Installation Manual (View Online) – KMCD Series (R32): Indoor ASTH07KMCD, ASTH09KMCD, ASTH12KMCD, ASTH14KMCD + Outdoor AOTH07KMCD, AOTH09KMCD, AOTH12KMCD, AOTH14KMCD

Applies to:
Indoor (Wall-Mounted): ASTH07KMCD / ASTH09KMCD / ASTH12KMCD / ASTH14KMCD
Outdoor: AOTH07KMCD / AOTH09KMCD / AOTH12KMCD / AOTH14KMCD
Refrigerant: R32
Audience: Authorised service personnel / professional installers

Contents

1) Safety and compliance

  • Installation and servicing must be completed by qualified and experienced personnel only.
  • Do not energise the system until all installation work is complete.
  • After isolating power, wait before touching electrical components (observe the manufacturer guidance for discharge time).
  • If refrigerant leakage occurs during works: ventilate immediately and remove ignition sources.
  • Use vacuum pump evacuation (do not purge with refrigerant).
  • Ensure correct grounding/earthing and earth leakage protection as required by local regulations.

2) R32 refrigerant requirements

  • R32 operates at higher pressures than legacy systems; only use R32/R410A-rated tools, hoses and materials.
  • Charging port thread for R32/R410A: 1/2–20 UNF.
  • Prevent moisture/foreign matter entering piping; seal pipe ends during storage/handling.
  • Leak detection must be suitable for flammable refrigerants; do not use open flame methods.
  • Comply with relevant safety standards and local regulations for flammable refrigerants.

3) Tools and materials (R32/R410A rated)

  • High-pressure gauge manifold suitable for R32/R410A
  • R32/R410A charging hoses
  • Vacuum pump and appropriate adapters (as required)
  • R32/R410A compatible leak detector
  • Tube cutter, deburr tool, flare tool suitable for R32/R410A, torque wrenches for flare nuts and caps
  • Nitrogen cylinder + regulator for pressure testing

4) System overview (what powers what)

  • Indoor unit is powered from the outdoor unit. Do not provide a separate power supply to the indoor unit unless explicitly specified by local product documentation.
  • Confirm indoor-to-outdoor terminal numbering matches on both ends and that cable routing avoids contact with refrigerant piping.

5) Refrigerant piping requirements

5.1 Copper pipe material and minimum wall thickness (R32/R410A)

  • Use seamless phosphor deoxidised copper.
  • Do not reuse existing piping (risk of contamination and incompatibility).

Minimum wall thickness (annealed copper) by pipe outside diameter (text version of the table):

  • 6.35 mm outside diameter (nominal size 1/4"): minimum thickness 0.80 mm
  • 9.52 mm outside diameter (nominal size 3/8"): minimum thickness 0.80 mm
  • 12.70 mm outside diameter (nominal size 1/2"): minimum thickness 0.80 mm
  • 15.88 mm outside diameter (nominal size 5/8"): minimum thickness 1.00 mm
  • 19.05 mm outside diameter (nominal size 3/4"): minimum thickness 1.20 mm

5.2 Refrigerant connection pipe sizes by indoor unit model (no abbreviations)

Use the indoor unit model number below to identify the required liquid pipe size and gas pipe size:

  • ASTH07KMCD: Liquid pipe size Ø 6.35 mm (1/4"); Gas pipe size Ø 9.52 mm (3/8")
  • ASTH09KMCD: Liquid pipe size Ø 6.35 mm (1/4"); Gas pipe size Ø 9.52 mm (3/8")
  • ASTH12KMCD: Liquid pipe size Ø 6.35 mm (1/4"); Gas pipe size Ø 9.52 mm (3/8")
  • ASTH14KMCD: Liquid pipe size Ø 6.35 mm (1/4"); Gas pipe size Ø 9.52 mm (3/8")
  • Always insulate both liquid and gas lines. Increase insulation thickness in high humidity environments.
  • Keep pipe ends sealed until final flaring/connection to prevent moisture ingress.

5.3 System piping limits (outdoor unit reference)

  • Maximum piping length: 20 m
  • Maximum height difference (indoor unit to outdoor unit): 15 m

6) Electrical requirements

6.1 Outdoor unit power supply (AOTH07KMCD, AOTH09KMCD, AOTH12KMCD, AOTH14KMCD)

  • Supply: 220–240V ~ 50Hz, operating range 198–264V
  • Breaker capacity (reference):
    • AOTH07KMCD: 10 A
    • AOTH09KMCD: 10 A
    • AOTH12KMCD: 10 A
    • AOTH14KMCD: 15 A
  • Power supply cable: minimum 1.5 mm², 2-core + earth (select per local code)
  • Earth leakage protection: use ELCB/RCD as required (manual reference notes 30 mA)

6.2 Indoor to outdoor connection cable (ASTH07KMCD, ASTH09KMCD, ASTH12KMCD, ASTH14KMCD)

  • Connection cable: minimum 1.5 mm², Type 60245 IEC 57, 3-core + earth
  • Limit voltage drop to less than 2%; increase conductor size if required.
  • Do not connect AC supply to transmission terminals.

