Unit Power-Up; Blower Operation And Adjustments - Lennox KHC092 Installation Instructions Manual

3- Connect thermostat wiring to TB1 terminal board on
the lower side of the controls hat section. Wire as
shown in figure 9 for electro-mechanical and
electronic thermostats. If using other temperature
control devices or energy management systems see
instructions and wiring diagram provided by
manufacturer.
4- Verify the unit configuration DIP switch settings
match the nameplate
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.
24 VOLT FIELD WIRING WITH ELECTRONIC AND
ELECTRO-MECHANICAL THERMOSTATS
IMPORTANT - Remove jumper between terminals R
and OC when thermostat has a night setback mode.
If reheat operation is desired during night setback,
move dehumidistat wire from OC to R.
R C G
0C DH Y1 Y2 Y3
A2 THERMOSTAT
NOT ALL TERMINALS
ARE FOUND ON ALL
THERMOSTATS
FIGURE 9

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.
TB1
W W2
A20
Note - On electro-me­
chanical thermostats set
anticipator at 0.1 amps.
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.

Blower Operation and Adjustments

A-Three Phase Scroll Compressor Voltage Phasing
Three phase scroll compressors must be phased
sequentially to ensure correct compressor and blower
rotation and operation. Compressor and blower are wired
in phase at the factory. Power wires are color-coded as
follows: line 1-red, line 2-yellow, line 3-blue.
1- Observe suction and discharge pressures and
blower rotation on unit start-up.
If pressure differential is not observed or blower rotation is
not correct:
2- Suction pressure must drop, discharge pressure
must rise, and blower rotation must match rotation
marking.
3- Disconnect all remote electrical power supplies.
4- Reverse any two field-installed wires connected to
the line side of TB13, TB2, or F4. Do not reverse wires
at blower contactor or compressors.
5- Make sure the connections are tight.
Discharge and suction pressures should operate at
their normal start‐up ranges.
Belt-Driven Supply Air Inverter Units - Units are equipped
with a phase monitor located in the control compartment. The
phase monitor will detect the phasing of incoming power. If
the incoming power is out of phase or if any of the three
phases are lost, the indicating LED on the phase monitor will
turn red and the unit will not start. In normal operation with
correct incoming power phasing, the LED will be green.
B-Blower Operation
Initiate blower demand at thermostat according to
instructions provided with thermostat. Unit will cycle on
thermostat demand. The following steps apply to
applications using a typical electro-mechanical thermostat.
1- Blower operation is manually set at the thermostat
subbase fan switch. With fan switch in ON position,
blowers will operate continuously.
2- With fan switch in AUTO position, the blowers will
cycle with demand. Blowers and entire unit will be off
when system switch is in OFF position.
C-Blower Access
The blower assembly is secured to a sliding frame which
allows the blower motor to be pulled out of the unit. See
figure 10.
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