Which air conditioner should you choose in Luxembourg, and what does it cost?
2026 guide: system, sizing, budget, rules
In Luxembourg, the right system depends on what your home allows. An installed reversible split (air-to-air heat pump) costs €2,600 to €4,550 including VAT for one room and €9,650 to €25,000 for a ducted system serving a whole house; where no outdoor unit is allowed, a monoblock costs €1,700 to €2,950 (renov.lu survey, September 2026). No air conditioner qualifies for the Klimabonus or the 3% VAT rate.
- Installed price (including 17% VAT, renov.lu survey, September 2026): single split €2,600 to €4,550, dual split €4,900 to €7,600, tri-split €6,450 to €10,100, ducted €9,650 to €25,000; portable unit €200 to €1,200, no installation.
- Sizing: 60 to 120 W of cooling per m² depending on insulation, i.e. about 2.5 kW for a moderately insulated 25 m² room.
- Electricity: about €30 per summer for that room (4 hours a day for 70 days, SEER 6), at the average price of €0.258/kWh including VAT estimated by the government for 2026.
- Grants: none, neither Klimabonus nor 3% VAT (the housing VAT scheme excludes air-conditioning systems).
- Permits: municipal building regulations for the outdoor unit; in a co-ownership building, a general meeting vote by a majority of all co-owners’ votes (Law of 16 May 1975, Article 16).
- Installation and refrigerant: reserved for an F-gas certified company; from 1 January 2029, no new air-to-air split of up to 12 kW running on R32 may be placed on the market.
Which system suits your home, and at what price?
The simulator estimates in 2 minutes the capacity and budget based on floor area, insulation and number of rooms; you can then receive 3 quotes from verified installers.
Which air conditioner is right for your home?
In Luxembourg, three questions are enough to find the right system: can you install an outdoor unit (municipality, co-ownership, landlord), how many rooms need cooling, and do you also want to heat with it? Installed budgets including VAT, renov.lu survey of September 2026.
| Your situation | Recommended system | Installed budget incl. VAT |
|---|---|---|
| One room (bedroom, living room), outdoor unit possible | Reversible single split | €2,600 to €4,550 |
| Flat, 2 or 3 rooms to cool, balcony or facade allowed | Dual or tri-split, with a single outdoor unit | €4,900 to €7,600 (2 rooms); €6,450 to €10,100 (3 rooms) |
| House, 4 or 5 rooms | Multi-split | up to about €12,500 |
| New build or major renovation, attic or false ceilings available | Ducted system | €9,650 to €25,000 |
| Outdoor unit refused (protected facade, co-ownership) | Fixed monoblock without outdoor unit | €1,700 to €2,950 |
| Tenant without consent, or a few days of use a year | Portable air conditioner | €200 to €1,200, no installation |
| House heated with oil or gas, boiler to replace | Air-to-water heat pump for heating, AC as a complement if needed | €12,000 to €24,000 (3% VAT), Klimabonus available |
A poorly insulated house needs up to 120 W of cooling per m², a recent home 60 to 70 W. Roof insulation, which the Klimabonus subsidises, reduces the capacity you need and therefore the price of the unit.
The 5 types of air conditioning, from portable to ducted
A fixed air conditioning system almost always pairs an outdoor unit, which rejects the heat, with one or more indoor units connected by refrigerant pipes: this is the « split ». Without an outdoor unit (monoblock, portable), installation is simpler, but the appliance is less efficient and noisier in the room.
| Type | How it works | Impact on the facade | Heats in winter? | Best for |
|---|---|---|---|---|
| Portable air conditioner | Unit on wheels, hot air expelled through a hose at the window | None | Some models, as back-up | Tenants, occasional use |
| Fixed monoblock without outdoor unit | Single wall unit that draws and expels air through two holes | Two core holes of 160 to 200 mm | Yes, as back-up | Facades where an outdoor unit is refused |
| Single split | 1 outdoor unit connected to 1 indoor unit | Outdoor unit and one pipe passage | Yes (reversible) | One room, a studio |
| Multi-split (dual, tri, 4 to 5 rooms) | 1 outdoor unit connected to 2 to 5 indoor units | Outdoor unit and one passage per room | Yes (reversible) | Flats, houses |
| Ducted | Unit hidden in the attic or a false ceiling, air blown through grilles | Outdoor unit | Yes (reversible) | New or extensively renovated houses |
Portable unit: no drilling, no installer, no permit, but a single room and three to four times more electricity than a split (portable air conditioner price and limits). Monoblock without outdoor unit: more visible and noisier than a split, and it still goes through the facade, so a co-ownership vote is required (air conditioning without an outdoor unit). Single split, multi-split, ducted: the first is the most efficient for one room, the second avoids lining up outdoor units, the third leaves only grilles visible but needs space for ducts (single split, multi-split or ducted).