7) Outdoor unit installation (AOTH07KMCD, AOTH09KMCD, AOTH12KMCD, AOTH14KMCD)

7.1 Location and mounting

  • Install on a base that can withstand weight and vibration; use anchor bolts and appropriate anti-vibration measures.
  • Do not install where combustible gas may accumulate or in corrosive environments.
  • Secure appropriately for local wind/weather conditions.

7.2 Drain installation (outdoor)

  • If outdoor temperature is 0°C or less, do not use accessory drain pipe (freeze risk).
  • Heating operation produces drain water; connect to suitable drain hose where applicable.
  • Seal unused drain holes to prevent leakage.

8) Indoor unit installation (ASTH07KMCD, ASTH09KMCD, ASTH12KMCD, ASTH14KMCD)

8.1 Site selection (minimum requirements)

  • Install level on a strong wall not subject to vibration.
  • Ensure inlet/outlet are unobstructed and airflow reaches the room.
  • Install at least 1 m away from TV/radio to reduce interference.
  • Install height from floor: greater than 1.8 m.
  • Allow service access for filter removal and maintenance.

8.2 Wall hole and bracket

  • Wall hole diameter: 65 mm
  • Outside end must be lower by 5 to 10 mm than inside end.
  • Always use a wall pipe; without it, the indoor-to-outdoor cable may contact metal and cause hazards.
  • Install wall hook bracket level; fasten securely and confirm no movement.

8.3 Indoor piping direction (summary)

  • Piping can connect in multiple directions (right, left, rear, and bottom variants). Use the unit guided cut-outs as required.
  • Arrange drain hose at the bottom when taping refrigerant piping and drain hose together.
  • For left-side drain routing, interchange drain cap and drain hose per manufacturer procedure and confirm no gaps.

9) Pressure test, evacuation, commissioning

9.1 Flare work – tightening torques (system)

Flare nut tightening torque by pipe size (text version of the table):

  • 1/4" pipe size (outside diameter 6.35 mm): 16–18 N·m
  • 3/8" pipe size (outside diameter 9.52 mm): 32–42 N·m
  • 1/2" pipe size (outside diameter 12.70 mm): 49–61 N·m
  • 5/8" pipe size (outside diameter 15.88 mm): 63–75 N·m
  • 3/4" pipe size (outside diameter 19.05 mm): 90–110 N·m

9.2 Nitrogen pressure test (outdoor reference)

  • With valves closed, pressurise with nitrogen to 4.15 MPa.
  • Check all flare joints and brazed points; rectify any leakage and retest.

9.3 Vacuum evacuation

  • Evacuate to -0.1 MPa (-76 cmHg) and run vacuum pump for at least 15 minutes.
  • Open service valves after evacuation and refit caps to specified torques.

9.4 Service valve and charging port cap tightening torques (outdoor reference)

Service valve cap and port cap tightening torques (text version of the table):

  • Blank cap (applicable sizes 1/4" and 3/8"): 20–25 N·m
  • Blank cap (applicable size 1/2"): 28–32 N·m
  • Blank cap (applicable size 5/8"): 30–35 N·m
  • Blank cap (applicable size 3/4"): 35–40 N·m
  • Charging port cap (R32/R410A): 12.5–16 N·m

10) Additional refrigerant charging (Outdoor unit: AOTH07KMCD, AOTH09KMCD, AOTH12KMCD, AOTH14KMCD)

  • Factory charge supports 15 m pipe length. Additional charge is required beyond 15 m.
  • Charging guideline: 20 g per metre beyond 15 m (up to maximum piping length).
  • Example: at 20 m total piping length, additional charge is +100 g.

Maximum total charge (per outdoor unit model)

  • AOTH07KMCD: Maximum total charge 800 g (700 g factory charge + 100 g additional charge)
  • AOTH09KMCD: Maximum total charge 950 g (850 g factory charge + 100 g additional charge)
  • AOTH12KMCD: Maximum total charge 950 g (850 g factory charge + 100 g additional charge)
  • AOTH14KMCD: Maximum total charge 1040 g (940 g factory charge + 100 g additional charge)

11) Indoor function settings (ASTH reference)

  • Confirm outdoor wiring is completed and covers are fitted before function settings.
  • Enter function setting mode (wireless remote): while pressing [POWERFUL] and [TEMP ( )] simultaneously, press [RESET].
  • Select function number with TEMP; change setting value with POWERFUL; confirm with MODE; fix with START/STOP; cancel with RESET.
  • After completing, power-cycle the system (wait before reconnecting as per manufacturer guidance).

