Air conditioners for a 6-mat room in Japan: 5 on noise and power cost

Air conditioner for a 6-mat room in Japan: five 2.2 kW models
Fujitsu General is quietest indoors at 55 dB; Mitsubishi ZW publishes 34 dB on quiet
Toshiba is the cheapest at ¥49,300; Panasonic adds nanoe X and wi-fi

The five

Best for	Where to get it	Score	Unit price, incl. tax
The quietest indoor unit here — 55 dB cooling and heating — if you can’t decide	Fujitsu General nocria L series See price	82/100	¥86,742 (street price)
Publishes noise at four fan speeds — 34 dB on quiet	Mitsubishi Electric Kirigamine Z series See price	72/100	¥186,000 (street price)
250 mm tall, 57 dB, and the cheapest here	Toshiba Daiseikai V-M series See price	72/100	¥49,300 (street price)
Nanoe X internal cleaning, and the second-best reviewed here	Panasonic Eolia J series See price	67/100	¥60,000 (street price)
The most-reviewed here, with quiet-mode noise published	Mitsubishi Electric Kirigamine GV series See price	63/100	¥55,300 (street price)

These are sold on Rakuten Ichiba, which generally ships within Japan only, and they run on Japanese mains power (100V, 50/60Hz). They suit a home in Japan rather than a suitcase.

The quietest indoor unit here — 55 dB cooling and heating

Fujitsu General nocria L series

Part of Fujitsu General’s nocria range
Outdoor unit is 54–56 dB, which matters if your balcony backs onto a neighbour’s window
About ¥19,530 a year in electricity at ¥31 a kilowatt-hour

See today’s price on Rakuten→

Why it made the five

55 dB cooling and 55 dB heating — the quietest indoor unit of the nine
APF 6.6 and 630 kWh a year, meeting 100 per cent of the 2027 target
No automatic filter cleaning, by design — simpler to maintain yourself
Indoor unit 298 × 799 × 305 mm, 11.0 kg
Right for: A bedroom, and anyone who would rather clean a filter than maintain a cleaning mechanism.
Not for: Wanting automatic filter cleaning.
Worth knowing: Heating output at 2°C is 3.0 kW, below the 4.5 and 4.1 kW of the Hitachi and Mitsubishi flagships. At ¥86,742 it costs about ¥30,000 more than the APF 5.8 machines. Only two reviews across the sites we checked.

Score breakdown — 82/100

Criterion	Stars	Why
Quality	★★★★☆	APF 6.6 earns four stars; heating at 2°C is 3.0 kW, short of 3.3
Value for money	★★★★☆	¥86,742 plus ten years at ¥19,530 — ¥282,042 in all
Easy to live with	★★★★★	55 dB on the louder of the two measurements: the maximum
Trust	★★☆☆☆	4.73 from 2 reviews
Only here	★★★★★	The only model at 55 dB on both measurements, and the only one meeting the 2027 target without a filter-cleaning mechanism

Publishes noise at four fan speeds — 34 dB on quiet

Mitsubishi Electric Kirigamine Z series

The premium Kirigamine
Cooling 58/50/45/34 dB and heating 59/50/45/39 dB across four settings
Only the two Kirigamine models here publish a quiet-mode figure
APF 6.9

See today’s price on Rakuten→

Why it made the five

Noise at four fan speeds; 34 dB on quiet cooling
104 per cent of the 2027 efficiency target — the only one here above 100
4.1 kW of heating at 2°C, about 1.6 times its rated output
603 kWh a year
Right for: A bedroom where noise matters, and wanting the efficiency target cleared.
Not for: Having little depth to spare on the wall.
Worth knowing: At 389 mm deep and 16 kg, the indoor unit is the bulkiest here — measure before ordering. The specification sheet does not mention an internal cleaning function. Released in October 2025 and still with no reviews on the sites we checked.

