Value Village ／ Everyday know-how
This answer is a draft. It stays unpublished until legal review and source verification are complete.
Almost every Japanese room has its own wall-mounted air conditioner, used for cooling in summer and heating in winter. It is the most important appliance in the home for comfort and the one most often neglected — until the smell in June tells you what has been growing inside.
| Task | Frequency | How |
|---|---|---|
| Filter | Every 2 weeks in season, monthly otherwise | Lift the front panel, slide out, vacuum the outside, wash with water if greasy, dry fully before refitting |
| Louvers and panel | Monthly | Wipe with a damp cloth |
| Dry the interior | After every cooling session | Run "internal clean" (内部クリーン) or fan-only mode for 1–2 h; many units do this automatically — do not switch off at the wall mid-cycle |
| Check the drain hose | Start of season | The outdoor drain hose (ドレンホース) should drip when cooling; if blocked (insects, dirt), water leaks indoors. A drain-hose cap stops insects entering |
| Outdoor unit | Season start | Clear leaves and objects; keep 20 cm+ clearance; do not cover |
| Professional cleaning | Every 2–4 years, more with pets or smokers | ¥10,000–15,000 per unit; they dismantle and wash the fins and fan |
| Test run | Before the first hot day (May) | Run cooling for 30 min with windows open; check smell and drip |
[Verify] Energy figures with the Agency for Natural Resources and Energy; spray-cleaner incidents with NITE and manufacturer advisories.
The filter stops dust; the mould grows behind it on wet fins. Dry the interior after use and get it washed professionally every few years.
It is mould, and it is blowing into the room. Run fan mode after cooling; book a cleaning if the smell persists.
Manufacturers say do not; residue causes faults and fires. The inside is a professional job.
Interrupting the automatic internal-clean cycle leaves the fins wet. Let it finish (the fan runs on for an hour or two).
The drain hose is meant to drip when cooling. Water dripping inside means the hose is blocked — check the outdoor end.
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https://www.enecho.meti.go.jp/category/saving_and_new/saving/general/howto/
https://www.nite.go.jp/jiko/chuikanki/
https://www.jraia.or.jp/
⚠️ Editorial note: the source URLs above were identified by search. Our working environment cannot reach go.jp domains, so the contents have not been checked against the text. Verify every source before publication and record who checked it and when.
What we share here are ideas and everyday practices passed down among people living in Japan, together with general information drawn from public sources. They are not official recommendations, and they are not professional instruction. Practices vary between households and regions.
This is general information. Results vary from person to person and depend on your own conditions and surroundings.
Please decide for yourself, using your own judgement, whether any of this suits your situation. We cannot accept responsibility for any damage, loss or injury arising from following this article.
Always follow the instructions on any product you use, and never mix cleaning products. If you rent your home, check with your landlord before making any changes.
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