« Reversible » means air-to-air heat pump: almost every split sold in 2026 also heats, because its cycle reverses in winter. Reversible air conditioning and air-to-air heat pump describe the same appliance.
Reversible air conditioning (air-to-air heat pump) or air-to-water heat pump?
A reversible air conditioner is an air-to-air heat pump: it blows warm or cool air into the room. An air-to-water heat pump heats the water in radiators or underfloor heating, plus domestic hot water: it is a central heating system, not air conditioning. In Luxembourg, only the second one qualifies for grants.
| Criterion | Reversible AC (air-to-air) | Air-to-water heat pump |
|---|---|---|
| Role | Cooling, back-up or mid-season heating | Central heating and domestic hot water |
| Distribution | Air blown by wall units or grilles | Radiators, underfloor heating |
| Summer cooling | Yes, its primary function | Gentle cooling through the floor on some reversible models |
| Installed price incl. VAT | €2,600 to €4,550 (1 room); €9,650 to €25,000 (ducted) | €12,000 to €24,000 (existing house, 3% VAT) |
| Klimabonus | None | €10,000 when replacing fossil-fuel or electric heating in a house; €12,000 if ordered between 1 January 2026 and 30 June 2027 |
| VAT | 17% | 3% in a main residence at least 10 years old |
| Mandatory inspection | No | Yes (Law of 17 August 2026): first inspection 1 to 2 years after commissioning, then every 4 years |
To replace a boiler, the air-to-water heat pump is the only one of the two that receives the Klimabonus: see the cost of a heat pump in Luxembourg. To cool a few rooms and heat in spring and autumn without touching the central heating, a reversible AC is enough: with a seasonal heating efficiency (SCOP) of 4, each kWh of heat costs about €0.065 of electricity, four times less than with an electric convector heater. More on this dual use in our reversible air conditioning guide.
How does air conditioning work?
An air conditioner does not make cold: it moves heat from inside to outside using a refrigerant that circulates in a closed loop between the two units. With an efficiency of 3, every kWh of electricity removes 3 kWh of heat. The cycle has four stages.
| Stage | Component | What happens |
|---|---|---|
| 1. Evaporation | Evaporator (indoor unit) | The cold refrigerant absorbs heat from the room and vaporises; the air blown out is cooled and dehumidified |
| 2. Compression | Compressor (outdoor unit) | It compresses the gas, which heats up; this is where most of the electricity goes |
| 3. Condensation | Condenser (outdoor unit) | The refrigerant releases its heat to the outside air and turns back into liquid |
| 4. Expansion | Expansion valve | Pressure drops, the refrigerant cools and flows back to the indoor unit |
Two figures on the product sheet sum up efficiency: SEER, the seasonal cooling efficiency, and SCOP, the seasonal heating efficiency. On the EU energy label, class A++ means a SEER of at least 6.1 and class A+++ a SEER of at least 8.5. « Inverter » models, now the norm, modulate the compressor speed: they use less electricity and make less noise. In heating mode, a valve reverses the cycle and the outdoor unit extracts heat from the air, even below freezing.