Score breakdown — 72/100

Criterion	Stars	Why
Quality	★★★★★	APF 6.9 earns four stars, and 4.1 kW at 2°C earns the fifth
Value for money	★★☆☆☆	¥186,000 plus ten years at ¥18,693 — ¥372,930 in all
Easy to live with	★★★★☆	59 dB at full speed on the louder measurement; the 295 mm height earns nothing
Trust	★☆☆☆☆	No reviews found on any of the three sites
Only here	★★★★★	The only model publishing four fan speeds down to 34 dB, and the only one above 100 per cent of the 2027 target

250 mm tall, 57 dB, and the cheapest here

Toshiba Daiseikai V-M series

Fits above a curtain rail where taller units will not
About ¥22,227 a year in electricity at APF 5.8
Rated to operate between −15 and 50°C outside

See today’s price on Rakuten→

Why it made the five

Indoor unit 250 mm tall and under 800 mm wide
57 dB cooling, 59 heating, with a quiet mode on the remote
Self-drying after use, plus a self-cleaning heat exchanger
The lowest ten-year total of the nine
Right for: Keeping the upfront cost down, or fitting it into a tight space.
Not for: Minimising electricity over the long run, or wanting reviews to read first.
Worth knowing: APF 5.8 and 717 kWh put it in the thirstier group, and heating at 2°C is only 2.8 kW. Released February 2026, with three reviews. No automatic filter cleaning.

Score breakdown — 72/100

Criterion	Stars	Why
Quality	★★☆☆☆	APF 5.8 earns two stars; 2.8 kW at 2°C earns nothing
Value for money	★★★★★	¥49,300 plus ten years at ¥22,227 — ¥271,570, the lowest total here
Easy to live with	★★★★★	59 dB earns four stars, and the 250 mm height earns the fifth
Trust	★★☆☆☆	5.0 from 3 reviews
Only here	★★★★☆	The cheapest unit and the lowest ten-year total, while still offering a quiet mode and self-drying

Nanoe X internal cleaning, and the second-best reviewed here

Panasonic Eolia J series

Panasonic’s standard Eolia for the retail channel
nanoe X is aimed at the smell that develops in a Japanese summer
APF 5.8 and 717 kWh a year

See today’s price on Rakuten→

Why it made the five

Nanoe X internal cleaning after the unit stops
Indoor unit 229 mm deep and 8 kg — slim and light
Built-in wi-fi, controllable from the Eolia app
Hydrophilic-coated heat exchanger and silver-ion antibacterial filter
Right for: Worrying about smells and mould inside the unit, or wanting app control.
Not for: Driving the electricity bill as low as it will go.
Worth knowing: At 717 kWh it is in the thirstiest group — about ¥4,557 a year more than the Hitachi flagship. Heating at 2°C is 2.8 kW, so in a cold region consider a larger capacity.

Score breakdown — 67/100

Criterion	Stars	Why
Quality	★★☆☆☆	APF 5.8 earns two stars; 2.8 kW at 2°C earns nothing
Value for money	★★★★☆	¥60,000 plus ten years at ¥22,227 — ¥282,270 in all
Easy to live with	★★★☆☆	60 dB on the louder measurement; the 290 mm height earns nothing
Trust	★★★☆☆	4.74 across 39 reviews on four sites
Only here	★★★★★	The only model here with nanoe X internal cleaning, in one of the slimmest and lightest indoor units, with the highest review average of the nine

The most-reviewed here, with quiet-mode noise published

Mitsubishi Electric Kirigamine GV series

The standard Kirigamine
Cooling 62/51/41 dB and heating 64/50/43 dB across three settings
APF 5.8 and 717 kWh a year; ten-year total ¥277,570

See today’s price on Rakuten→

Why it made the five

Noise at three fan speeds; quiet mode 41 dB cooling, 43 heating
Indoor unit 225 mm deep and 8 kg, so it barely projects from the wall
42 reviews across Amazon, Yahoo! Shopping and Kakaku.com — the most of the nine
The second-lowest ten-year total
Right for: Keeping the cost down while choosing something other people have actually bought.
Not for: Caring about noise at full fan speed.
Worth knowing: At 62 dB cooling and 64 heating on full fan it is among the louder units here — use the quiet or low setting once the room is cool. The specification sheet mentions no internal cleaning function. Heating at 2°C is 2.8 kW.

