General Assist Technical Reference
VII Outdoor Unit Input and Output List
Sensors, outputs, communications, external I/O and LED indication reference
This reference summarises the outdoor unit input and output points shown in the service information, including sensor ranges, pressure-switch values, controlled loads, communication paths and external terminals.
Service safety: Electrical measurements and testing must only be carried out by appropriately qualified personnel. Isolate power before accessing wiring or components unless live testing is specifically required by the applicable service procedure.
1. Outdoor unit inputs
| Input | Type | Control / measurement range |
|---|---|---|
| Discharge pressure sensor | Pressure sensor | 0.0 to 5.0 MPa |
| Suction pressure sensor | Pressure sensor | 0.0 to 1.7 MPa |
| Discharge temperature sensor 1 | Thermistor | 10 to 130°C |
| Discharge temperature sensor 2 | Thermistor | 10 to 130°C |
| Outdoor temperature sensor | Thermistor | -25 to 58°C |
| Suction temperature sensor | Thermistor | -35 to 70°C |
| Heat exchanger temperature sensor | Thermistor | -35 to 70°C |
| Liquid temperature sensor 1 | Thermistor | -35 to 70°C |
| Liquid temperature sensor 2 | Thermistor | -35 to 70°C |
| Sub-cool heat exchanger inlet sensor | Thermistor | -35 to 70°C |
| Sub-cool heat exchanger outlet sensor | Thermistor | -35 to 70°C |
| Compressor temperature sensor 1 | Thermistor | 10 to 130°C |
| Compressor temperature sensor 2 | Thermistor | 10 to 130°C |
| Operation current sensor | Current transformer | Not specified in source table |
| Pressure switch 1 (inverter compressor) | Pressure switch | Open 4.2 MPa / Short 3.2 MPa |
| Pressure switch 2 (constant speed compressor) | Pressure switch | Open 4.2 MPa / Short 3.2 MPa |
| Rotary SW / DIP-SW / Push SW | Address and function setting | Refer to applicable setup procedure |
Pressure switch quick reference: Both pressure switches are shown as opening at 4.2 MPa and returning to the short/normal state at 3.2 MPa.
2. Outdoor unit outputs
| Output | Type / function | Control range |
|---|---|---|
| Compressor 1 (inverter) | Magnetic relay | Operation coil AC220-240 V, 50 Hz |
| Compressor 2 | Magnetic relay | Operation coil AC220-240 V, 50 Hz |
| Electronic expansion valve 1 (Main) | EEV coil | Operating voltage DC12 V |
| Electronic expansion valve 2 (SC-Hex) | EEV coil | Operating voltage DC12 V |
| Fan motor | DC brushless motor | - |
| 4-way valve 1 | 4-way valve coil | AC220-240 V, 50/60 Hz, 8/5 W |
| Solenoid valve 1 | Hot gas bypass | AC220-240 V, 50 Hz, 8 W |
| Solenoid valve 2 | INV compressor pressure equalizing valve | AC220-240 V, 50 Hz, 6 W |
| Solenoid valve 3 | ACM oil return valve 1 | AC220-240 V, 50 Hz, 6 W |
| Solenoid valve 5 | EEV1 bypass valve | AC220-240 V, 50 Hz, 8 W |
| Solenoid valve 6 | INV compressor oil release valve | AC220-240 V, 50 Hz, 6 W |
| Crank case heater 1 | For inverter compressor | AC240 V, 25 W |
| Crank case heater 2 | For constant speed compressor | AC240 V, 35 W |
| Base heater | Field supply | AC220-240 V, 35 W |
3. Communication input / output
| Communication | Direction |
|---|---|
| LON WORKS | Indoor unit ↔ Outdoor unit |
| Inverter communication | Outdoor unit internal communication |
| Outdoor unit communication | Outdoor unit ↔ Outdoor unit |
4. External input / output
External inputs - dry contact
| Connector | Function | Input type |
|---|---|---|
| CN131 | Low noise mode operation | Dry contact input |
| CN132 | Cooling / Heating priority | Dry contact input |
| CN133 | Outdoor unit operation peak control | Dry contact input |
| CN134 | Emergency stop operation | Dry contact input |
External outputs
| Connector | Function | Logic | Control output |
|---|---|---|---|
| CN136 | Error display | ON = Error / OFF = Normal | DC 0 / 12-24 V, Max. 30 mA |
| CN137 | Operation display | ON = Operation / OFF = Stop | DC 0 / 12-24 V, Max. 30 mA |
5. LED display
| Display | Purpose |
|---|---|
| Single LED 101 | Displays operation, error and setting information using the single LEDs and 7-segment LED. |
| Single LED 102 | |
| 7-segment LED |
Reference note: This article reproduces the values and descriptions shown in the supplied service-information table. Where the source does not provide a control range or test method, none has been added.