A modern air source heat pump emits 50–65 dB(A) sound power, heard as roughly 35–48 dB(A) at 3 metres — between a quiet library and light rainfall. EU Ecodesign Regulation 813/2013 caps outdoor sound power at 65 dB(A) for units up to 6 kW and 70 dB(A) for 6–12 kW units; premium units run 10 dB below those limits, and night modes cut output further.
How many decibels is a typical heat pump?
Two different numbers appear on datasheets, and confusing them causes most noise disputes. Sound power (LWA) is the total acoustic energy the unit emits — the value EU law regulates and the energy label prints. Sound pressure is what an ear measures at a distance, always much lower: in free field, roughly 17–20 dB below sound power at 3 metres. A unit rated 60 dB(A) sound power is therefore heard at about 40–43 dB(A) from 3 metres — comparable to a quiet office. Modern inverter-compressor units spend most of the year modulated well below full speed, quieter still; brief louder phases occur at full load and during the defrost cycle.
What are the EU Ecodesign noise limits?
Commission Regulation (EU) No 813/2013 sets binding maximum sound power levels for heat pump space and combination heaters, applicable since 26 September 2015:
| Rated heat output | Outdoor limit (LWA) | Indoor limit (LWA) |
|---|---|---|
| ≤ 6 kW | 65 dB | 60 dB |
| > 6–12 kW | 70 dB | 65 dB |
| > 12–30 kW | 78 dB | 70 dB |
| > 30–70 kW | 88 dB | 80 dB |
These are manufacturer compliance ceilings, not neighbourhood targets — good residential units undercut them by 5–15 dB. The declared sound power also appears on the EU energy label, so models can be compared before purchase. The Ecodesign revision consulted on through January 2026 foresees a rescaled A–G label with a dedicated noise pictogram and tighter acoustic requirements; check the current adoption status before relying on the new values.
What noise rules apply at the property boundary?
National and local rules govern what neighbours may actually receive, and they bind the installation, not just the product. Germany's TA Lärm allows 35 dB(A) at night outside bedroom windows in purely residential areas; the UK's MCS planning standard works to 42 dB(A) at the nearest neighbour's window for permitted development. Subsidy schemes add pressure from the market side — Germany's BEG programme funds only air source units that undercut the Ecodesign sound power limits by at least 5 dB (verify the current technical annex, as the required margin has been under revision). Siting maths is simple and unforgiving: every doubling of distance cuts sound pressure by 6 dB, while each large reflecting surface near the unit — a wall or a corner — adds roughly 3 dB.
How can you make a heat pump quieter?
Six measures cover almost every case: choose a unit with low declared sound power (50–55 dB(A) class); site it away from bedroom windows — yours and the neighbour's — avoiding corners and echo-prone passages; mount it on anti-vibration feet, never rigidly bolted to a bedroom wall; keep airflow paths free so fans never work against obstructions; activate night mode, which caps fan and compressor speed during set hours at a small capacity cost; and size correctly, because an oversized unit cycling at full power is louder than a right-sized one modulating gently — one more argument covered in what size heat pump do I need. A monoblock puts all noise outdoors, while a split adds a quiet indoor module; the outdoor comparison is otherwise similar.
Are heat pumps getting quieter?
Markedly. Larger slow-spinning fans, asymmetric blade profiles, compressor encapsulation and smarter defrost logic have brought premium residential units from the regulatory 65 dB ceiling down to 50–55 dB(A) sound power over a decade — a reduction of more than half in perceived loudness. With 2.88 million units sold in Europe in 2025 (EHPA, +13%), acoustic refinement has become a core competitive metric, and manufacturers such as Solimpeks publish the declared noise level of every heat pump model in their technical data.
Frequently asked questions
Is a heat pump louder than a gas boiler?
Indoors, no — the heat pump's noise source stands outside, while a boiler burns and vents inside the house. At the outdoor unit a heat pump is comparable to an air-conditioning condenser; at 3 metres a good unit is quieter than normal conversation.
Will my heat pump disturb the neighbours at night?
Not if sited to the national limit — typically 35–42 dB(A) at the neighbour's window, which a 55 dB(A) sound power unit meets at a few metres' distance. Night mode and avoiding reflective corners provide extra margin.
What is the difference between sound power and sound pressure?
Sound power is the total noise the machine emits and is what EU regulations limit; sound pressure is the level at a listener's position and falls about 6 dB per doubling of distance. Always compare units by sound power and assess neighbours by sound pressure.
Why is my heat pump louder in freezing weather?
Full compressor speed and defrost cycles raise noise for short periods in deep cold. This is normal; if it persists, check for ice build-up, fan obstruction or vibration transmission through the mounting.