This document covers the specifications for the indoor model ARTH24KMTA and its corresponding outdoor unit AOTH24KCTA (inverter heat pump system).
Electrical Data
The system operates on a 220–240V ~ 50Hz supply, with an available voltage range of 198–264V, and the indoor unit is powered via the outdoor unit. Electrical characteristics for the outdoor unit specify a maximum operating current of 20A (total of indoor + outdoor) and a starting current of 8.4A, with a 25A circuit breaker, 4.0 mm² power cable, 1.5 mm² connection cable, and a maximum connection wiring length of 76 m.
Cooling Performance
The ARTH24KMTA provides a rated cooling capacity of 7.1 kW (24,200 Btu/h) with a capacity range of 3.3–8.5 kW (11,300–29,000 Btu/h). Rated cooling input power is 1.85 kW (maximum 2.72 kW), with a rated operating current of 8.0A and an EER of 3.84 kW/kW. Seasonal performance values (commercial method) are TCSPF 4.98 (hot climate), 5.01 (average climate), and 5.30 (cool climate), and moisture removal is 1.7 L/h (3.0 pints/h).
Heating Performance
The unit provides a rated heating capacity of 8.0 kW (27,300 Btu/h) with a capacity range of 3.6–10.5 kW (12,300–35,800 Btu/h). Rated heating input power is 1.93 kW (maximum 2.89 kW), with a rated operating current of 8.4A and a COP of 4.15 kW/kW. Seasonal heating performance (commercial method) is HSPF 4.40 (hot climate), 4.56 (average climate), and 4.23 (cool climate).
Fan Motor, Airflow, Static Pressure, and Noise
Indoor fan input power is 155W (High), 77W (Med), 53W (Low), and 37W (Quiet). Airflow rate (cooling and heating) is 1,500 m³/h (High), 1,170 m³/h (Med), 1,020 m³/h (Low), and 860 m³/h (Quiet), using a sirocco fan ×2 with 197W motor output, and a static pressure range of 50–150 Pa. Sound pressure level is 38/33/30/27 dB(A) (High/Med/Low/Quiet) for both cooling and heating, and sound power level is 62 dB(A).
Heat Exchanger, Construction, Dimensions, and Piping
The indoor heat exchanger dimensions are 336 × 790 × 39.9 mm, with 1.4 fin pitch, 3 × 16 rows × stages, copper pipe, and aluminium fins, housed in a steel sheet enclosure. Indoor unit dimensions are 240 × 1,000 × 700 mm (net) and 334 × 1,225 × 883 mm (gross), with weight 32 kg (net) and 37 kg (gross). Connection piping is Ø6.35 mm (1/4”) liquid and Ø12.70 mm (1/2”) gas with flare connections. The drain port and drain hose are PVC, with tip diameter Ø25 (I.D.) / Ø32 (O.D.). Operating range is 18–32°C (cooling, 80%RH or less) and 16–30°C (heating), the controller is wired (option: simple remote controller / IR receiver unit), and the indoor IP rating is IPX0.
Outdoor Unit Specifications – AOTH24KCTA
The AOTH24KCTA operates on 220–240V ~ 50Hz (available 198–264V) and has a starting current of 8.4A. Airflow rate is 3,910 m³/h (cooling) and 3,770 m³/h (heating) via a propeller fan ×1 with 120W motor output. Sound pressure level is 48 dB(A) (cooling) and 50 dB(A) (heating), with sound power level 67 dB(A). The heat exchanger consists of Main 1: 956 × 905 × 18.19 mm and Main 2: 956 × 905 × 18.19 mm, with 1.45 fin pitch on both coils and 1 × 46 rows × stages on each, using copper tube and aluminium fins with blue fin surface treatment. The compressor is DC twin rotary with 2,180W motor output, refrigerant is R32 with a charge of 1,800 g, and refrigerant oil is RmM68AF (800 cm³). The enclosure is steel sheet, colour beige (approx. Munsell 10YR 7.5/1.0), dimensions are 998 × 940 × 320 mm (net) and 1,176 × 1,027 × 445 mm (gross), and weight is 63 kg (net) and 72 kg (gross). Connection piping is Ø6.35 mm (1/4”) liquid and Ø12.70 mm (1/2”) gas with flare connections, with 50 m pre-charge length, 75 m maximum length, and 30 m maximum height difference. Operating range is −10 to 50°C (cooling) and −15 to 24°C (heating), the drain hose material is LDPE with tip diameter Ø13.0 (I.D.) / Ø16.0–Ø16.7 (O.D.), and the outdoor IP rating is IPX4.
Safety Devices – AOTH24KCTA
Circuit protection is provided by the main PCB current fuses rated at 250V 30A or 35.5A, 250V 3.15A, and 250V 10A ×2. Fan motor protection uses a terminal protection program that activates at 150 ±15°C to stop the fan motor and resets at 120 ±15°C to restart it. Compressor protection includes discharge temperature protection that activates at 110°C (compressor stop) and resets after 7 minutes (compressor restart), compressor temperature protection that activates at 108°C (stop) and resets at 80°C or less (restart), and outdoor temperature protection (only in COOL or DRY mode) that activates at −20°C (stop) and resets at −15°C (restart).