Service Manual -
HRG18xxS1P
508206-01
Issue 2140
Page 27 of 83
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
Description
Input
Output
Common
O
O Reversing Valve Input (24VAC conventional Heat
Pump Thermostats only)
24VAC
Switched 24VAC
nominal
N/A
REV
Unused on HRG18 , for heat pump applications only
N/A
N/A
24VAC common
LPS
Low pressure switch
N/A
24VAC Nominal
N/A
LPS
Low pressure switch sensing connection
24VAC Nominal
N/A
N/A
HPS
High pressure switch
N/A
24VAC nominal
N/A
HPS
High pressure switch sensing connection
24VAC nominal
N/A
N/A
TP
Top cap thermostat switch (in series with the HPS)
N/A
24VAC nominal
N/A
TP
Top cap thermostat switch sensing connection
24VAC nominal
N/A
N/A
Cntctr
Control (inverter power) contactor switched output (in
series with the HPS and TC)
N/A
Switched 24VAC
nominal
N/A
Cntctr
Contactor common
N/A
24VAC common
FPWM
PWM fan output
N/A
10-97% duty cycle,
19-23 VDC peak
C
PWM fan common connection
N/A
N/A
Fan PWM
common
P10 (PSC Fan 1/4ʺ
QC)
1/4ʺ QC terminals - Switched output for PSC outdoor
fan control (not used on HRG18 heat pumps)
N/A
Switched 230VAC
Nominal
N/A
RAST Connector Terminal Designations
W
24VAC Output for defrost auxiliary heat output
N/A
24VAC nominal
N/A
L
24VAC input to initiate load shed
24VAC nominal
from load shed
N.O. contacts
(close to initiate
load shed)
N/A
N/A
Y2
Y2 second stage cooling input when a conventional
24VAC non-communicating thermostat is used. Must be
jumpered to Y1 if a single stage cooling thermostat is
used
24VAC nominal
from thermostat
N/A
N/A
Y1
Y1 first stage cooling input when a conventional 24VAC
non-communicating thermostat is used
24VAC nominal
from thermostat
N/A
N/A
O
O Reversing Valve Input (24VAC conventional Heat
Pump Thermostats only)
24VAC nominal
from thermostat
N/A
N/A
DS
Dehumidification input - not used
N/A
N/A
N/A
C
24VAC nominal power return
N/A
N/A
24VAC common
I-
Low data line
Data
Data
N/A
I+
High data line
Data
Data
N/A
R
24VAC nominal power input
24VAC nominal
board main power
input
N/A
N/A
DF
OEM test
N/A
N/A
N/A
TST
OEM test pin
24VAC nominal
N/A
N/A
Table 11. Outdoor Control Terminal Designations and Input /Outputs