I’m not an expert regarding noisy installations but I installed my own 5kW Samsung and we don’t hear a peep from it. 

A couple of things come to mind. Pumps do vary as to how noisy they are. Good quality ones should be very quiet. 

Whooshing noise sounds like there may be air in the system that will need to be bled out. 

Do you think the noise from the heat pump might be vibration. If so it should be decoupled from the pipe work as it may be pipes banging on surfaces causing it. The fact that your neighbours don’t think it’s noisy supports this. 

I think there is a quiet mode on the Samsung but I doubt that will help much if it’s vibration causing the problem. 

Perhaps some installers on here can give you more experienced advice. 

Posted by: @lokisam

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1. The pump is louder in general than I expected - often louder than a fridge, and louder than some I have seen at other houses (some very quiet). It also surges / revs up.

2. I can hear it all the time in the living room - sometimes quieter, sometimes louder, and I know it's going to drive me nuts over winter.

3. I can hear start up noise and water tank noise (whooshing) in the bedroom which has woken me up on occasion. 

ASHP noise from the outdoor unit should not transmit through solid walls and DG windows to inside. You would hear it through open windows however. If it's clearly audible, are there reflective surfaces bouncing the noise from the ASHP back to the house and your living room? These can amplify the noise from an ASHP, which is quoted by the manufacturer in free field 'open space' conditions. In practice, most ASHPs are adjacent to at least one or two reflective planes. Noise inside does as @bontwoody suggests suggest noise transmission through pipework. Pipe connections on the AHSP should be flexible pipes and the ASHP should be on rubber crumb anti-vibration feet. That reduces noise and vibration transmission, but doesn't eliminate it. Pipes through the house solid wall should have an insulation sleeve, not bare copper against brick/blockwork. Pipe clips on pipes should be insulated cushion type, not solid metal. It's often the case that poor installation can allow noise transmission paths along the pipework and into the house.

Whooshing is as @bontwoody says, air and/or low pressure in the system. On newer installs air is released from the water used to fill the circuit, and this has to be periodically vented from automatic or manual vent valves. The system pressure may need topping up when releasing air. Eventually the circulating water will be de-aerated and, with adequate pressure and no leaks, the circulation should be quiet. A small amount of system white noise through piping and radiators may be expected when the ASHP is running, as ASHPs have higher flow rates than fired boilers. It should not be intrusive however. TRVs can generate noise on radiator inlets, and that's another reason why they are best avoided, using weather compensation control instead.

@lokisam, I also have what feels like a very noisy 8kW Samsung ASHP. The noise gets all through the house (new build, single story, 2 bedroom, underfloor heating and hot water) and is also very noticeable outside - luckily we don't have any near neighbours as I can sometimes hear the pump quite a way from the house.

The noise from the pump appears to be from the compressor, rather than the fan. About half the time the pump will putter away and it's just a background noise in the house (very similar to the oil boiler in our old hose) but the remainder of the time it is very much louder to the point that it will wake us up during the night. The level of noise does vary with the amount of work the pump is doing, so much noisier during colder spells.

I have read that an ASHP should sound a bit like a fan and a microwave. When my pump is running quietly this is a good approximation but at other times it can sound more like someone using an electric pressure washer or an impact driver.

Like you, there is a period of startup noise. This can be loud and very obtrusive even in milder weather when the pump will settle to running quietly after 30 minutes or so.

The compressor also sounds like it is revving up and down a lot all the time, leading to a continual change of noise frequency which is probably more annoying than a constant noise would be. It is almost like it is struggling to find the correct speed - it reminds me of badly tuned PID controllers from a previous life. This variation is not related to cycling (which does happen when it is very mild) but occurs when the pump is trying to achieve the target water temperature (LWT) for the water law settings and the measured LWT fluctuates all the time. The compressor noise doesn't vary like this when it's on a DHW cycle.

There was a lot of circulation noise at first but the plumber who installed the system did some adjustments of the circulation pumps and this reduced it a lot. It's a standard Joule pre-plumbed install with a primary circulation pump between the ASHP and the buffer in the Joule tank and two circulation pumps on the UFH circuit.

I raised the noise issues with the Joule appointed commissioning engineer during the first annual service but he said it was no worse than the 16kW Samsung system at his own house. He did move some insulation inside the pump to stop a pipe vibrating which did modify the noise a bit.

@allyfish, thanks for the comments on noise transmission into the house. I have checked that the flexible pipes, anti-vibration feet, and insulation sleeves on the pipes passing through the outside wall are all fitted but inside it looks like the pipe clips on the primary and heating circuits might just be solid plastic clips. As these are clipping the pipe to the timber frame of the house, the vibration might be turning the house into it into a sound box.

I am now waiting for a visit from another company of ASHP engineers to get a second opinion on the installation and the noise issues. My biggest problem is getting someone to visit as we are a good two hour drive North West of Inverness and everyone is really busy with new installations nearer to home.

I will let you know if the new engineers come up with any suggestions.

