Air-water heat pump very loud

Hello,

behind our two-family house is the air-to-water heat pump. Our new neighbors (3FH) are very nice. The neighbors on the ground floor are experiencing their first winter in the new building and hear the air-to-water heat pump operating at full capacity.

They find it very loud when it runs, for example, in the evening at below zero degrees (understandable since the house is being heated).

The heating engineer says yes, you can "throttle" the air-to-water heat pump in the evening/night hours so that it doesn’t run as strongly and isn’t as loud, but he would advise against it because

1 - the house cools down
2 - the air-to-water heat pump risks freezing since the heating rods are also throttled

What do you say about this? Are there permissible decibel levels?

1 meter in front of your neighbor's window, it may be 35 dB(A) (nighttime). That is not much..

Which model do you have?

Hi,
unfortunately, this is a fundamental problem with the systems. At night in winter, these things make a hell of a racket.
Although the noise is unnecessary, below -5°C they will run anyway as pure electric heating. The fan noise is then just a bit of a show for your conscience.
But honestly, I don’t really understand why you run them at night. (Even if almost everyone does). The efficiency of these heaters depends directly on the outside temperature. The higher, the better. So especially in winter, you should rather heat during the day. At night, they should actually be able to stay off if your house is properly insulated.
I know, hardly anyone does it that way... but at least that was the intended purpose of these things....

Best regards,

Andreas

The paramedic told me that at below zero degrees it has to stay on at night so it doesn't freeze... hmm no idea

what is supposed to freeze there???? The refrigerant???;) By running it, the outdoor unit gets colder, as heat is supposed to be extracted from the surroundings there. Sure, in freezing rain a stationary fan could get stuck, but that is rather the exceptional case, right?