Is a wall-mounted heat pump quiet enough for a bedroom?

Yes, if the model is well chosen. In quiet mode, 25 of the 32 wall units in our catalogue (12,000 BTU, R-32 or R-454B) go down to 25 dB or less, below the 30 dB guideline the WHO recommends for a bedroom. At night, turn on quiet mode or the lowest fan speed.

What is the quietest wall-mounted heat pump?

In our catalogue of 12,000 BTU R-32 or R-454B wall units, the quietest in quiet mode is the MIDEA25 (18 dB). Outdoors, it's the Samsung WindFree and the Lennox MWHD (46 dB at 1 m). No model is the quietest everywhere: choose based on the room and on the neighbour.

Why is the outdoor unit louder in winter?

In extreme cold, it works harder to draw heat from the outdoor air, and it defrosts regularly. Manufacturers' spec sheets give a value under rated conditions: the unit may be more audible in very cold weather.

What is the noise limit for a heat pump in Montreal?

It depends on the borough. For example: 50 dB at the property line in Ahuntsic-Cartierville, Lachine, Montréal-Nord and Saint-Léonard; 55 dB by day and 52 dB at night in Mercier–Hochelaga-Maisonneuve (montreal.ca, August 3, 2026). In Longueuil, 53 dB(A) in Saint-Hubert, Greenfield Park and Vieux-Longueuil.

Does a fence really reduce the noise at the neighbour's?

Yes, if it blocks the line of sight between the unit and the neighbour. The AHRI 275 standard gives a 4 to 17 dB reduction depending on the detour the sound has to make. Keep the manufacturer's clearances so air can circulate.

Do two heat pumps make twice as much noise?

No. Two identical units add 3 dB: the sound energy doubles, but the number goes, for example, from 52 to 55 dB, not to 104 dB.

What does dB(A) mean?

It's an A-weighted decibel: the measurement follows the sensitivity of the human ear, which hears low-pitched sounds less well. It's the unit used on spec sheets and in municipal bylaws.

Is the spec sheet figure what I'll hear at home?

It's a laboratory measurement. At your home, walls, distance and ambient noise change the result, and the actual level may be higher. Compare models using figures of the same kind: sound pressure with sound pressure.

Is the simulator's method reliable?

It follows the AHRI 275 standard, used by the industry to estimate the noise of an outdoor unit at a given point. It does not account for wind, temperature or ambient noise, and it assumes the spec sheet gives the sound pressure at 1 m. It is an estimate: only an on-site measurement is conclusive.

My unit is making an unusual noise. What should I do?

Clear the outdoor unit, turn the unit off, switch off the breaker for 15 to 20 minutes, then turn it back on. If the noise comes back, call us: we run remote checks before sending a technician.

2026 Guide · verified data

Important information · Wall-mounted heat pumps

By AirGreen Climatisation & ChauffagePublished April 11, 2023Updated September 24, 202610 min read

Are Wall-Mounted Mini Split Heat Pumps Noisy? 2026 Guide

Considering a wall-mounted heat pump, but wondering if it'll be too noisy? You're not alone. This guide answers with real figures: the 32 wall units of 12,000 BTU in our catalogue, the Government of Québec and WHO benchmarks, and the industry method (AHRI 275) for calculating what your neighbour will hear.

Calculate the noise at your neighbour's See the quietest

The catalogue sound meter32 wall units, R-32 and R-454B

21.5dB

Median, indoor unit in quiet modeFrom 18 to 32 dB depending on the modelBelow the 30 dB guideline the WHO recommends for a bedroom.

25 of 32wall units at 25 dB or less in quiet mode

20 dBa whisper heard at 1 m (Québec)

−6 dBevery time the distance doubles (AHRI 275)

50 dBproperty-line limit in 4 Montreal boroughs

In short

Based on our 32 spec sheets (R-32, R-454B), as of September 24, 2026

The short answerNo, if the model and the location are well chosen.

In the room18 to 32 dB in quiet mode, about the level of a whisper; 38 to 49 dB at full speed.

Outdoors46 to 57 dB at 1 m from the outdoor unit. The level drops by about 6 dB every time the distance doubles.

At the neighbour'sThe limit is often 50 dB at the property line in Montreal, and 53 dB in three areas of Longueuil.

01 · What is a mini split?

What is a wall-mounted mini split heat pump?

A wall-mounted heat pump heats and cools room by room, without air ducts. Tap a number on the diagram to see each part and the noise it makes.

A wall-mounted heat pump is a zoned heating and cooling system: each room or space gets its own unit. Unlike central HVAC systems, which distribute air through ducts, a mini split puts its units directly in the rooms it serves.

It consists of an outdoor unit and one or more indoor units, connected by a small conduit that holds the refrigerant lines, the power cable and the condensate drain.

Modern wall-mounted mini split heat pump with colourful patterns – AirGreen 2026 noise guide — A well-chosen wall-mounted heat pump fades into the background.

