GENERAL AIRSTAGE | TECHNICAL REFERENCE
ARTH18KMTAP / ARTH24KMTAP
Ducted Inverter Heat Pump – Design & Technical Manual
Outdoor Units: AOTH18KBTA / AOTH24KBTA
Technical Manual DR_AR056EF_01 | 25 October 2021 | R32 Refrigerant
This guide provides installation, performance, refrigerant, electrical and control information for the ARTH18KMTAP and ARTH24KMTAP ducted air conditioning systems.
It is intended for qualified installation and service technicians.
1. Applicable Models
| Indoor Unit | Outdoor Unit | System |
|---|---|---|
| ARTH18KMTAP | AOTH18KBTA | 5.0 kW Cooling / 6.0 kW Heating |
| ARTH24KMTAP | AOTH24KBTA | 7.1 kW Cooling / 8.0 kW Heating |
2. Technical Specifications
| Specification | 18 Class | 24 Class |
|---|---|---|
| Rated cooling capacity | 5.0 kW | 7.1 kW |
| Cooling capacity range | 0.9–6.4 kW | 1.8–8.1 kW |
| Rated heating capacity | 6.0 kW | 8.0 kW |
| Heating capacity range | 0.9–7.8 kW | 2.0–9.1 kW |
| Rated cooling input | 1.37 kW | 2.15 kW |
| Rated heating input | 1.58 kW | 2.19 kW |
| Rated cooling current | 5.9 A | 9.1 A |
| Rated heating current | 6.8 A | 9.2 A |
| Maximum operating current | 12.7 A | 13.6 A |
| Power supply | 220–240 V AC, 50 Hz | |
| Allowable voltage | 198–264 V | |
| Refrigerant | R32 | |
3. Indoor Unit Dimensions & Airflow
Indoor dimensions: 240 H × 1,000 W × 700 D mm
Indoor unit weight: 32 kg
External static pressure: 50–150 Pa
| Fan Speed | ARTH18KMTAP | ARTH24KMTAP |
|---|---|---|
| High | 1,080 m³/h | 1,500 m³/h |
| Medium | 860 m³/h | 1,170 m³/h |
| Low | 760 m³/h | 1,020 m³/h |
| Quiet | 650 m³/h | 860 m³/h |
Actual airflow will depend on ductwork resistance and the selected external static pressure setting. Refer to the fan performance curves in the design and technical manual when commissioning or investigating airflow issues.
4. External Static Pressure Settings
External static pressure is configured using Function 26 through the wired remote controller.
| Function | Setting | Description |
|---|---|---|
| 26 | 05 | 50 Pa |
| 26 | 06 | 60 Pa |
| 26 | 07 | 70 Pa |
| 26 | 08 | 80 Pa |
| 26 | 09 | 90 Pa |
| 26 | 10 | 100 Pa |
| 26 | 11 | 110 Pa |
| 26 | 12 | 120 Pa |
| 26 | 13 | 130 Pa |
| 26 | 14 | 140 Pa |
| 26 | 15 | 150 Pa |
| 26 | 31 | Standard 50 Pa – Factory Default |
| 26 | 32 | Automatic airflow adjustment |
5. Refrigerant & Piping Specifications
| Specification | AOTH18KBTA | AOTH24KBTA |
|---|---|---|
| Refrigerant | R32 | |
| Factory refrigerant charge | 1,020 g | 1,250 g |
| Pre-charged pipe length | 20 m | |
| Maximum piping length | 30 m | |
| Maximum height difference | 20 m | 25 m |
| Liquid pipe | 6.35 mm (1/4 inch) | |
| Gas pipe | 12.70 mm (1/2 inch) | |
| Connection method | Flare | |
For pipe runs exceeding the factory pre-charge length of 20 m, calculate the additional refrigerant according to Section 7, page 63 of the design and technical manual. Do not estimate the charge.
Only appropriately licensed personnel should undertake refrigerant handling.
6. Operating Temperature Range
| Mode | Outdoor Temperature Range |
|---|---|
| Cooling | -10°C to +50°C |
| Heating | -15°C to +24°C |
The specified cooling range is subject to the manufacturer's outdoor unit suction temperature conditions. Protective operation may occur outside the stated operating range.
7. Function Settings
Function settings can be configured using the compatible wired remote controller.
| Function | Description |
|---|---|
| 11 | Filter notification interval |
| 26 | External static pressure |
| 30 / 31 | Indoor temperature sensor correction – Cooling / Heating |
| 35 / 36 | Wired controller temperature sensor correction |
| 40 | Automatic restart following power interruption |
| 42 | Temperature sensor switching |
| 43 | Cold air prevention |
| 44 | Wireless controller custom code |
| 46 | External input operation / forced stop |
| 48 | Auxiliary temperature sensor selection |
| 49 | Indoor fan energy-saving control during cooling |
| 60 | External output functions |
Function 42 – Temperature Sensor Selection
| Setting | Description |
|---|---|
| 00 | Indoor unit temperature sensor – Factory Default |
| 01 | Both indoor and wired remote controller sensors |
Function 48 – Auxiliary Temperature Sensor
| Setting | Description |
|---|---|
| 00 | Both sensors |
| 01 | Wired remote controller sensor only – Factory Default |
Important: Function 48 requires Function 42 to be configured as 01.
