General Assist Technical Reference

J Series Outdoor Unit Operational Control

Outdoor unit input, output and control range reference
Reference for J Series outdoor unit operation control, sensors, protection inputs, external inputs and controlled outputs.
This reference summarises the outdoor unit input / output list used by the J Series control system. It identifies the principal sensors, protection devices, external control inputs, compressor and valve outputs, communication signals and LED indication.
Service personnel only: Electrical measurements and control-system checks must be carried out by suitably qualified personnel. Isolate power where required and observe the applicable electrical and refrigerant safety procedures.

1. Outdoor unit inputs

Temperature and current sensing

InputInput / output part or detailControl range / function
Discharge temperature sensor 1ThermistorMeasure range: -30 to 130°C
Heat exchanger liquid temperature sensor 1ThermistorMeasure range: -30 to 70°C
Heat exchanger temperature sensor (Middle)ThermistorMeasure range: -30 to 70°C
Suction gas temperature sensorThermistorMeasure range: -30 to 40°C
Outdoor temperature sensorThermistorMeasure range: -30 to 60°C
Operation current sensorCurrent transCurrent monitoring input
IPM over current sensorIPM with built-in sensorIPM over-current detection

Communication and setting inputs

InputDetailFunction
Serial signalTransmission signal from indoor unitIndoor-to-outdoor communication
DIP-SW inputDip-switch functionOutdoor unit operating / configuration settings

Pressure protection inputs

InputDeviceProtection point
Pressure SW 1 (Discharge)Pressure switchPressure ≥ 609 ±15 psi
(4.2 ±0.1 MPa)
Pressure SW 2 (Suction)Pressure switchPressure ≤ 29 ±7 psi
(0.2 ±0.05 MPa)
External input wiring: The source specifies dry-contact inputs. Where a twisted-pair cable is used, the specified conductor size is 22 AWG with a maximum wire length of 25 m.

External control inputs

InputFunctionContact type
External input 1External input / RC priorityDry contact
External input 2Setting of priority (Cooling / Heating)Dry contact

2. Outdoor unit outputs

OutputOutput part / detailControl range / supply
Compressor (DC inverter)Scroll compressor20 to 100 rps
Fan motor (Hi / Lo / OFF)Fan motorAC 208–240 V, 50/60 Hz
Expansion valveEEV coilCoil DC 12 V
4-way valve 1 (Cooling or Heating)Coil of 4-way valveCoil AC 208–240 V, 50/60 Hz, 10 W
Solenoid valve 1Hot gas bypassCoil AC 208–240 V, 50/60 Hz, 10 W
Solenoid valve 2Liquid injection bypassCoil AC 208–240 V, 50/60 Hz, 10 W

External output terminals

OutputStateElectrical output
External output terminal 1 (Operation)ON / OFFDC 0 / 12 V, maximum 100 mA
External output terminal (Abnormal)ON / OFFDC 0 / 12 V, maximum 100 mA
Twisted pair cable: 22 AWG, wire length ≤ 25 m

Communication and indication outputs

OutputDetail
Serial signal outputTransmission signal from outdoor unit
LED displayLED 1–6

3. Quick diagnostic reference

CheckReference value / function
Discharge thermistor-30 to 130°C measuring range
Heat exchanger thermistors-30 to 70°C measuring range
Suction gas thermistor-30 to 40°C measuring range
Outdoor thermistor-30 to 60°C measuring range
High-pressure protection≥ 609 ±15 psi (4.2 ±0.1 MPa)
Low-pressure protection≤ 29 ±7 psi (0.2 ±0.05 MPa)
Compressor speed20 to 100 rps
EEV coilDC 12 V
4-way / solenoid valve coilsAC 208–240 V, 50/60 Hz, 10 W
External outputsDC 0 / 12 V, maximum 100 mA
Service tip: When diagnosing an operational fault, first establish whether the control is receiving the expected sensor or protection input, then confirm the corresponding output command and electrical supply to the controlled component. This table provides the reference ranges and output specifications shown in the source material.
Technical reference based on J Series outdoor unit operation control information supplied to General Assist.