[OpenTRV-interest] First impressions and questions

[Simon Hobson]

Jason Pearce <jason at pearce.org.uk> wrote:

> First Impressions
> - It's big !! - for some reason, my impression from looking at the opentrv/earth websites was that this would be smaller than it is

I'd been wondering about that, hard to tell from a picture, but just scaling from the mounting screw ring indicates that it's not small ! Looks something like 50% wider and 150% taller than my existing heads.

I guess that's one of the compromises from being a small manufacturer. If designing from the outset to make millions of them, then more custom parts becomes more practical, and sizes can be got down.

> - It sounds a little noisey - I've just installed it in the bedroom to see if it passes the test with my wife :)

I suspect some noise damping on the motor/inside teh case might help with that, at least from the photos I've seen online.

> - If opentrv turns off one room because it isn't occupied, do we risk draughts if one room becomes colder than another ?

That's always a risk if rooms are at different temperatures. Cold air will spill along the floor to the warmer room, while warm air will flow across the ceiling in the other direction. On the other hand, with our house I don't think we'd be able to differentiate between that and the regular draughts we have !

> Future - will the following be possible
> - remote control of target temperature per TRV (will the stats hub become two way) ?

It's been indicated that such things (specifically 2-way comms) is likely to come in the future - when they've worked out how to do it securely AND without killing battery life. Power considerations are different between "wake up radio, send burst of data, turn off radio" and "be ready to receive information IF it's sent".

> - remote temperature/occupancy detector - some of my radiators are behind furniture - not ideal, but affects the detection of the room temperature

That's already possible if you get the soldering iron out ;-)