One more thought though, how far is the unit mounted away from the wall? It looks to be rather closer to the wall than ours and perhaps this is amplifying what is already a noisy mechanism; our Daikin heat pump is 33 cm. from the house wall and as we live in an area with a relatively high ambient noise level (any unwanted sound might be described as ‘noise’!) the fan noise can be heard when within perhaps 0,5 metres or less. I suspect in a quieter environment, this range would be extended to 1-2 metres - but no rattle at all. Regards, Toodles

@toodles I can't hear my pump's fan noise at all - it is absorbed in the compressor noise. In any other pump I've heard doing dhw it's the fan noise you hear and the compressor is hardly audible if at all. With my pump the compressor is all you hear.

I've now had two Daikin technicians in, both concluded my pump is in order which doesn't match anything else I've seen or heard with my own eyes and ears.

The bottom line is, they won't do anything about it. If they are correct and my pump is in order, they are selling a very outstandingly noisy heat pump.

Posted by: @sobo

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@toodles I can't hear my pump's fan noise at all - it is absorbed in the compressor noise. In any other pump I've heard doing dhw it's the fan noise you hear and the compressor is hardly audible if at all. With my pump the compressor is all you hear.

I've now had two Daikin technicians in, both concluded my pump is in order which doesn't match anything else I've seen or heard with my own eyes and ears.

The bottom line is, they won't do anything about it. If they are correct and my pump is in order, they are selling a very outstandingly noisy heat pump.

I would suggest that you raise an official complaint through Daikins complaint service.

Ask Daikin to provide a noise measurement test to prove that your heat pump is no noisier than other ones.

If that does not produce any success then try their higher management. Many companies now have the philosophy of 'fob off the customer until they give up'.

@derek-m the noise is in the area of 56dba so within their advertised range. But after going out there and listening to other pumps I can say with full confidence it's a different noise altogether. Other pumps sound like a fan and it's a noise that blends in the background. My pump sounds like a running motor which is a disturbance.

That's my heat pump, doing a hot water cycle:

Happy to hear whether you find the noise in order or not.

I can't take anything directly with Daikin as my warranty is through the installer - it's just one month old. They had two Daikin technicians over who said everything is in order which I find odd. Would be glad to hear from you guys if that's the noise you are experiencing.

@sobo Our Daikin eminates fan noise as mentioned before but the ‘underlying’ sound of compressoe or whatever is not audible like that at all. I daresay there IS some compressor noise on ours but it must be well below the level of the fan noise; as mentioned, we live in an area with high ambient noise due to motorway link road, 3 arterial roads and aircraft!

Years ago, I learnt of the technique used to create the ‘Wall of Sound’ used by record producers of pop music; the recordings are monitored whilst the various strata of the audible range are tweaked to increase the loudness of the overall sound but without significant change to the peak level (imagine a hilly landscape where the valleys are accentuated to even out the overall level. What I am trying to say is that the compressor noise is adding to the overall noise but not exceeding the level of the usual compressor noise - thus ‘no extra noise’ is percieved by a person who may have a certain bias! Regards, Toodles,

Of course I meant the ‘usual overall noise from the fan’, the compressor being masked by the fan noise normally. I note that our Blomberg condensing tumble dryer’s heat pump compressor makes a similar sound to what I think is the compressor element in your Daikin ASHP - without a huge fan of course!

Sound / noise is such a subjective matter as ‘unwanted or annoying’ sound is ‘noise’ whereas your favourite music playing is ‘sound’ and very different! Regards, Toodles.

@toodles I agree about noise being subjective, but curious to know - the sound in my video linked above, is that what you have with your Daikin?

@sobo As I tried to explain (badly I feel!) I have a different model but still Daikin, what I hear from ours is the fan noise but cannot hear the compressor noise that I hear with yours. Regards, Toodles.

@sobo

In your recording the compressor appears to be running quite fast, which would indicate working harder.

I would suggest that you look within the controller and see if there is a reading of compressor speed, gas pressure and temperature etc.

Then try adjusting the system operation to lower the compressor speed and hence how hard it is working. Varying the LWT setting may create the desired effect.

Is your controller set for weather compensation mode?

Hi again @sobo. That video is informative, the noise is the compressor discharge, the pressures are highest during hot water generation when the unit has maximum LWT. Your model states a Sound Power Level of 62dB(A) in the data sheet but the footnote then states this is Sound Pressure Level. If it is sound power level, then in free field this would equate to 53dB(A) Sound Pressure Level at 1m. With two reflecting planes, ground and wall to rear, the sound pressure level at the front of the unit at 1m could be 5dB(A) higher - i.e.: 58dB(A)

Sound pressure level is not to be confused with sound power level - they are different things. It's not uncommon for manufacturers to mix the values up or get confused when quoting them. My Grant 10kW unit, has 62dB(A) Sound power level & 53dB(A) Sound Pressure Level @1m. Same installation, against a wall on the ground and on rubber crumb feet. It has nothing like the dominant compressor sound you capture in your video for the Altherma when generating hot water.

Rather late I know but, as the colder weather is upon us, I went out this morning and have made a video recording with the ‘noise’ from the Daikin heat pump, there is as I have mentioned before a high level of ambient noise from aircraft and road traffic so I have walked around a little so that you might hear the fan noise relative to that emanating at either side and the back for comparison; I don’t think I can hear any specific compressor noise though. Regards, Toodles.