Score breakdown — 63/100

Criterion	Stars	Why
Quality	★★☆☆☆	APF 5.8 earns two stars; 2.8 kW at 2°C earns nothing
Value for money	★★★★★	¥55,300 plus ten years at ¥22,227 — ¥277,570 in all
Easy to live with	★★☆☆☆	64 dB at full speed earns two stars, though quiet mode is 41–43 dB
Trust	★★★☆☆	4.58 across 254 reviews on four sites
Only here	★★★★☆	The most reviews of the nine, a 225 mm-deep indoor unit, and — with its sibling — the only published quiet-mode figures

Know before you buy

Every maker measures noise the same way, to JIS C 9612 sound power level, so the decibel figures here are directly comparable.
The efficiency figure is APF. Among these, 5.8 is ordinary and 7.3 is excellent — but the gap between them is only about ¥4,557 a year, while the price gap can be ¥160,000.
Heat pumps lose power as it gets colder, so look at heating output at 2°C outside. These range from 2.8 kW to 4.5.
The quoted noise is the indoor unit at full fan speed. In the quiet mode you would actually sleep with, one model here drops to 34 dB.
The price you see is usually the unit alone. Installation adds roughly ¥26,000 on the one pair we could compare directly, and more if pipes must be extended, covers fitted, an old unit removed or a socket changed.
2026 models launched in February and March, so most have almost no reviews yet. Two of the nine had more than thirty.

How we chose: theme, conditions, scoring

How we chose

Candidates: 58
Met every condition below: 10
Kept: five, each the best at something different

Conditions (all of them, not most of them)

A current model with 2.2 kW cooling capacity, rated for roughly a 6-mat room
APF and annual electricity consumption in kWh are published
Indoor unit noise in dB, to JIS C 9612 sound power level, is published for both cooling and heating
Heating output at 2°C outside is published
Already on sale, with a new unit buyable online

Scoring

Five criteria, one to five stars each, weighted to one hundred points. Every star says where the number came from.

Quality25 pts
- Set by APF: 7.0 or more is five stars, 6.5–6.9 four, 6.0–6.4 three, 5.5–5.9 two, below that one. Add one if heating output at 2°C outside reaches 3.3 kW, one and a half times the rated heating output.
Value for money20 pts
- The cheapest unit-only price on Kakaku.com, plus ten years of electricity at the published annual kWh × ¥31. Under ¥280,000 is five stars, under ¥300,000 four, under ¥330,000 three, under ¥380,000 two, above that one.
Easy to live with20 pts
- Set by the louder of the cooling and heating noise figures: 56 dB or less is five stars, 57–59 four, 60–62 three, 63–64 two, 65 or more one. Add one if the indoor unit is 250 mm tall or less.
Trust15 pts
- Review counts and weighted averages we counted ourselves across Amazon, Yahoo! Shopping and Kakaku.com, alongside Rakuten.
Only here20 pts
- Starts at three stars. Add one or two where a figure or mechanism belongs to this model alone among the nine, and where it bears on running quietly and cheaply in a bedroom.

