@elton, @kenbone has a lot of Samsung ASHP experience and knowledge. Maybe he can cast some light.

Hi, Bit of an update. I bought a decibel meter and monitored the sound for an evening. It was one of the warm days so I put the thermostat to 22 as room was at 20.5 anyway. At 19.40 temp was 20.5, and at 22.17 it had got to 21.6 - external temp was not much less than 20 so that seems a bit lame to me anyway. Samsung 8k is rated at 48db. During that period of 2.5 hours I measured the noise with the meter 1 metre from front and 1 metre from side. Front reading varied from 49 to 56, and side from 46 to 50 ( although I perceive sound from side angle to be worse). It did go down suddenly to 37 dB just before I turned the thermostat down and went to bed. That was noticeably quieter but unfortunately I could still hear it from inside, whining and speeding up and down so i think the heat pump is just in a stupid place. Next morning it did a DHW cycle and measured 49db 1 metre from side and 54 dB at the front. 

I think the majority of the downstairs noise is the pump noise coming in through the window and patio doors (dg and closed). Upstairs I think vibration in the pipes is being amplified as they go through stud in bathroom and carrying. Also think the tank is making a noise during DHW cycle.

Installers have now decided I need to get a gravel tray installed for them to put the unit on (why they didn't say before is a mystery) before they come back and finalise position of pump, go through my queries, and register it with Samsung.

So, any thoughts on those decibel readings? If you move the heat pump away from the house, what are the disadvantages and limits for pipe runs of flow and return?

@lokisam  Hi, Yes.

First thought - sound meter. Did you buy a class 1 or 2 sound meter? I bought a meter (data logger) off ebay for £50 and found it didn't match one on my iphone. I was a bit suspicious and wanted proper recordings so I shelled out £200 on a class 2 one. Env Health use class 1 but I couldn't afford that. Turns out, using my class 2 one, my iphone app "decibel meter" was far more accurate than the £50 ebay one. Its good as it has a data logger so does it over time.

Second thought - known issues with declared noise levels. There is some debate about sound power level measurements and whether they are actually properly represented by manufacturers. See DESNZ report page 13:

So in essence the 63dB(A) sound pressure/SPL figure may be untrue - and under-reported.

I'm not sure if this feeds into the declared sound pressure levels (SWL) or whether SWL is tested independently but, unless you have  reflective surfaces, the heat pump is faulty, the dB(A) meter is inaccurate or the assessors have botched the assessment, the declared SWL should pretty much be reasonably accurate. You probably need to work through the issues above to discount them until you are down to one.

@editor @kenbone 

Thanks, I would be very interested to hear if you have any thoughts on the Gen 6 noise levels and qualities please Ken or whether noise levels & properties are pretty much the same as any eg Vaillant, Veissmann, Mitsubishi?

@lokisam, with the 20C outside air temperature I would think that the ASHP would not be working too hard so it is concerning that your readings are still above the rated figures. My pump is only doing DHW runs at the moment with air temperatures between 17C and 23C and it is certainly a lot quieter than during the colder months.

@elton that's interesting about your iphone app being more accurate than the ebay sound meter. I had discounted using a phone app as a sound meter as I had no way of calibrating it and also I didn't think the microphone would be suitable. I have had poor results trying to record the ASHP noise with a phone so assumed that the microphone might be tuned for a speaking voice and couldn't resolve the full range of frequencies in the noise and the tonality you mentioned previously. Thinking about it now, the problems with recording might have been to do with the recorder app's compression rather than the microphone and I should try again with lossless raw PCM 🤔 

@sjn yes, when they come back I want to check if they have it on weather dependent. I read that decibel apps work well on iPhone because mic is at a set level, but can be variable on android. I put two apps on my android and they gave massively different readings so I bought a cheap meter off amazon, supposedly accurate to +_ 2db.

Thought it might be useful to update on this. I sent a formal email to the installers requesting they level the unit, insulate the pipes through wall, nvestigate the noise and give me some way of accessing the info on the cylinder display that didn't necessitate a treacherous trip to the loft plus a few more. After having the installers back, I was still suffering with the noise, including a new high pitched whine from the tank in the loft and they had told me to get an electrician to move the display panel. I raised a complaint with NICEIC and an inspector visited. His report lists quite a lot of issues which don't meet standards and several things to remedy  (unit not properly level, pipes not sleeved through wall, inadequate pipe insulation outside and in loft, no way for consumer to see energy usage, no safe access platform in loft for maintenance, no mcs cert, no handover pack) and also some more info he needs from them (is internal piping insulated, how is it fixed, how is tank supported, where are room by room calcs). Both the inspector and the installer suggested I contact Samsung / Joule about noise issues but they won't help unless it's an equipment fault. So, I have booked an inspection by a longstanding local installer who I should have used in the first place. They are going to assess noise and efficiency and suggest mitigations. Meanwhile I am waiting for the installers to contact me about the remedial works they need to do. Can't say I want them back, but it's the way mcs works so I will have to. I am keeping my fingers crossed that a solution will be reached eventually. Meanwhile, I'm lighting the wood burner and I guess I'll buy some earplugs for when I really need the whole house to be heated.

@lokisam did you sort out your noise issues?

@editor Hi, Thanks for asking. Short answer is not yet but here's an update.

The niceic inspection didn't cover noise but there were plenty of things identified that weren't according to regs and need sorting or evidencing.

An engineer from another company found that weather compensation/water law hadn't been set, so has set that and also put hot water on timer so not coming on at night. Also said unit might be running a bit noisy so is checking with Samsung how to check it according to their guidelines.

Also thinks that having the main flow and return chased into brickwork / behind a plasterboard stud uninsulated or sealed through brick wall was a bad idea and is carrying in / amplifying noise. So, suggests rerouting insulated pipes up outside wall with trunking. NICEIC also picked up on some of this. Sounds like a good idea but I'm a bit worried about attaching to / through external insulation.

The engineer identified the high pitched noise from cylinder as coming from the wilo circulation pump. It's a Joule preplumbed and so the pump can't be relocated ( according to Joule). The noise varies from mildly oscillating tinnitus to "this vehicle is reversing" in the middle of the night. It seems louder in the bedroom below than in the loft. Some people have said they could live with it, but I can't. The noise is constant when heating running, dhw running and when it's off but circulating water to avoid freezing up. No solution to this yet. I'm hoping it's faulty and can be fixed but if not, I have to find a way to muffle or move it.

Original fitters back next week to address niceic list. Second engineer back after that to check a bit more.

On the plus side, the system has coped with the cold spell, though the pump deicing itself is very noisy and clangy.

I think I'll post the two things above as separate short queries to get more ideas.

@lokisam I am following this with interest as I also have recently had a gen6 8 kw heat pump system installed along with the Joule cylinder and Wilo pumps,I also find the pump to be very noisy indeed , I can hear it in my bedroom as it’s only about 3 meters from the window in fact  sometimes it’s quite audible from the top of my driveway and that’s about 30 meters away the sound is definitely coming from the compressor.

Internally the flow and return pipes run through and up the wall into the roof space ( bungalow) and then back down and into a small lean to conservatory that houses the cylinder.

The other issue on top of the heat source compressor is that internally there is a high pitched noise coming from the pipes that’s there most of the time but this I have reduced somewhat by dropping the Wilo pump speeds to setting no 1  also I have managed to reduce this even more by making sure that there is completely no air in the system but this only seems to last a few days and then it returns just out of the blue so I’ve just about given up on that exercise.

The company that installed the system told me to contact Joule and that is next on my list of things to do in an effort to get to the bottom of this but I have a feeling that it’s going to be a bit of an arduous task.