Mini split or central system: the difference in brief
	Wall-mounted mini split	Central system
Where the air goes	Directly into the room, through the wall unit	Through air ducts, to each room
Controls	Room by room, one remote per unit	Usually one thermostat for the whole house
Installation	A small conduit through the wall	A network of ducts in walls and ceilings
What you hear	The fan, in the room; the compressor, outdoors	Airflow at the vents; the compressor, outdoors

The indoor unit

Mounted on the wall of the room, it blows warm or cool air. Its fan makes the noise you hear in the room.

What you hearA gentle whoosh. On our spec sheets: 18 to 32 dB in quiet mode, 38 to 49 dB at full speed.

02 · How many decibels?

How many decibels does a wall-mounted heat pump make?

The short answer: in quiet mode, most go down to the level of a whisper. At full speed, they stay below a normal conversation. Tap a benchmark to compare.

Our wall units

21.5dB

Wall unit, quiet mode

Median of our 32 wall units: from 18 to 32 dB depending on the model. About the level of a whisper.

Source: airgreen.ca spec sheets

Compare with another benchmarkComparison benchmark

Wall unit, quiet mode (21.5 dB) carries 71 times less sound energy than a library (40 dB).

Sound energy, calculated on the logarithmic scale: 10 dB more = 10 times more energy.

The 3 dB ruleHow many identical outdoor units, side by side?

55 dB+3 dB

For a 52 dB unit at 1 m. Two identical units add 3 dB: the energy doubles, the number doesn't (CCOHS).

Benchmarks: Government of Québec, “Mesure du bruit” (June 16, 2022), and WHO (1999). Our wall units: levels declared by the manufacturers on our 32 spec sheets.

03 · What causes the noise

What causes the noise in a wall-mounted heat pump?

Three factors make the difference: the outdoor unit, the location and the type of indoor unit.

Outdoor unit noise

It houses the compressor and the fan. On our spec sheets, it shows 46 to 57 dB at 1 m (median 52 dB): less than a normal conversation (60 dB). The level drops quickly with distance.

The location

Outdoors, every wall within 3 m reflects sound: +3 dB against one wall, +6 dB in a corner (AHRI 275). Indoors, hard surfaces make a sound seem louder than in a furnished room (CCOHS). Respect the manufacturer's clearances around the indoor unit.

The type of indoor unit

Wall-mounted, ceiling cassette or floor console: the figures differ mostly in quiet mode. Compare them in the chart below.

Wall-mounted, cassette or console: which is the quietest?

1520304050 dB

Wall-mounted32 models18 to 32 dBmedian 21.5 dB

Ceiling cassette8 models22 to 32 dBmedian 25 dB

Floor console5 models24 to 29.5 dBmedian 27 dB

In quiet mode, wall units go the lowest: a median of 21.5 dB, compared with 25 dB for cassettes and 27 dB for consoles.

Indoor sound levels, 12,000 BTU R-32 or R-454B models in our catalogue
Type	Models	Quiet	Full speed
Wall-mounted	32	18 to 32 dB	38 to 49 dB
Cassette	8	22 to 32 dB	34 to 46 dB
Console	5	24 to 29.5 dB	42 to 45 dB

03 · Summer, winter, night

The same unit doesn't make the same noise in July and in January.

An inverter heat pump adjusts its speed to demand. Choose a scenario: see where it sits between the minimum and maximum on its spec sheet.

Night, quiet mode

The fan runs at its lowest speed and the compressor slows down as soon as the bedroom reaches the right temperature. It's the setting to use for sleeping.

What you might hear

Slight hiss or sound of flowing water The unit keeps running after reaching the set point

Indoor unitnear minimum

Spec sheet minimumSpec sheet maximum

Outdoor unitlow

Spec sheet minimumSpec sheet maximum

Illustration. The actual position depends on the model, the house and the set point. Each model's dB figures are on its spec sheet.

04 · The ranking

Which wall-mounted heat pumps are the quietest?

At night, look at quiet mode. For the neighbour, look at the diamond: the outdoor unit. Add up to 3 models to the comparison.

Sort by

Filter

32 models

Indoor unit, from quiet mode to full speedOutdoor unit, at 1 m

1Midea MIDEA25R-454BHeats down to −25 °C

18Quiet46Max56Outdoors

View product

2Fujitsu ALTAIR 500 (KPAS)R-32Heats down to −15 °C

19Quiet42Max48Outdoors

View product

3Fujitsu ALTAIR 700 (KMAS)R-32Heats down to −15 °C

19Quiet42Max50Outdoors

View product

4Gree Extreme R32R-32Heats down to −30 °C

19Quiet43Max55Outdoors

View product

5WILLIS ULTIMA R32R-32Heats down to −30 °C

19Quiet43Max56Outdoors

View product

6Midea MIDEA35R-454BHeats down to −30 °C

19Quiet42Max57Outdoors

View product

7CanAir 4C28R-454BHeats down to −30 °C

19.5Quiet47Max56Outdoors

View product

8Gree Vireo R32R-32Heats down to −30 °C

20Quiet43Max52Outdoors

View product

Comparison3 of 3

Tap “Compare” on up to 3 models. The best figure in each row is highlighted.