What we dropped

Candidate	Verdict	Why
Fujitsu General Nocria C series room air conditioner	Runner-up (69/100)	The score is high enough, but its character overlaps with the five
Hitachi Shirokuma-kun X series room air conditioner	Runner-up (67/100)	The score is high enough, but its character overlaps with the five
Toshiba Daiseikai E-C5S series room air conditioner	Runner-up (67/100)	The score is high enough, but its character overlaps with the five
Hitachi Shirokuma-kun E series room air conditioner	Runner-up (59/100)	59 points, below the lowest of the five (63)
Toshiba RAS-DR221C7	Runner-up	APF 7.0, 594 kWh, 56 dB both ways and 4.1 kW of heating at 2°C — an excellent combination, but Kakaku.com marks it as not yet released, so it cannot be bought.
Hitachi RAS-DR2226S	Runner-up	Meets every condition at APF 5.8, but within that group the Mitsubishi GV and Toshiba V-M are cheaper and fill the same role.
Daikin (AN226AES and others)	Outside the theme	APF, annual kWh and low-temperature heating are published, but the retail-channel specification does not give indoor noise in decibels.
Sharp (AY-U22E and others)	Outside the theme	Efficiency figures are published, but the dimensions page has no noise column.
Corona ReLaLa CSH-N2226R	Outside the theme	Efficiency and low-temperature heating are published, but no noise figure appears even in the extended specifications.
Iris Ohyama IPF-2202S	Outside the theme	Publishes 54 dB and APF 5.8, but not annual kilowatt-hours, so running cost cannot be calculated on the same basis.
Hitachi RAS-AJ2226S	Outside the theme	22 Amazon reviews at 4.3 and a bestseller, but it is a trade-channel model with no 2026 specification page we could verify.
Toshiba RAS-U221M	Outside the theme	Full specifications and a good review count, but it is a 2025 model and no longer in Toshiba’s current eight-series range.
Mitsubishi MSZ-X2226, R2226, S2226, GE2226	Outside the theme	Current models, but we took the premium Z and the standard GV to show the range, and left the middle grades out.
Hitachi RAS-WR2226S and RAS-GR2226S	Outside the theme	Current models, but from Hitachi we took the most efficient X series and the E series that meets the 2027 target across its range.

Questions visitors ask

What happens between buying it and using it?

Online you can buy the unit alone or with standard installation. With installation, a fitter contacts you to arrange a date and on the day mounts the indoor unit, runs the pipework through the wall, sets the outdoor unit, vacuums the lines and tests it. Extra charges typically arise for longer pipe runs, wall-mounting or stacking the outdoor unit, decorative pipe covers, removing and recycling an old unit, changing a socket or adding a circuit, and drilling a new hole. On the one machine where we could compare directly, the Hitachi RAS-ER2226S, the unit alone was ¥137,000 and the cheapest with standard installation ¥162,800 — a difference of about ¥26,000.

Which costs least to run?

Hitachi’s RAS-XR2226S at 570 kWh a year, about ¥17,670 at ¥31 a kilowatt-hour. Then Mitsubishi’s MSZ-ZW2226 at 603, and three machines at 630. The thirstiest are four models at 717 kWh, about ¥22,227. The widest gap is ¥4,557 a year, or about ¥46,000 over ten years — while the spread in purchase price across these nine is ¥160,000. Efficiency alone rarely repays a flagship.

How quiet is a given decibel figure in practice?

The numbers here are JIS sound power levels measured in an anechoic chamber at the highest fan speed — not what you hear at night. Mitsubishi publishes the full range: its Z series runs 58/50/45/34 dB cooling, so the quiet mode is 34. Its GV series gives 62/51/41. Comparing only at full speed, Fujitsu General’s 55 dB on both cooling and heating is the lowest here.

Will it actually heat the room in winter?

A heat pump loses output as the outside temperature falls, so the figure to look at is heating output at 2°C. Hitachi’s RAS-XR2226S manages 4.5 kW and Mitsubishi’s MSZ-ZW2226 4.1 — roughly twice their rated output. Most of the others are 2.8 to 3.1 kW. In Kanto or further west, 2.8 kW is fine for six mats; further north, or if you want the room warm quickly in the morning, 4 kW tells.

Why aren’t Daikin, Sharp and Corona here?

Because we required published indoor noise in decibels. Daikin’s retail-channel specifications do not list it, nor do Sharp’s dimension pages or Corona’s extended specifications. Iris Ohyama publishes noise and APF but not annual kilowatt-hours, so we could not calculate running cost on the same basis. This is about what is published, not about the machines.

Why do 2026 models have so few reviews?

Most 6-mat models for 2026 launched in February and March, so across Kakaku.com, Amazon and Yahoo! Shopping several have single-figure review counts. Only two of our nine passed thirty: the Mitsubishi GV at 42 and the Panasonic at 32. If reviews matter to you, those two — or a 2025 model still in stock — are the pragmatic choice.

Changes

2026-10-25　First published. Scored from 58 candidates.