TRV (thermostatic radiator valves) help wanted: when noise is the most important!

Hi community,
with the increasing gas prices in Europe I am looking at creating a more efficient home. I’ve decided to invest in some TRVs. The basic requirement is for them to be Zigbee devices that I can control via my sonoff dongle plus coordinator and zigbee2mqtt and … to be quiet when operating!. And of course, the batteries should not run out insanely fast…

Most topics here and even reviews found on google rarely consider how important the sound of these actuators is, but for the best seamless experience (and wife approval which is a very light sleeper) they need to be quiet in operation.

So please, share your experiences - what TRVs do you have, how quiet are they, are there any videos that show them in operation and which ones would you recommend?

TRV devices are sitting idle most of the time as they have just a physical spring inside them. When they need to move the spring, the motor inside smart TRV would make noise. Also, in regular cadence, they will do full motion but rest of the time they will be silent.

Are you worried about motor sound? Or you are worried that they will make sound when sitting idle

I have four Saswell Wifi Smart TRVs and they’ve been installed for two years.

They are: Reliable, accurate. No failures. They can be overridden locally, or child-locked.

They were easy to install using a decent Zigbee stick and Z2mqtt. They show up with temp actual, target, Mode (Heat/Auto/Off). Reception is good - they work across my house including through four concrete block walls. for one of them.

They use AAA batteries (3x or 4x, I forget which) which last well. All year for me, but obviously depend on how often you change them.

Setting automations in HA is straightforward.

Noise: The have an electric motor and a reduction gearbox. They make a noise. I suspect all of them will make a similar noise. I don’t consider it intrusive and, like all house noises, you don’t notice them at all after a short period.

The only negative I have about these ones is the local temperature buttons are back to front. Left button is +, right button is -, with an lcd in the middle to show target and actual.
With two of us working from home, they do allow us to automatically control which rooms get warm and which don’t. I have automations to set temps for Weekday-Daytime and Weekend-Daytime, and also for Evenings and one for Overnight.