Service Manual -
HRG18xxS1P
508206-01
Issue 2140
Page 28 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
P6 - Pin 1
Tx
Transmit data to inverter, connects to Rx of inverter
Outdoor control
communication
transmit pin
– Pin 1 to pin 2 should read 4.5 to 5.55
VDC when not communicating
– Pin 3 to pin 2 should read 4.5 to 5.55
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. This is normal.
Communication signals will switch between
this 5V and common (Pin 2).
P6 - Pin2
Inverter
Common
Inverter common
NOTE – This is a signal reference point and not an earth
ground.
Inverter common
P6 - Pin 3
Rx
Receive data from the inverter
Connects to Tx of inverter
Outdoor control
communication
receive pin
P6 - Pin 4
Inv 5V
Inverter 5VDC volts
Inverter 5VDC volts
DIS
Discharge Line temperature sensor - not used (10K ohm
resistor installed)
N/A
N/A
N/A
DIS
Discharge Line temperature sensor - not used (10K ohm
resistor installed)
N/A
N/A
N/A
AMB
Outdoor ambient temperature sensor supply
N/A
N/A
N/A
AMB
Outdoor ambient temperature sensor return
N/A
N/A
N/A
COIL
Outdoor coil temperature sensor - not used (10K ohm
resistor installed)
N/A
N/A
N/A
COIL
Outdoor coil temperature sensor - not used (10K ohm
resistor installed)
N/A
N/A
N/A
CHRG MODE
Charge Mode function. Can be used when charging,
checking charge, pump down or checking unit operation.
Unit will run at 100% capacity.
Conventional 24VAC heat pump thermostat - Cooling
mode
1. Provide a Y1 compressor demand and a O Reversing
Valve signal to the HRG18
2. Install the Charge Mode jumper (after the Y1 demand)
3. A blower demand must be provided to the indoor unit
for 100% of the cooling air volume.
4. Remove the charge mode jumper to end the charge
mode
Conventional 24VAC Heat Pump Thermostat - Heating
Mode
1. Provide a Y1 compressor heating demand (without an
O demand)
2. Install the Charge Mode jumper (after the Y1 demand)
3. A blower demand must be provided to the indoor unit
for 100% of the heating air volume.
4. Remove the charge mode jumper to end the charge
mode.
NOTE - If the charge mode jumper is in the ON position
during power-up, it is ignored.
NOTE - If the charge mode is left in place, it will be
ignored after 60 minutes.
CHRG
Charge Mode
Disabled
Charge Mode
Enabled
MODE
CHRG
MODE
Suction Pressure Out
Pressure transducer Supply Voltage Pin 1 of 3
5 VDC
Suction Pressure In
Pressure transducer output voltage Pin 2 of 3
0.5-4.5 VDC
Suction Pressure GND Pressure transducer GND Pin 3 of 3
VDC Com
Liquid Pressure Out
Pressure transducer Supply Voltage Pin 1 of 3
5 VDC
Liquid Pressure In
Pressure transducer Supply Voltage Pin 2 of 3
0.5-4.5 VDC
Liquid Pressure GND
Pressure transducer GND Pin 3 of 3
VDC Com
SUCT1
Suction Line Temperature Sensor Supply - Pin 1 of 4
2.680k ohms to
327.3k ohms
Table 11. Outdoor Control Terminal Designations and Input /Outputs