What capacity do you need? kW per m² rules of thumb
Allow 60 to 120 W of cooling per m² depending on insulation, i.e. about 2.5 kW for a moderately insulated 25 m² bedroom. Capacity is worked out room by room, then rounded up to the next standard size: 2.0 – 2.5 – 3.5 – 5.0 – 7.0 kW.
| Home | Rule of thumb | 20 m² room | 35 m² room |
|---|---|---|---|
| Recent, well insulated | 60 to 70 W/m² | 1.2 to 1.4 kW, i.e. a 2.0 kW unit | 2.1 to 2.5 kW, i.e. 2.5 kW |
| Average insulation | 80 to 100 W/m² | 1.6 to 2.0 kW, i.e. 2.0 kW | 2.8 to 3.5 kW, i.e. 3.5 kW |
| Poorly insulated, under the roof, large south-facing glazing | 100 to 120 W/m² | 2.0 to 2.4 kW, i.e. 2.5 kW | 3.5 to 4.2 kW, i.e. 5.0 kW |
Add 10 to 20% for a heavily glazed room facing south or west, and 10 to 15% for a 3 m ceiling. Oversized, the unit short-cycles and dehumidifies poorly; undersized, it runs non-stop without reaching the set temperature. Full method, including BTU conversion: how to size your air conditioning.
Budget: how much does installed air conditioning cost in Luxembourg?
In Luxembourg, installed air conditioning costs €2,600 to €4,550 including VAT for one room with a single split and up to €25,000 for a house with a ducted system. These ranges cover the unit, installation and commissioning, with 17% VAT: air conditioning qualifies neither for the 3% rate nor for the Klimabonus.
| System | Typical use | Installed price (incl. 17% VAT) |
|---|---|---|
| Portable air conditioner | 1 room, no installation | €200 to €1,200 |
| Fixed monoblock without outdoor unit | 1 room | €1,700 to €2,950 |
| Reversible single split Most common | 1 room | €2,600 to €4,550 |
| Dual split | 2 rooms | €4,900 to €7,600 |
| Tri-split | 3 rooms | €6,450 to €10,100 |
| Multi-split, 4 to 5 rooms | A whole floor or dwelling | up to about €12,500 |
| Ducted system | Whole house | €9,650 to €25,000 |
renov.lu survey, September 2026: prices including 17% VAT provided by partner installers in Luxembourg, for a standard installation.
The price mainly depends on the brand and energy class, the length of the pipe run between units, access to the facade or roof, and whether a dedicated electrical circuit is needed. The item-by-item breakdown, extra costs and worked examples are on our page on air conditioning installation cost in Luxembourg.
An 85 m² flat in Luxembourg City, living room and two bedrooms to cool, balcony approved by the co-owners: a reversible tri-split costs €6,450 to €10,100 installed including VAT, with no grant, and about €90 of electricity per summer.
What does air conditioning cost to run?
Cooling a 25 m² room all summer costs about €30 of electricity with a recent split, at the average price of €0.258/kWh including VAT estimated by the government for a typical household in 2026, state support included (gouvernement.lu). The calculation: cooling capacity ÷ SEER × hours of use × price per kWh.
| Equipment (4 hours a day, 70 days) | Cooling capacity | Electricity per summer | Cost at €0.258/kWh |
|---|---|---|---|
| 25 m² bedroom, single split, SEER 6 | 2.5 kW | about 117 kWh | about €30 |
| 35 m² living room, single split, SEER 6 | 3.5 kW | about 163 kWh | about €42 |
| 80 m² flat, tri-split, SEER 6 | 7.5 kW | about 350 kWh | about €90 |
| 150 m² house, ducted, SEER 6 | 12 kW | about 560 kWh | about €145 |
| Portable unit, real efficiency 1.5 to 2.2 | 2.5 kW | about 320 to 470 kWh | about €80 to €120 |
These figures assume the unit runs at full capacity for 4 hours a day: they are a ceiling, as an inverter often works at part load. A higher energy class saves little in cooling mode: for the 35 m² living room, moving from a SEER of 6.1 (A++) to 8.5 (A+++) saves about €12 per summer. Heating efficiency (SCOP) matters more if you use the unit for heating in spring and autumn. The surest savings: set 25 to 26 °C rather than 20 °C, close the shutters during the day and clean the filters. Detailed method and other cases: air conditioner electricity consumption.
Rules in Luxembourg: grants, municipality, co-ownership, noise
In Luxembourg, air conditioning is not subsidised, is charged at 17% VAT, and its outdoor unit depends on your municipality’s regulations; in a co-ownership building, you also need a vote of the general meeting. To air-condition offices or a shop, see how to finance works and energy for a business.
