring
diagram.
CONTROL WIRING
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 (1524 mm)
above the floor in an area with good air circulation at
average temperature. Avoid locating the room
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
IMPORTANT - Unless field thermostat wires are rated
for maximum unit voltage, they must be routed away
from line voltage wiring.
B-Control Wiring
1- Route thermostat cable or wires from subbase to
unit control box (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
front of the control section to secure thermostat cable.
Use18 AWG wire for all applications using remotely
installed electro-mechanical and electronic
thermostats.
2- Install thermostat assembly in accordance with
instructions provided with thermostat.
3- Connect thermostat wiring to TB1 terminal board on
the lower side of the controls hat section. Wire as
shown in figure 14 for electro-mechanical and
electronic thermostats. If using other temperature
control devices or energy management systems see
instructions and wiring diagram provided by
manufacturer.
FIGURE 14
24 VOLT FIELD WIRING WITH ELECTRONIC AND
ELECTRO-MECHANICAL THERMOSTATS
NOT ALL TERMINALS
ARE FOUND ON ALL
THERMOSTATS
Note - On electro-mechanical thermo
stats set anticipator at 0.1 amps.
Jumper terminals R and
OC when thermostat has
no night setback terminals
on units equipped with an
economizer.
A2 THERMOSTAT
TB1
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.
Unit Power-Up
A-General
1- Make sure that unit is installed in accordance with the
installation instructions and applicable codes.
2- Inspect all electrical wiring, both field and factory
installed, for loose connections. Tighten as required.
3- Check to ensure that refrigerant lines do not rub against
the cabinet or against other refrigerant lines.
4- Check voltage at main unit power connection.
Voltage must be within range listed on nameplate. If
not, consult power company and have voltage
condition corrected before starting unit.
5- Make sure filters are in place before start‐up.
6- Make sure there is no heating, cooling, or blower
demand from thermostat. Apply power to unit.