General Assist Technical Reference

ASTG18KMCB / ASTG22KMCB / ASTG24KMCB

Operation, timers, airflow, energy-saving functions and troubleshooting
Wall mounted R32 air conditioner operating guide
Models covered: ASTG18KMCB, ASTG22KMCB and ASTG24KMCB. This guide summarises the main day-to-day operating functions and user-level troubleshooting from the operating manual.
R32 refrigerant: This product contains flammable R32 refrigerant and must only be installed or serviced by qualified personnel. Keep refrigerant away from ignition sources and follow the applicable installation and service requirements.
Built-in Wireless LAN: ASTG18KMCB / ASTG22KMCB / ASTG24KMCB include a built-in WLAN adapter for wireless LAN control. The indoor unit has dedicated Wireless LAN control indicators and buttons. Refer to the Wireless LAN setting manual for pairing and app setup.

1. Quick operation

FunctionOperation
Start / StopPress START/STOP.
Operating modePress MODE: AUTO → COOL → DRY → FAN → HEAT.
TemperatureAUTO / COOL / DRY: 18–30 °C. HEAT: 16–30 °C. Temperature control is not available in FAN mode.
Fan speedAUTO → HIGH → MED → LOW → QUIET.
Heating start-up: At the beginning of HEAT operation the indoor fan may run at very low speed for approximately 3–5 minutes while the unit warms internally. Automatic defrosting can also temporarily override heating operation.

POWERFUL operation

POWERFUL operation runs the system at maximum power and strong airflow to cool or heat the room quickly. It automatically ends when the room reaches the set temperature or after approximately 20 minutes. POWERFUL cannot operate at the same time as ECONOMY, and it temporarily overrides Outdoor Unit Low Noise and Energy Saving functions.

10 °C HEAT

10 °C HEAT maintains the room at approximately 10 °C to help prevent the temperature falling too low. The ECONOMY indicator turns green while this function is active. Only vertical airflow direction can be adjusted during 10 °C HEAT.

Outdoor Unit Low Noise

This function reduces outdoor-unit noise by lowering compressor rotation and outdoor fan speed. The setting is retained even after the indoor unit is stopped. It cannot be used together with FAN, DRY or POWERFUL operation.

2. Airflow direction and swing

These models provide both vertical and horizontal motorised airflow control.

ControlAvailable positions / operation
Vertical airflow8 positions using the Vertical SET button.
Horizontal airflow5 positions using the Horizontal SET button.
SWINGCycles through Up/Down, Left/Right, Up/Down + Left/Right, and Stop Swing.
Cooling / Dry airflow: If the vertical louver is kept in positions 5–8 for more than 30 minutes in COOL or DRY mode, it automatically returns to position 4 to reduce the risk of condensation and water droplets.

3. Timer operation

Before setting timers, make sure the remote controller clock and day of the week are correct.

TimerPurpose
ON timerStarts the unit at the selected time.
OFF timerStops the unit at the selected time.
Program timerCombines ON and OFF timing within a 24-hour period.
Sleep timerGradually adjusts temperature for comfort, then turns the air conditioner off after the selected period.
Weekly timerUp to 4 ON/OFF reservations per day and up to 28 reservations per week.

ON / OFF timer setup

  1. Press TIMER SETTING.
  2. Use SELECT to choose ON, OFF or ON↔OFF.
  3. Press NEXT.
  4. Use SELECT to set the time.
  5. Press SEND while close to the indoor unit.

Weekly timer

The Weekly Timer supports four programs per day. Each program can be set as ON, OFF or unused. For ON programs, a temperature can also be specified. AUTO / COOL / DRY can be set from 18–30 °C; HEAT can be set to 10 °C or 16–30 °C.

Timer after power interruption: A blackout or breaker interruption can make the internal clock incorrect. The indoor TIMER indicator will blink; reset the clock and timer settings before relying on scheduled operation.

4. Energy-saving functions

ECONOMY

ECONOMY reduces maximum output to approximately 70% of normal operation and moderates the room temperature. In COOL / DRY, the room is controlled a few degrees warmer than the set temperature; in HEAT, a few degrees cooler.

Human Sensor Energy Saving

The Energy Saving program is enabled at the factory. If no movement is detected for approximately 20 minutes, the set temperature is adjusted to reduce energy use. When someone returns, the unit automatically returns to the original setting.

ModeNo person detected
COOL / DRYSet temperature increases by up to approximately 2 °C.
HEATSet temperature decreases by up to approximately 4 °C.
AUTOEnergy-saving behaviour follows the active cooling, heating or dry mode.

The sensor detects infrared movement and has an approximate range of 7 m, 90° vertically and 100° horizontally. Detection may be affected by room temperature, people remaining still, furniture, glass, thick clothing, pets, moving curtains, plants, heaters, humidifiers and oscillating fans.

