Acoustic enclosure for heat pumps

[ed1178]

Has anyone got any experience of these? My boss (I work for a property developer) has asked me to look into them for a couple of new builds currently nearing completion. Neighbours have complained about noise from newly installed Mitsubishi ecodan heat pumps. It’s a very quiet, rural location so they can be heard some distance away though they are not any noisier than any others we have installed previously.

a quick online search brought up a couple of companies that make bespoke enclosures, circa £2000 plus. They are very bulky extending 600mm to each side and even further in front. Are there any “off the shelf” solutions that are perhaps less bulky even if slightly less effective? Has anyone installed an acoustic enclosure and if so did it make a noticeable difference?

 

[bernardgreen]

Restricting the noise with sound reducing baffles will almost certainly restrict or compromise the air flow through the evaporator unit. This could affect (reduce) the efficiency of the heat pump system.

It is not impossible that the noise from some domestic heat pump systems could be a considered to be a statutory nuisance.

https://www.gov.uk/guidance/statuto...h-complaints#what-can-be-a-statutory-nuisance
https://www.gov.uk/guidance/noise-nuisances-how-councils-deal-with-complaints

 

[ed1178]

Restricting the noise with sound reducing baffles will almost certainly restrict or compromise the air flow through the evaporator unit. This could affect (reduce) the efficiency of the heat pump system.

It is not impossible that the noise from some domestic heat pump systems could be a considered to be a statutory nuisance.

https://www.gov.uk/guidance/statuto...h-complaints#what-can-be-a-statutory-nuisance
https://www.gov.uk/guidance/noise-nuisances-how-councils-deal-with-complaints

yes, my initial concern was restricting airflow and compromising efficiency. Interestingly the suppliers of the heat tell me the manufacturer has no issue with them and they don’t compromise the warranty though no figures seem to exist for effects on performance. Interestingly I discovered different local authorities have different rules on noise levels and they are “above backgorund” so a heat pump that might be acceptable in town might not be in a quiet village.
This is sure to become a bigger issue in the coming years. Much as I love the technology, I certainly would want my neighbours to install one!

 

[Swwils]

Acoustic measures can be very cheap. Actually knowing where to put them is very hard.

Can you provide a basic layout of the installation and we can give more focused advice.

An ecodan should not be loud at all... It may be misspecified or installed badly.

 

[muggles]

I've got an Ecodan and it's very quiet. It's installed under the window in the hall and I can't hear it at all when stood by the window or from the garden. Putting an enclosure around it will reduce efficiency. They need 300mm behind and to the side, and 2m in front to ensure proper airflow

 

[oldbutnotdead]

Your problem is that the background noise level in the countryside is much lower than in any built-up area, so a device which acoustically goes unnoticed amidst the murmur of distant traffic, factory rumbles etc. stands out like a rock concert in a back garden.
First things to check- is the compressor actually fitted to the house correctly- the few such devices I've been involved with all had some decoupling features (resilient blocks mainly) so mechanical noise wasn't transmitted to the structure.
After that you're almost certainly in the land of big Wendy houses stuffed with rockwool or similar to attenuate the mechanical noise and some sort of labyrinth air path to reduce noise radiation while maintaining air flow. Rather like with thermal insulation, mass trumps most things, an effective compact solution will be pricey and dependent on some quite precise shapes and forms, their performance may degrade sharply with age and accumulation of gunge.