When most Irish homeowners talk about installing a heat pump, they mean an air-to-water system. But air-to-air heat pumps are also grant-supported by SEAI and suit some home situations better.
How each system works
Air-to-water heat pump:
- Extracts heat from outdoor air
- Transfers it to water in a closed circuit
- Heats your radiators and/or underfloor heating
- Heats your domestic hot water cylinder
- Replaces your oil or gas boiler completely
Air-to-air heat pump:
- Extracts heat from outdoor air
- Delivers warm air directly via indoor units (like a reverse air conditioner)
- Can also cool in summer
- Does not heat domestic hot water. You still need a separate hot water solution.
- Common in new apartments and commercial settings
SEAI grants comparison
| Air-to-water | Air-to-air | |
|---|---|---|
| Unit grant | €6,500 | €7,500 |
| Central heating upgrade | €2,000 | ✗ Not available |
| Renewable heating bonus | €4,000 | ✗ Not available |
| Maximum total | €12,500 | €7,500 |
The individual scheme gives air-to-air a higher unit grant (€7,500 vs €6,500), but air-to-air can’t access the central heating or renewable bonus grants.
Which is right for your home?
Choose air-to-water if:
- You currently have oil or gas central heating and want to replace it completely
- You have or want radiators / underfloor heating
- You want a single system for both space heating and hot water
- Maximum SEAI grants are important to you (up to €12,500 total)
Consider air-to-air if:
- You’re in a new-build apartment with no central heating
- You want summer cooling as well as heating
- Your home is very well insulated and you have a separate hot water solution
- You’re adding supplemental heat to a property with electric storage heaters
Installation comparison
| Air-to-water | Air-to-air | |
|---|---|---|
| Replaces boiler | ✓ Yes | ✗ No |
| Heats hot water | ✓ Yes | ✗ No |
| Summer cooling | Some models | ✓ Yes |
| Typical install time | 2–4 days | 1–2 days |
| Installation complexity | Higher (pipework) | Lower (ductless) |
For most Irish homeowners switching from oil or gas, air-to-water is the right choice. See our full heat pump cost guide for installed price ranges.