I like my nest, it’s definitely kept the house warmer in the winter this year, it’s probably used a similar amount to regular heating when it’s on as it seems to be on more often but keeps a better temp over the whole day than just freezing or baking like regular timed thermostats. Then when I’m away it knows and turns it off.
Been bugging me for about a week though since turning the hot water down to an hour in the morning and an hour at night it seems to be randomly firing and I couldn’t work out why. Eventually Google fu shows it’s anti legionnaires mode… if you don’t heat the water for 2 hours consecutively in 48 hours it does it for you. Clever stuff.. it’s now turned off!
Integrates well with other automation, Alexa seems to better with hive though, but I don’t have an Alexa.
Edit: woody when it fires randomly check the screen, I was getting annoyed with it but if it has a little yellow drop it’s as above, anti legionnaires mode.