No grants, 17% VAT
Air-to-air heat pumps are not on the list of installations supported by the Klimabonus Wunnen (Law of 24 July 2026): only air-to-water and ground-source heat pumps are. The official housing VAT list expressly excludes « air-conditioning systems and wellness devices » (guichet.lu): an installer who promises 3% should be able to show written approval from the AED, the VAT authority. See also which works qualify for 3% VAT.
Municipal permit
The mayor (bourgmestre) authorises the works under the general development plan (PAG), the local development plan (PAP) and the municipality’s building regulations. The model regulation (circular no. 2023-119) requires technical equipment to fit within the building envelope and does not exempt outdoor units: on a street-facing facade or in a protected area, a permit is likely. Ask the municipal technical department before ordering. Procedure and timescales: permit for an outdoor unit on the facade.
Co-ownership: general meeting vote
An outdoor unit, a hole through the facade or equipment fixed to a common part affects the common parts or the external appearance of the building: you need approval from the general meeting, voted by a majority of all co-owners’ votes (amended Law of 16 May 1975, Article 16(b); Legilux). This also applies to a monoblock, which requires two core holes. Procedure and appeals: air conditioning in co-ownership buildings.
Noise: 40 dB(A) at the neighbouring plot
The model building regulation limits noise from outdoor equipment to 40 dB(A) (average level over one hour) at the boundary of the nearest neighbouring building plot; the level is increased by 5 dB for tonal or impulsive noise, and the official schallrechner.lu calculator lets you check a location. This limit only applies if your municipality has adopted the model text; otherwise its own regulation and the local police regulation on neighbourhood noise apply. See: air conditioning noise and neighbourhood rules.
Tenants: landlord’s consent first
A tenant must obtain the landlord’s written consent before drilling a wall or installing an outdoor unit; in a co-ownership building, it is the landlord who requests the vote. Without consent, only a portable unit, whose hose goes out of a window without fixing anything, remains possible.
Why an F-gas certified installer is mandatory
In Luxembourg, only a company certified for fluorinated gases by the Environment Agency (Law of 22 June 2016) may connect, commission or recharge the refrigerant circuit of a split system (environnement.public.lu). EU rules go further: a split system, whose circuit is not sealed in the factory, may only be sold to a private buyer if it is established that a certified company will install it.
Before signing, ask for the company’s certificate, a technical visit with a room-by-room capacity calculation, a quote stating the pipe length included, then the commissioning report (vacuum test, leak test). Portable units and monoblocks are sealed in the factory and need no work on the refrigerant. To compare offers: choosing an air conditioning installer and the steps of an installation.
R32, R290: what the 1 January 2029 deadline changes
From 1 January 2029, air-to-air split systems of up to 12 kW containing a refrigerant with a global warming potential (GWP) of 150 or more may no longer be placed on the market in the European Union (Regulation (EU) 2024/573, Annex IV). R32 (GWP 675), the refrigerant in most splits sold in 2026, is affected; R290 (propane, GWP 3) is not.
| Deadline | New equipment concerned | Consequence |
|---|---|---|
| Since 1 January 2025 | Splits with less than 3 kg of refrigerant, GWP of 750 or more | R410A (GWP 2,088) has disappeared from new splits |
| 1 January 2027 | Monoblocks of up to 12 kW, GWP of 150 or more | Monoblocks without outdoor unit switch to R290 (all F-gases banned in 2032) |
| 1 January 2029 | Air-to-air splits of up to 12 kW, GWP of 150 or more | End of new R32 splits |
| 1 January 2035 | Splits of up to 12 kW, any F-gas | Natural refrigerants only |
These dates ban the sale of new equipment, not the use of units already installed: an R32 split installed in 2026 can keep running. R290 is flammable: the unit must respect the minimum room size stated by the manufacturer.
Air conditioning maintenance and lifespan
No annual maintenance is required for a residential split in Luxembourg: the leak check under EU rules only applies from 5 tonnes CO₂ equivalent of refrigerant, about 7.4 kg of R32, far above the charge of a domestic unit. The Law of 17 August 2026 on heat pump inspections only covers heat pumps connected to a water circuit, not air-to-air units.
