Air to Air Heat Pump Ireland: Cost, Grant and Summer Cooling

Last updated: November 2026
An air to air heat pump is the same machine as a wall-mounted split air conditioner. One unit goes on the inside wall, one goes outside, and two pipes join them. It heats a room in winter and cools it in summer. One room costs about €2,000-3,500 fully fitted. SEAI pays up to €9,500, but only when it replaces your heating. It does not heat water.

⚡ Quick Summary

🌿 Price fitted: about €2,000-3,500 for one room and €4,000-6,500 for two rooms on one outdoor unit (Irish installer prices, November 2026).
🌿 Grant: SEAI lists air to air at up to €9,500 for houses and apartments. The home must be built and occupied before 2021, and the heat pump must replace your current heating.
🌿 Heating cost: a 2.5 kW unit gives 3.2 kW of heat for about 21c an hour at 35c/kWh. A 2 kW plug-in heater costs 70c an hour.
🌿 Cooling cost: about 17-22c an hour at full power for a 2.5 kW unit.
🌿 Noise: as low as 19-20 dB indoors on the quietest setting. About 46 dB at 1 metre from the outdoor unit.
🌿 Planning: most houses do not need planning permission for the outdoor unit, under rules changed on 27 July 2026.
🌿 Not included: hot water. Your immersion or boiler keeps that job.

💶 One Room Costs €2,000-3,500 Fitted, Two Rooms Start at About €4,000

Irish installers in November 2026 price a single wall unit at about €2,000-3,500 fitted. That includes both units, the pipes, the electrics and the labour. A bigger room needs a bigger unit and costs more.

🔹 Indicative Irish prices, November 2026

🌿 One room (bedroom, home office, garden room): €2,000-3,500 (Complete Cooling, Cork).
🌿 One large or open-plan room: €2,500-4,000.
🌿 Two rooms on one outdoor unit: €4,000-6,500. Three or more rooms: from €6,500, priced after a visit.
🌿 High wall units: from €2,120 including VAT and fitting (Teoair). LG Standard Plus from €2,268, LG Artcool Mirror from €2,643, Daikin Emura from €3,295.
🌿 Low wall (floor level) units: from €2,900. Ceiling cassette units from €3,045.
🌿 Yearly service: about €80-150. Cleaning the filters yourself costs nothing.

🔹 Long pipe runs and first-floor outdoor units push the price up

🌿 Cheapest job: indoor unit on an outside wall, outdoor unit at ground level right behind it.
🌿 Dearer jobs: long pipe runs, first-floor or flat-roof outdoor units, and extra electrical work.
🌿 Paperwork: the fitter must hold an EPA F-gas certificate to handle the refrigerant.

🏛️ SEAI Pays Up to €9,500, But Only When It Replaces Your Heating

SEAI's heat pump grant table and its Homeowner Application Guide list air to air at up to €9,500 for houses and apartments alike. Air to water gets up to €14,500 in a house. The grant is for replacing your heating, so one unit added to cool a bedroom will not usually qualify.

🔹 The SEAI rules, as of November 2026

🌿 Age of home: built and occupied before 2021, with an electricity meter number (MPRN).
🌿 Built before 2007: you need a technical assessment of heat loss, unless your BER shows a Heat Loss Indicator of 2.3 or less. SEAI gives €200 towards the assessment.
🌿 Built in 2007 or later: no assessment needed. You sign a self-declaration form.
🌿 Contractor: must be on SEAI's contractor list for heat pumps. You get grant approval first, then the work starts.
🌿 After the work: a new BER by an SEAI-listed assessor, then SEAI pays.
🌿 Cap: the grant can never be more than the cost of the work.
🌿 Boiler scrappage: since 29 September 2026 the heat pump grant includes €2,000 for removing an oil or gas boiler, solid fuel or storage heaters. SEAI does not say how the €2,000 is counted inside the €9,500 air to air figure.

Some sites still quote older figures of €7,500 or €3,500 for air to air. SEAI's own guide says €9,500, so check your grant offer before you sign. Our heat pump guide covers the other grants.

❄️ A 2.5 kW Unit Cools a Room of About 20 m² for 17-22c an Hour

A 2.5 kW split unit suits a room of up to about 20 m², such as a double bedroom or a home office. At full power it draws 485-630 W, which costs 17-22c an hour at 35c/kWh. A hot evening of 4 hours at full power is about 68-88c.
🌿 It also dries the air: a muggy bedroom feels better as well as cooler.
🌿 It keeps working in a heatwave: the Mitsubishi Electric and Fujitsu 2.5 kW models are rated to cool with up to 46°C outside.
🌿 It slows down once the room is cool: inverter units drop to a low, steady power at the set temperature, so real use is often lower.
🌿 Against a portable unit: no hose out the window, and the noisy part sits outside. See our portable air conditioner guide and fan vs air conditioner.

🔥 Heating a Room Costs About 21c an Hour, Against 70c for a 2 kW Heater

The Mitsubishi Electric MSZ-LN25 gives 3.2 kW of heat from 0.6 kW of electricity. At 35c/kWh that is about 21c an hour. A 2 kW plug-in heater costs 70c an hour and gives less heat. Getting 3.2 kW of heat from a plug-in heater would cost €1.12 an hour.
🌿 Over a year: Daikin's 2.5 kW Perfera uses 659 kWh a year for heating and 101 kWh for cooling under the EU test for an average climate. At 35c that is about €231 for heating and €35 for cooling.
🌿 In cold weather: the Mitsubishi Electric and Fujitsu units are rated to heat down to -15°C outside.
🌿 Best use: one room you sit in all day, an extension the radiators never reached, or a home on storage heaters or plug-in heaters. Our electric heater running costs guide has the heater numbers.

