Lennox LHT/LDT024 Installation Instructions Manual page 12

FIELD WIRING WITH ELECTRONIC AND ELECTRO-MECHANICAL THERMOSTATS
24 V POWER
TO UNIT CONTROLLER
THERMOSTAT INPUTS
R
C
2
G
W1 S86
B
W2
A Y1
ALL OTHER
Y2
SIGNALS REMAIN CONNECTED
AS SHOWN ON THE RIGHT.
OCP
TO PROVIDE SUPERMARKET REHEAT SCHEME
USE S86 DEHUMIDISTAT AND K55.
FIELD WIRING IN ZONE SENSOR MODE
(Zone Sensor Mode)
UNIT CONTROLLER
SENSOR
24VAC
SENSOR
IAQ
R C
AI1
HUM
A2 SENSOR
FIGURE 16
Balance Point Setpoint
When outdoor air temperature is above setpoint (35_F
default), the unit will operate in heat pump mode. When
outdoor air temperature falls below setpoint, the unit will
operate in gas heat mode.
Note - Only stage one is used; stage 2 is not used.
Although the recommended balance point setpoint is
35_F, the setpoint can be adjusted. Weigh the comfort /
cost benefit when increasing the setpoint.
(Thermostat Mode)
TO R
2
7
TO G
K55−1
5
TO Y1
THERMOSTAT
OUTPUTS
TMP D01 D02
J298
J297A
1
R
2
C
B
3
G
4
W1
5
W2
2 6
Y1
7
Y2
8
OCP
C
9
10
FIGURE 15
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.
Page 12
P297
A55
W1
W2
LHT/LDT024, 036, 048, 060
10
11
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