Maintenance is still worthwhile: clean the indoor unit filters every two to four weeks in season, keep the outdoor unit clear, and have a professional check the circuit every one to two years, for about €100 to €150 (single split) or €200 to €350 (multi-split). Well maintained, a split usually lasts 12 to 20 years, a portable unit 5 to 8 years. Schedule and tips: air conditioning maintenance and cleaning; signs of wear and repairs: lifespan and breakdowns.
Heatwave: what to do if you are not yet equipped?
In the middle of a heatwave, installers are overbooked and a split requires a visit, sometimes a permit and a vote: a portable unit (€200 to €1,200) is then the only immediate solution, for one room. Better to plan ahead and have a reversible split installed in autumn or winter.
- Close shutters and blinds on the sunny side from the morning; ventilate at night when the outside air is cooler.
- Cool the bedrooms of elderly people, babies and people with chronic illness first, as they are the most vulnerable to heat.
- Follow MeteoLux weather warnings to anticipate peaks.
Solutions without air conditioning and advice by profile: what to do in a heatwave in Luxembourg and keeping your house cool in summer.
Choosing and sizing
Cost, installation and permits
Estimate your air conditioning and compare quotes
The air conditioning simulator estimates in 2 minutes the capacity and installed price for your home; the air conditioning quote request then passes your project to F-gas certified installers, who contact you within 48 hours to arrange a technical visit. Free and without commitment. If the installation needs other work, such as a dedicated electrical circuit or a suspended ceiling, find a verified tradesperson by trade.
Have your air conditioning installed before summer 2027
Autumn and winter leave time to obtain the municipality’s or co-owners’ approval, and a reversible split can heat from this winter.
Frequently asked questions about choosing air conditioning in Luxembourg
Which air conditioner should I install in a flat in Luxembourg?
A single split (€2,600 to €4,550 including VAT) or a dual split (€4,900 to €7,600) if the general meeting approves an outdoor unit: it is the most efficient and quietest option. Otherwise, a fixed monoblock (€1,700 to €2,950) does without one, but it needs two holes in the facade, which also requires a vote. If nothing can be drilled, a portable unit (€200 to €1,200) remains.
Which air conditioning should I choose for a whole house, and on what budget?
A multi-split, which connects a single outdoor unit to one unit per room: €6,450 to €10,100 including VAT for 3 rooms, up to about €12,500 for 4 to 5 rooms. With an accessible attic or false ceilings, a ducted system (€9,650 to €25,000) hides the units and serves every room. If the oil or gas boiler also needs replacing, look first at an air-to-water heat pump, the only one supported by the Klimabonus.
I am a tenant: can I have air conditioning installed?
Yes for a portable unit, which does not alter the property: its hose goes out of a window without drilling or fixing. For a split or a fixed monoblock, you need the landlord’s written consent before any drilling and, in a co-ownership building, a general meeting vote that the landlord must request. Agree in writing who pays for installation and maintenance, and whether the unit stays in the property when the lease ends.
Will an R32 air conditioner bought in 2026 be banned in 2029?
No. From 1 January 2029, Regulation (EU) 2024/573 bans placing on the market new air-to-air splits of up to 12 kW containing a refrigerant with a GWP of 150 or more, such as R32. It does not ban the use of equipment already installed: an R32 split fitted in 2026 can keep running. New models will switch to R290 (propane).
Can I buy a split system online and install it myself?
You can fix the brackets and prepare the openings, but you may not connect or commission the refrigerant circuit: in Luxembourg, this step is reserved for an F-gas certified company. The seller of a split system must also make sure it will be installed by a certified company. Before buying, check that an installer is willing to connect and guarantee a unit they did not supply.
What temperature should I set the air conditioning to during a heatwave?
Set 25 to 26 °C in living areas, even when it is over 30 °C outside: the air blown out is also dehumidified, which is enough to feel comfortable. Going down to 20 °C uses much more electricity and causes a thermal shock when you step outside. At night, sleep mode raises the set point gradually; angle the louvres so the air does not blow directly onto the bed.
When is the best time to have air conditioning installed in Luxembourg?
Autumn and winter. Installers are more available than in spring, you have time to obtain the municipality’s approval or the co-owners’ vote, and a reversible split installed in October immediately serves as back-up heating. Request your quotes by early in the year at the latest to be equipped before the first hot days.