Fujitsu ALTAIR 500 (KPAS)Spec sheet

Samsung WindFree MaxHeatSpec sheet

Sharp CHUSpec sheet

Quiet mode

19 dB22 dB22 dB

Full speed

42 dB39 dB44 dB

Outdoors, at 1 m

48 dB46 dB50 dB

At the neighbour's, 3 m, in a corner

44 dB42 dB46 dB

Heats down to

−15 °C−30 °C−30 °C

Refrigerant

R-32R-32R-32

“At the neighbour's”: estimate based on the AHRI 275 standard (corner +6 dB, 3 m −9.5 dB).

Values declared by the manufacturers, as listed on our spec sheets on September 24, 2026. One row per series; 115 V versions and colours are grouped.

Shop by brand

Sharp, Gree and Haxxair remain among our most requested brands. Compare their models with the figures above before you choose.

Sharp Gree Haxxair All wall-mounted heat pumps

05 · Indoors or outdoors

Quiet in the bedroom, quiet for the neighbour?

Each dot is one model (or several, when their figures are identical). Bottom left: quiet indoors and outdoors.

Outdoors, at 1 m (dB)

Quiet indoors and outdoors

161820222426283032344446485052545658

Indoor, quiet mode (dB)

Selected point

22dB indoors, quiet

46dB outdoors, at 1 m

Quiet indoors and outdoors

Samsung WindFree MaxHeatR-32 · full speed 39 dBSpec sheet

Samsung WindFree StandardR-32 · full speed 39 dBSpec sheet

Lennox MWHDR-32 · full speed 39 dBSpec sheet

The quietest indoors isn't the quietest outdoors

The MIDEA25 goes down to 18 dB in quiet mode, but its outdoor unit shows 56 dB at 1 m.

Quietest outdoors

Samsung WindFree (MaxHeat and Standard) and Lennox MWHD: 46 dB at 1 m, and 22 dB indoors in quiet mode.

The rule

Noise-sensitive bedroom: check the quiet-mode figure. Close neighbour: check the outdoor unit, then the location.

06 · The neighbour simulator

Will your neighbour really hear your heat pump?

Set the six steps: the result, the line-by-line calculation, the plan and the curve update. AHRI 275 method.

At the line≈ 46 dBUnder the limit · 4 dB to spare

1The model

Outdoors: 50 dB at 1 mIndoors: 22 to 44 dBView product

2Distance to the property line

Distance3 m

1 m5 m10 m15 m

In Montreal, 1 to 3 m minimum depending on the borough; in Longueuil, 1 m. Check your city's rule.

3The walls around the unit

4A barrier between the unit and the neighbour?

The detour is the extra distance sound has to travel to get around the barrier. The taller the barrier and the closer it is to the unit, the bigger the detour.

5Your city and the time of day

6What about the neighbour's bedroom?

Their window is … from the line2 m

0 m5 m10 m

3 m

Level by distance

46 dB at 3 mLimit: 50 dB

Every time the distance doubles, the level drops by about 6 dB.

At the property line

≈ 46dB

Under the limit · 4 dB to spare

30 dBLimit: 50 dB · Ahuntsic-Cartierville70 dB

Manufacturer's spec sheet, at 1 m50 dB

Walls: in a corner+6 dB

Distance: 3 m−9.5 dB

Barrier: none0 dB

Total, rounded46 dB

In the neighbour's bedroom

≈ 19 dBBelow the WHO 30 dB guideline

At 5 m from the unit, with the window closed, double glazing (−23 dB).

Indicative estimate based on the AHRI 275 standard, using the sound pressure on the spec sheet. Wind, snow and ambient noise change the real result. In extreme cold, the unit may work harder than under the spec sheet conditions. Limit source: montreal.ca, updated August 3, 2026.

Have an estimator confirm it

06 · Six levers

Six ways to cut decibels, with numbers.

You can test the first four in the simulator. The last two are settled at installation.

−6 dBDouble the distance

Going from 2 to 4 m from the line takes off about 6 dB. Each doubling gives the same gain.

Double the distance

−6 dBMove out of the corner

Two nearby walls reflect sound. Against a single wall, you gain 3 dB; in the open, 6 dB.

Move the unit into the open

−4 to −17A barrier that hides the unit

Solid fence, low wall or house corner: it must block the line of sight between the unit and the neighbour. Keep the manufacturer's clearances.

Add a solid fence

11 dBA quieter model outdoors

In our catalogue, the outdoor unit ranges from 46 to 57 dB at 1 m depending on the model.

Try the quietest

BaseIsolate vibrations

A solid base, anti-vibration pads, no rigid contact between the lines and the house, and a wall penetration sealed with a flexible material.

SizeDon't oversize

An oversized unit starts and stops often. These short cycles are more disruptive than slow, continuous operation.

07 · Limits by city

What is the heat pump noise limit in your city?

The numeric limits we verified as of September 24, 2026. Each card leads to our detailed page for that city.

Verified

Ahuntsic-Cartierville50 dBAt the property line

Never more than 50 dB at the property line.