Lennox XC20-036-230-01 Installation And Service Procedure page 28

Table 5 continued.
WARNING - Electric Shock Hazard. Can cause injury or death. Unit must be grounded in accordance with national and
local codes. The 4 pins in P6 have the potential of transferring up to 250 volts to the unit cabinet ground.
Designator
P6 - Pin 1 Tx
Inverter
P6 - Pin 2
Common
P6 - Pin 3 Rx
P6 - Pin 4 Inv 5V
LIQ
LIQ
AMB
AMB
COIL
COIL
Pump Down
L
C
XC20
Outdoor Control Terminal Designations and Input /Outputs
Description
Transmit data to inverter, connects to
Rx of inverter.
Inverter common
NOTE - This is a signal reference point
and not an earth ground.
Receive data from the inverter.
Connects to Tx of inverter.
Inverter 5VDC volts.
Liquid line temperature sensor sup­
ply.
Liquid line temperature sensor return.
Outdoor ambient temperature sensor
supply.
Outdoor ambient temperature sensor
return.
Outdoor coil temperature sensor sup­
ply.
Outdoor coil temperature sensor re­
turn.
To initiate pump-down function, place jumper in
the ON position. (See PUMP-DOWN MODE
OPERATION on page 37.)
1. Place the jumper in the ON position to
activate pump-down mode.
2. Place the jumper in the OFF position to
deactivate pump-down mode.
NOTE -If the pump-down jumper is in the ON
position during power-up, it is ignored.
NOTE - The outdoor control stays in pump-down
mode for five minutes, after which the outdoor
control initiates a compressor
sequence.
Load-shedding input
Load-shedding input reference. Refer
to wiring of load-shedding terminals
located on page 47.
Input
Outdoor control
communication
transmit pin.
Inverter common.
Outdoor control
communication
receive pin.
Inverter 5VDC volts
N/A
N/A
N/A
N/A
N/A
N/A
shutdown
24VAC input to L en­
ergizes load shed­
ding feature.
N/A
28
Output
• Pin 1 to pin 2 should read 4.5 to 5.5
VDC when not communicating.
• Pin 3 to pin 2 should read 4.5 to 5.5
VDC when not communicating.
• Pin 4 to pin 2 should read 4.5 to 5.5
VDC.
NOTE - Communication signals switch off
and on rapidly. This may cause volt meter
readings to fluctuate.
Communication signals
between this 5V and common (Pin 2).
N/A
N/A
N/A
N/A
N/A
N/A
ON
OFF
PUMP
PUMP
DOWN
DOWN
N/A
N/A
Common
This is normal.
will switch
N/A
N/A
N/A
N/A
N/A
N/A
ON
OFF
N/A
24VAC
common