You should not hear a buzzing noise.
It's meant to be installed inside some kind of enclosure but it will work, just make sure you connect a ground wire to it.
Without knowing the amperage draw of the UV lights I can't say. As long as you don't exceed 40 VA the transformer should be fine for 24/7 usage.
I am doubtful on a 24v one for I needed a 16v transformer that I bought here on Home Depot.com for my Video doorbell Pro. So I would check on the voltage requirements on your model
This is a 40 VA transformer and can handle multiple thermostats. It should be able to handle a thermostat and door bell as long as the door bell is rated at 24 volts.
The wiring is not aluminum and copper is always the best choice.
Hi Hugh, thanks for your question. The Honeywell Home 24-Volt Transformer can be used to supply 24 VAC to low voltage thermostats when needed. If you have additional concerns, we would recommend checking with Nest as they will know more about their thermostat requirements. Hope this helps!
It has more power than you need but will work fine in your application.
The recommend install for this transformer can be found in the manual. If you need additional assistance, please reach out to our support at 1-800-468-1502.