Demand Response

The system supports Air Conditioning Demand Response where available through the electricity supplier. When active, the OPERATION indicator blinks and cooling or heating capacity can be reduced.

DR modeOperation
DR1Compressor off.
DR2Energy consumption limited to no more than 50% of rated energy consumption over a half-hour period.
DR3Energy consumption limited to no more than 75% of rated energy consumption over a half-hour period.

5. Remote control, wired control and Wireless LAN

Remote controller custom code

Where two or more air conditioners are installed in the same room, the wireless remote controller can be assigned one of four custom codes: A, B, C or D. The indoor unit and remote controller must use the same code. Both are set to code A from the factory.

  1. Stop operation so only the clock is shown on the remote controller.
  2. Press and hold MODE for at least 5 seconds to display the current custom code.
  3. Use the temperature buttons to select A, B, C or D.
  4. Press MODE again to return to the clock display.
Important: Changing the remote controller code does not change the indoor unit code. The indoor unit custom code must be configured to match by authorised service personnel. The remote code may also return to A after battery replacement.

Optional wired remote controller

An optional wired remote controller can be used with the wireless remote. Some wireless functions become restricted depending on the wired controller type.

Wired controller typeRestricted wireless functions
Polar 3-coreOutdoor Unit Low Noise, Energy Saving, 10 °C HEAT, POWERFUL and timer operation.
Non-polar 2-coreOutdoor Unit Low Noise, 10 °C HEAT, Weekly Timer and POWERFUL.

Built-in Wireless LAN control

The WLAN adapter is built into the indoor unit. The manual directs users to the dedicated Wireless LAN setting manual for connection and app configuration. The Wireless LAN indicators can be turned off through the mobile app.

TEST RUN button

The TEST RUN button is for initial installation testing only and should not be used during normal operation. During Test Run, the OPERATION and TIMER indicators blink simultaneously. If started accidentally, stop the unit using the Start/Stop button.

6. Cleaning and maintenance

Before cleaning: Stop the air conditioner and disconnect the power supply. Do not touch the aluminium heat-exchanger fins.

Under normal use, clean the air filters approximately every 2 weeks. Dust can be removed with a vacuum cleaner, or the filters can be washed using neutral household detergent and warm water. Dry them thoroughly in the shade before refitting.

Filter indicator (installer setting): If this function has been enabled during installation, the ECONOMY indicator blinks when filter cleaning is due. After cleaning, press the indoor unit MANUAL AUTO button for less than 3 seconds to reset the filter indicator.
Air cleaning filterPart number / maintenance
Apple-catechin filterUTR-FA16. Disposable; do not wash or reuse. Replace approximately every 3 months under normal use.
Ion deodorization filterUTR-FA16-2. Clean approximately every 3 months and replace approximately every 3 years under normal use.

If the indoor unit has not been used for one month or more, run FAN mode for half a day to dry the internal components before returning to normal operation.

7. Normal operating characteristics

  • Restart delay: Compressor start can be delayed by approximately 3 minutes after a sudden OFF → ON power change.
  • Defrost: Heating may stop for up to approximately 15 minutes while the outdoor unit defrosts. The OPERATION indicator blinks.
  • Water / steam outdoors: Water or steam can be produced during heating defrost and is normal.
  • Low airflow in heating: Fan speed may remain very low during warm-up or when room temperature is above the set temperature.
  • Dry mode: Indoor fan operates at low speed and may stop intermittently for humidity control.
  • Noise: Refrigerant flow, panel expansion/contraction and sizzling during defrost can be normal.

8. Troubleshooting

SymptomChecks
Does not operateCheck breaker, power outage, fuse / circuit breaker trip and timer settings.
Poor cooling or heatingCheck dirty filters, blocked inlet/outlet, temperature setting, open doors/windows, direct sunlight, internal heat loads, QUIET fan speed, Outdoor Unit Low Noise and Demand Response operation.
Different from remote settingCheck remote-control batteries and battery installation.
Airflow weak or stoppedMay be normal during heating warm-up, defrost, DRY mode, QUIET mode, AUTO monitoring or when the outdoor unit has stopped.
Stop operation immediately and isolate power if the unit smells of burning, emits smoke, leaks water, or if the problem persists after the checks above. The manual also directs service attention where the OPERATION and TIMER indicators blink while the ECONOMY indicator is blinking rapidly.
Wireless LAN troubleshooting: For WLAN control faults or connection issues, use the dedicated Wireless LAN setting manual or the mobile app guidance rather than the general operating troubleshooting table.
Source: Operating Manual Part No. 9320455040 for ASTG18KMCB / ASTG22KMCB / ASTG24KMCB. Refer to the original operating and installation manuals for full safety, installation and service requirements.