Posted by: @sjn

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As these are clipping the pipe to the timber frame of the house, the vibration might be turning the house into it into a sound box

Timber framing that is dry lined can be a very effective noise amplifier to anything fixed to it. A good analogy is a carelessly mounted bathroom extractor fan screwed direct to timber ceiling truss frames and the very intrusive noise it can produce.

Thanks @allyfish - yes dry lining on a timber frame.

I'll get the clips changed to insulated/cushioned ones to see if that reduces some of the noise transmission in the house. Access might be a challenge as I doubt the existing clips were fitted with replacement in mind 🙄 

It sounds to me like there is both vibration and fan/compressor noise.

Is the unit on a bracket or on the floor? 

I spoke to a reputable installer a few weeks back who says Samsung Gen 6's can be noisy & can have coarse tonality compared with other models although quite a few folk say theirs are quiet (and the latest, priciest models are probably quieter). Both Persephone and I have issues with noise from Samsungs.

1/6 UK owners are unhappy with noise from their unit (Nesta's large scale survey 2023). Noise issues are often palmed off as simply bad installation which allows the damaging & false claim that noise issues are simply a "myth". Clearly isn't for you or Sjn and many many others (the 1 in 6).

Fingers crossed it will be a simple fix. Implications for health and wellbeing, the value of a home, neighbours etc etc - noise issues need to be squeezed out both by manufacturers (who should be forced by tighter noise regs to make quieter units) and installers (who should always pay careful attention to noise/vibration rather than seeing noise regs as the nuisance).

See MIS3005-I 6.33, 6.34, 6.35 and Building Regs Part L 6.40 onwards which almost directly copy it and hold the installers to account on that. MIS3005 is mandatory - its required under planning. Building regs are of course mandatory too.

@bontwoody Thanks for responding. What do you mean by decoupling the pipes?

@allyfish Thanks for responding. Although I think the unit is excessively noisy, what you say about vibration makes sense. I've just checked and the lagged flexible pipes are directly connected to solid copper pipes which pass through the solid wall with no lagging or wrapping at all. These pipes then travel up the inside of the living room wall (chased in and fixed with plastic clips with plasterboard over). They then travel up the bathroom wall (solid external wall with stud wall over to accommodate pipework). However, I have stood with my ear to the wall where the pipes are and I can't hear or feel any vibration. Would you expect to, or does it not work like that? 

The unit is sat on rubber anti - vibration feet. It is on patio slabs (concrete) rather than a gravel tray, although I am planning to change that as the patio slabs are not level and therefore the unit is slightly un-level. What you say about reflective surfaces makes sense but I'm not sure what the remedy is. The unit is on the back wall of the living room, near the corner with the detached side of the house along which runs a narrow fenced path. There is an old brick coal shed next to the path about a metre from the heat pump. The noise seems to get sent down the pathway, and sometimes I can hear it on the driveway. The detached neighbours say they haven't noticed it which surprised me. Not sure what can be done about this except maybe a gate to stop the sound travelling (which may make it noisier by the living room).

@sjn Thanks for responding. Pretty much everything you described about the noise is exactly how mine is. I've been to visit 5 other heat pumps in the last two to three weeks. A couple of them, Mitsubishi Ecodan 8.5 and Vaillant 5kw, were virtually silent - just like a fan in a box - (although I suspect the Ecodan might have had the heat exchanger inside as the pipes looked different). The Panasonic 7.5 and Grant (same size as samsung) were about the same as mine on tickover but their owners did not report them surging - or if they did, they didn't notice because they couldn't hear them inside! Then I visited a colleague's Samsung 8k and when it started up, it did the surging noise. I was a bit disappointed because now I think it's just samsungs that are noisy! Regarding the vibration theory. Her main pipes were lagged and ran externally up the wall and into the loft. You could still hear the heat pump in the kitchen behind where the unit stands. 

I've got the installers coming next week to look at it again and then they will register with Samsung. Once that is done, I will approach Samsung for recommendations of people to give second opinions if I'm still having problems. When I was viewing houses to buy, I rejected tons because of traffic noise and now I've found a nice quiet house, I've parked a noisy heat pump outside of it. It's very frustrating. Good luck with getting yours sorted, and if you do get any insights from an engineer's visit, do let me know.

@elton Thanks for your reply. It's on the patio (concrete slabs) on anti-vibration feet but it's not 100% level because the patio isn't. Just spoken to the installer who recommends I get it levelled on a gravel tray before contacting Samsung. Would have been really useful if they'd said that at the start - much easier to remove slabs if there's not a big heavy box in the way!

I think it's compressor noise as well - I am wondering if it is working harder than it needs to for some reason.

Thanks for all the responses. The general consensus seems to be that vibration through pipes, compressor noise, noise bouncing off hard surfaces could all play a part, plus air in the DHW causing whooshing.

Would anyone feel able to comment on whether big rads (tripples) not being hot all the way down after an hour is normal? Smaller rads are fully warm by this point.

Any thoughts on pros and cons of moving the unit to the far side of the patio (2-3 metres from the house) - would be sat at a slightly lower level and I could put a fence behind it - would move it away from hard surfaces it is currently bouncing off?