Function 46 – External Input Control
| Setting | Description |
|---|---|
| 00 | Operation / Stop mode 1 – Factory Default |
| 01 | Setting prohibited |
| 02 | Forced stop |
| 03 | Operation / Stop mode 2 |
Function 60 – External Output
| Setting | Output Function |
|---|---|
| 00 | Operation status – Factory Default |
| 01–08 | Setting prohibited |
| 09 | Error status |
| 10 | Indoor fan operating status |
| 11 | External heater output |
8. External Input and Output Connections
The indoor PCB supports external input and output functions through designated terminals and connectors.
| Connection | Function |
|---|---|
| Indoor input terminal 1–2 | Operation / Stop or Forced Stop |
| CN47 | External output connection |
| CN75 | Optional external input/output PCB connection |
CN47 output specifications:
- High output: DC 12 V ± 2 V
- Low output: 0 V
- Maximum permissible current: 50 mA
- Recommended cable: Twisted pair, 22 AWG
- Maximum output cable length: 25 m
External input cable: Twisted pair 22 AWG, maximum 150 m, separated from power cabling.
For optional UTY-XCSX external input/output PCB wiring, refer to the manual's detailed dry-contact, applied-voltage and relay wiring diagrams.
9. Group Control
The wired controller group connection arrangement supports:
- Up to 16 indoor units in a group control system.
- Maximum total remote controller cable length: 500 m.
- Non-polar 2-wire remote controller connection.
- Polar 3-wire remote controller connection.
Non-polar 2-wire systems use automatic controller address allocation during initial startup. Polar 3-wire systems require appropriate remote controller addressing. In manual addressing arrangements, the manual specifies a maximum of 15 indoor units.
10. Outdoor Unit Specifications
| Specification | AOTH18KBTA | AOTH24KBTA |
|---|---|---|
| Dimensions H × W × D | 632 × 799 × 290 mm | 716 × 820 × 315 mm |
| Net weight | 36 kg | 42 kg |
| Compressor type | DC Twin Rotary | |
| Cooling outdoor airflow | 2,020 m³/h | 2,150 m³/h |
| Heating outdoor airflow | 1,830 m³/h | 2,440 m³/h |
| Sound pressure – Cooling | 48 dB(A) | 48 dB(A) |
| Sound pressure – Heating | 49 dB(A) | 50 dB(A) |
11. Compatible Controllers
| Model | Description |
|---|---|
| UTY-RNRT* | Touchscreen wired controller – Non-polar 2-wire |
| UTY-RNRYT* | Wired controller – Non-polar 2-wire |
| UTY-RVNYN | Wired controller – Polar 3-wire |
| UTY-RSRYT | Simple wired controller – Non-polar 2-wire |
| UTY-RHRYT | Simple wired controller – Non-polar 2-wire |
| UTY-RSNYN | Simple wired controller – Polar 3-wire |
| UTY-LBTYM | Wireless remote and IR receiver kit |
12. Optional Accessories and Interfaces
| Accessory | Description |
|---|---|
| UTY-XSZX | Remote temperature sensor |
| UTD-LFDB | Long-life air filter |
| UTY-XWZXZG | External output connection kit |
| UTY-XCSX | External input/output PCB |
| UTZ-GXDA | External input/output PCB box |
| UTY-CDPXZC / UTY-CDPXZD | Zone control interface – Polar 3-wire |
| UTY-CDRXZC / UTY-CDRXZD | Zone control interface – Non-polar 2-wire |
| UTY-VMSX | Modbus converter |
| UTY-VKSX | KNX converter |
| UTY-VTGX / UTY-VTGXV | Network converters |
| UTY-TERX | External switch controller |
13. Service and Commissioning Notes
- Confirm the indoor and outdoor model pairing.
- Verify supply voltage and power connections.
- Check return air, supply air and ductwork restrictions.
- Confirm Function 26 external static pressure settings.
- Check refrigerant pipe length and any additional charge requirement.
- Confirm temperature sensor selection and controller function settings.
- Check external control signals where fitted.
- Review installation clearances and outdoor unit airflow restrictions.
- Refer to the applicable wiring diagrams before electrical diagnosis.
Always isolate the power supply before accessing internal electrical components. Refrigerant, electrical and mechanical servicing must be undertaken by appropriately qualified personnel.
Refer to the relevant installation manual and the complete technical manual for detailed diagrams, installation requirements and model-specific service procedures.
Technical Reference: ARTH18KMTAP / ARTH24KMTAP
Source: Design & Technical Manual DR_AR056EF_01 – 25 October 2021
Specifications and product information may be subject to change.