High Pitch Noise Generated by Some Heat Pumps / Mini-Split Ductless Air Conditioners

[K.A.]

Some heat pumps and mini-split (ductless) air conditioners (especially the outdoor and indoor units) generate a relatively high-pitched noise when operating. I suspect it is caused by high-frequency switching circuits in the unit's power supply, as this is a known issue with other electronics like chargers and some electronic inverters that have cheaper components and/or lack glue around some of the components, giving off this noise.

Asking the manufacturers is pointless; they only focus on the noise generated by the fans inside and do not have any measurements of the high-pitched noises. I have emailed many vendors and manufacturers.

Does anyone have any recommendations for units/manufacturers that sell units that do not generate high-frequency noise?

 

[Sadnoise]

Perhaps the indoor unit can be tested. I assume you are talking about air-to-air, not air-to-water. In the latter case, I would focus on isolating rather than preventing it.

It's more difficult with air-to-air. Perhaps it can be tested in a shop. But for the outdoor unit, there are casings available that seem to do a good job, especially with the high-pitched sounds.

 

[2noist]

Does anyone have any recommendations for units/manufacturers that sell units that do not generate high-frequency noise?

Did you ever find a good unit?