🔹 Air to air heat pump running cost calculator

📋 Popular 2.5 kW Models: SEER 7.4-10.5 and SCOP 4.1-5.2

SEER (cooling) and SCOP (heating) show how much heat a unit moves for each unit of electricity over a season. Higher numbers are cheaper to run.
🌿 Mitsubishi Electric MSZ-LN25 (Zen): 2.5 kW cooling, 3.2 kW heating. SEER 10.5, SCOP 5.2. Uses R32 refrigerant.
🌿 Daikin Perfera FTXM25R: 2.5 kW cooling, 2.8 kW heating. SEER 8.65, SCOP 5.1.
🌿 Fujitsu ASYG09KMCF: 2.5 kW cooling, 2.8 kW heating. SEER 7.4, SCOP 4.1.
🌿 Full cooling power: at full cooling the Fujitsu draws 630 W and the Mitsubishi Electric 485 W.

🔇 Indoor Units Run at 19-22 dB on Their Quietest Setting

The Mitsubishi Electric MSZ-LN25 indoor unit runs from 19 dB to 42 dB. The Fujitsu ASYG09KMCF runs from 20 dB to 40 dB cooling and 22 dB to 42 dB heating. Both outdoor units measure 46 dB.
🌿 Bedrooms: use quiet or night mode. Full power is much louder than the lowest setting.
🌿 Neighbours: the planning rules below set a noise limit at the nearest neighbouring home.

🏡 Most Houses Need No Planning Permission for the Outdoor Unit

S.I. No. 342 of 2026, in force from 27 July 2026, lets you fit an air source heat pump on a house without planning permission if it meets five conditions. The old ban on fitting one on or in front of the front wall is gone.
🌿 Size: all heat pumps together must be no bigger than 2.5 m² in area.
🌿 Edges: at least 50 cm from any edge of the wall or roof it is fixed to.
🌿 Road: it must not stick out over a public road.
🌿 Ground: ground level must not change by more than 1 metre.
🌿 Noise: no more than 43 dB(A), or 5 dB(A) above background noise if that is higher, measured from the nearest neighbouring home.
🌿 Apartments and listed buildings: the rule is written for houses. Ask your council planning office first.

🔄 Air to Air Heats Rooms Only; Air to Water Heats Radiators and Hot Water

Air to air only warms or cools the rooms with an indoor unit. Air to water heats radiators, underfloor heating and your taps, and replaces the boiler. It costs more to fit but gets the bigger grant. See our air to water cost guide.
🌿 Air to air suits: apartments, extensions, garden rooms, single rooms used all day, and homes on electric heaters. It also cools.
🌿 Air to air does not suit: a whole house with radiators and a hot water cylinder. Your hot water still needs the immersion or boiler.
🌿 Leaky homes: insulation comes first, whatever heats the room.

⚠️ Common Mistakes to Avoid

🌿 Counting on the grant for one cooling unit: the SEAI grant is for replacing your heating, with heat loss rules and a contractor from SEAI's list.
🌿 Starting work before grant approval: SEAI will not pay for work done before approval.
🌿 Buying too small: an undersized unit runs at full power all the time, never reaches the set temperature and costs more to run.
🌿 Using a fitter without an F-gas certificate: it is a legal requirement for anyone handling the refrigerant.
🌿 Putting the outdoor unit under a neighbour's window: the planning exemption has a noise limit measured at their home.
🌿 Skipping the filters: clogged filters cut airflow and push up running costs.

❓ Frequently Asked Questions

🔹 How much does an air to air heat pump cost in Ireland?

About €2,000-3,500 fitted for one room, €2,500-4,000 for a large room and €4,000-6,500 for two rooms (Irish installer prices, November 2026).

🔹 Is there an SEAI grant for air to air heat pumps?

Yes. SEAI lists up to €9,500 for all home types, as of November 2026. The home must be built and occupied before 2021, the heat pump must replace your heating, and you need approval before work starts.

🔹 Can I buy a split air conditioner and use it for heating?

Yes, if it is a reversible (heat pump) model. The Daikin, Mitsubishi Electric and Fujitsu models on this page all heat and cool, and Teoair says heating and cooling come as standard on its high wall units.

🔹 Do I need planning permission for the outdoor unit?

Not on most houses since 27 July 2026, if it meets the size, position and 43 dB(A) noise conditions in S.I. No. 342 of 2026.

🔹 Will it work in an Irish winter?

Yes. The Mitsubishi Electric and Fujitsu 2.5 kW units are rated to heat down to -15°C outside.

📚 Related Guides

🌿 Heat Pumps
🌿 Air-to-Water Heat Pump Cost
🌿 Heating Oil Prices
🌿 Heating Oil by County
🌿 HVO Fuel
🌿 Boiler Replacement Cost
🌿 Gas Boiler Service
🌿 Storage Heaters
🌿 Underfloor Heating
👉 All guides and calculators

Climate Jargon Buster is an independent resource. Prices, running costs and specifications are indicative and correct as of November 2026. Grant amounts and rules are set by SEAI. Always check current terms at seai.ie before you sign a quote.