Common function examples (reference)

  • 11 Filter sign interval: 400 hours / 1000 hours / 200 hours / No indication (factory default may be No indication).
  • 40 Auto restart: Enable (factory default) / Disable.
  • 44 Remote controller custom code: A (factory default) / B / C / D.
  • 46 External input control: Operation/Stop mode or Forced stop mode (depends on configured mode).
  • 60 External output function: Operation status / Error status / Fan operation status.

12) Test run and handover

12.1 Check items

  • Remote controller operation and indicator lamps normal
  • Airflow and louvers operate normally
  • Drainage is normal (no indoor water leakage)
  • No abnormal noise or vibration
  • No refrigerant leakage detected

12.2 Test run methods (ASTH reference)

  • Wait at least 1 minute after connecting power before starting test run.
  • Indoor unit button method: press and hold indoor unit button for more than 10 seconds; end by remote START/STOP.
  • Wireless remote: press START/STOP then TEST RUN (if applicable per remote model).
  • Do not operate test run longer than necessary.

12.3 Customer guidance

  • Explain operation, mode selection, temperature setting, timers, airflow direction.
  • Explain filter removal/cleaning and basic care requirements.
  • Provide applicable operation manuals to the customer/end user.

13) Pump down (forced cooling operation) – Outdoor unit reference

  • Use pump down for relocation/disposal refrigerant recovery in accordance with the manufacturer procedure.
  • Initiate forced cooling/test run mode per controller guidance (method varies by indoor controller type).
  • Close the 2-way valve fully, then close the 3-way valve after a short run period, then stop operation.
  • Do not proceed if refrigerant is depleted due to damaged piping; confirm leak-free condition first.

14) Error codes (ASTH reference list)

Errors may be indicated by indoor LED blink patterns (wireless) or displayed on wired remote controllers (optional). For field efficiency, capture the code, verify wiring and communication integrity, and follow a standard diagnostic workflow.

Error code list (one-line format):

  • 11 – Serial communication error
  • 12 – Wired remote controller communication error
  • 15 – Check run unfinished / automatic airflow adjustment error
  • 16 – Peripheral unit transmission printed circuit board connection error
  • 18 – External communication error
  • 21 – Unit number / address setting error (system dependent)
  • 22 – Indoor unit capacity error
  • 23 – Combination error
  • 24 – Connection unit number error (system dependent)
  • 26 – Indoor unit address setting error
  • 27 – Primary/secondary unit setup error (system dependent)
  • 29 – Connection unit number error in wired remote controller system
  • 31 – Power supply interruption error
  • 32 – Indoor unit printed circuit board model information error
  • 33 – Indoor unit motor electricity consumption detection error
  • 35 – Manual auto switch error
  • 39 – Indoor unit power supply error for fan motor
  • 3A – Indoor unit communication circuit (wired remote controller) error
  • 41 – Room temperature sensor error
  • 42 – Indoor unit heat exchanger middle temperature sensor error
  • 44 – Occupancy sensor error
  • 51 – Indoor unit fan motor error
  • 53 – Drain pump error
  • 54 – Electric air cleaner reverse VDD error
  • 55 – Filter set error
  • 57 – Damper error
  • 58 – Intake grille error
  • 59 – Indoor unit fan motor 2 error (left side fan)
  • 5A – Indoor unit fan motor 3 error (right side fan)
  • 5U – Indoor unit error
  • 61 – Outdoor unit phase and wiring error
  • 62 – Outdoor unit main printed circuit board model information error / communication error
  • 63 – Inverter error
  • 64 – Active filter error / power factor correction circuit error
  • 65 – Trip terminal error / intelligent power module temperature error
  • 68 – Rush current limiting resistor temperature rise error
  • 6A – Display printed circuit board microcomputer communication error
  • 71 – Discharge temperature sensor error
  • 72 – Compressor temperature sensor error
  • 73 – Outdoor unit heat exchanger liquid temperature sensor error
  • 74 – Outdoor temperature sensor error
  • 75 – Suction gas temperature sensor error
  • 76 – 2-way valve temperature sensor error / 3-way valve temperature sensor error
  • 77 – Heat sink temperature sensor error
  • 82 – Sub-cool heat exchanger gas inlet/outlet temperature sensor error
  • 83 – Liquid pipe temperature sensor error
  • 84 – Current sensor error
  • 86 – Discharge pressure sensor error / suction pressure sensor error / high pressure switch error
  • 94 – Trip detection
  • 95 – Compressor rotor position detection error (permanent stop)
  • 97 – Outdoor unit fan motor 1 error
  • 98 – Outdoor unit fan motor 2 error
  • 99 – 4-way valve error
  • 9A – Expansion valve (coil) error
  • A1 – Discharge temperature error
  • A3 – Compressor temperature error
  • A4 – High pressure error
  • A5 – Low pressure error
  • AC – Heat sink temperature error
  • J2 – Branch boxes error (system dependent)

Document control: This Solution article is intended as a consolidated, text-only field reference for the KMCD series installation. Always comply with local regulations and refer to the latest manufacturer documentation for detailed diagrams, part numbers, and regional variations.