Actual Noise Levels
The Vaillant aroTHERM Plus produces 48 dB(A) at 3 metres at full load. For context:
- A whisper: 30 dB(A)
- A refrigerator humming: 40 dB(A)
- Vaillant aroTHERM Plus: 48 dB(A) at 3m
- Normal conversation: 60 dB(A)
- A washing machine: 70 dB(A)
At the nearest neighbour’s window (typically 5–10 metres away), the sound level drops further to around 35–42 dB(A) — quieter than a fridge.
Most of the time, your heat pump will not be running at full load. At partial load, noise levels drop significantly — often below 40 dB(A) at 3 metres.
MCS Noise Assessment
As MCS-certified installers, we carry out a formal noise assessment for every installation (using the MCS 020 planning standard). This calculates the sound level at the nearest noise-sensitive point (typically a neighbour’s window or bedroom).
The permitted development limit requires the noise level not to exceed 42 dB(A) at 1 metre from a neighbour’s habitable room. We model this during the design phase and position the unit accordingly. If a particular location does not meet the noise criteria, we find an alternative position before any work begins.
Placement Tips
Good placement makes a big difference:
- Distance from boundaries — Every doubling of distance reduces noise by about 6 dB(A).
- Avoid reflective surfaces — Placing a unit between two walls can amplify noise. Open positions are quieter.
- Soft ground — A unit on grass or gravel is quieter than one on concrete, which can reflect sound.
- Anti-vibration mounts — We always install rubber anti-vibration feet to prevent structure-borne noise.
- Acoustic barriers — In tight spaces, a simple fence or planted hedge can reduce perceived noise significantly.
Frequently asked questions
The Vaillant aroTHERM Plus produces about 48 dB(A) at 3 metres at full load — quieter than normal conversation (60 dB) and similar to a fridge. At a neighbour's window it typically drops to 35–42 dB(A).
Very unlikely. We carry out a formal MCS 020 noise assessment for every installation to ensure the level at the nearest neighbour's window stays within permitted limits, and position the unit accordingly before any work begins.
Under permitted development the calculated sound level must not exceed 42 dB(A) at 1 metre from a neighbour's habitable-room window. We model this at the design stage using the MCS planning standard.
Good placement is key: distance from boundaries, avoiding enclosed reflective corners, anti-vibration mounts and, where needed, an acoustic barrier or hedge. We build all of this into the design.
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