Recommendations
A heat pump can be noisy. It is therefore advisable to install it away from your living areas and those of your neighbours! If you can still hear your heat pump and it is disturbing you, there are solutions to reduce the noise: soundproofing screens and other anti-vibration blocks to separate the appliance from the building and limit the propagation of vibrations. Also remember to orientate the module correctly and not to place it in a corner or too close to a wall: this would create a resonance chamber and amplify the noise of the device.
You should know that there is no specific obligation of means for the installer. On the other hand, it is the ambient noise that is regulated. The installer’s responsibility could therefore be called into question if the installation does not comply with the noise nuisance criteria: a complaint from the neighbourhood may indeed lead to a noise level verification procedure, which in turn may lead to the obligation to dismantle in the event of non-compliance.
To give you a little more assurance and clarify responsibilities, you can ask the installer to undertake to ensure that the installation complies with the maximum noise level, and for this to be mentioned in writing in the commitment documents. It is then up to the installer, as a professional, to implement the necessary measures to ensure that your installation does not cause noise pollution.
The regulations set precise limits to the noise that is permissible in the residential sector. The unit of measurement for noise volume is the decibel or dB(A). However, this figure obviously depends on the distance from the measuring point to the transmitter. The sound level of a heat pump usually varies from 45 to 65 dB(A) depending on the model, with possible peaks in defrost mode. To give some references, the noise level of a flat with an open window overlooking an active street is 50 dB(A), a hoover 65 to 75 dB(A)
Since 2006, the threshold limit at which an infringement can be established has been lowered to 25 dB(A) when the ambient noise is measured inside the main rooms of a dwelling, with windows open or closed.
Can I install my outdoor unit in an isolated room in the house?
Even if the idea is good in principle, since you could benefit from the preheating of the air by the veranda, which would act as a greenhouse in winter, the air flows required for an air-source heat pump are generally far greater than the production capacity of the buffer space.
On the other hand, there is a risk of transmitting a high level of noise to the house. Therefore, we do not recommend this type of installation. Instead, try to install the outdoor unit on the warmer side of the house, taking care to limit noise pollution to the house as well as the neighbourhood.