Is the air-water heat pump too loud?

Hello everyone,

we have an air-to-water heat pump. It is located about 5-6 m from our bedroom window. At night, we wake up due to the noise of the unit, especially during the defrost mode it is really clearly audible. The manufacturer no longer does anything and says that this has to be clarified through an expert report.

I have now taken the trouble to borrow a semi-professional measuring device, PCE Instruments PCE-322A class II sound level meter.

At 11 p.m., at a distance of 6 m, I measured a background noise of 37 dB with it. When the unit is on, I measure 45.5 dB to 46 dB. And this is not even in defrost mode.

From my understanding, this is way too loud, but I am not a technician.

Could someone help me and assess the values?

Maybe I can get the manufacturer to engage more.

Best regards and many thanks!
Stefan

Two questions regarding this: first, which air-to-water heat pump is it? And second, why does the system go into defrost mode at the current temperatures?!?

Regarding your measured 46dB... it first depends on how the 46dB were weighted, but basically 46dB is anything but loud. For comparison, a refrigerator is between 40 and 50dB. However, one must not overlook what type of noise emission it is. 50dB white noise is more pleasant than 50dB sinus tone.

Nevertheless, I am surprised, 46dB should not be audible with the window closed.

greetz

Hello and thank you very much for the response.

The unit is located about 50 cm right in front of a house wall. It currently does not go into defrost mode, but at some point it will again, and I want to clarify the issue. Even in normal mode, the unit is clearly audible.

We usually sleep with the window open.

What interests me: Using a sound calculator on the internet, I come to a dB value of 45 dB for the unit based on the measured values. Is this correct?

And I find 45 dB quite loud at night when it is directly in front of the window. It is also not a pleasant wind noise; the unit sounds like an old refrigerator, and when it goes into defrost mode, I have a clearly audible whistling tone in the bedroom.

We are located in a purely residential area, and according to the law only 35 dB may be measured at night. 45 dB would then be considerably louder, that is, 45 dB is perceived as twice as loud as 35 dB.

As I said, I am not familiar with this, and therefore my questions.

Regards and thanks!
Stefan

Even if the device is only 35db loud (afaik measured at a distance of 10m), it won't help you if the unit is positioned under the open bedroom window. That is simply a planning error and hardly the fault of the device imho

Hmm, yes, I think so too, but the train has now left the station. I originally wanted to have the system in the garage, everything was planned accordingly, but the installer convinced me with the statement that I wouldn't hear the system in the bedroom. Unfortunately, we are far from that.

Very annoying.

Thanks anyway for the answers.

In the garage is probably not possible because the device needs airflow. Additionally, a garage might act like a resonator. You can certainly have the device operated by coin insertion.