[OpenTRV-interest] First impressions and questions

[Damon Hart-Davis]

> On 25 Jan 2017, at 14:39, Jason Pearce <jason at pearce.org.uk> wrote:
> 
> Hi,
> 
> Received my stats hub and valve earlier this month - thanks.
> 
> It's working :)
> {"@":"F4C780E1ECBF9397","+":6,"tT|C":17,"tS|C":2}
> =F at 20CF;T4 15 W255 0 F255 0 W255 0 F255 0;C5
> =F at 21C0;T4 16 W255 0 F255 0 W255 0 F255 0;C5
> =F at 21C0;T4 17 W255 0 F255 0 W255 0 F255 0;C5
> {"@":"F4C780E1ECBF9397","+":7,"L":24,"vC|%":1358}
> =F at 21C0;T4 18 W255 0 F255 0 W255 0 F255 0;C5
> =F at 21C0;T4 19 W255 0 F255 0 W255 0 F255 0;C5
> {"@":"F4C780E1ECBF9397","+":8,"T|C16":361,"H|%":48,"O":1}
> =F at 20C9;T4 23 W255 0 F255 0 W255 0 F255 0;C5
> {"@":"F4C780E1ECBF9397","+":9,"T|C16":359,"L":24,"v|%":0}
> =F at 20CA;T4 27 W255 0 F255 0 W255 0 F255 0;C5
> {"@":"F4C780E1ECBF9397","+":10,"tT|C":17,"tS|C":2}
> =F at 20CD;T4 31 W255 0 F255 0 W255 0 F255 0;C5
> {"@":"F4C780E1ECBF9397","+":11,"H|%":49,"T|C16":352,"O":1}
> 
> 
> What do the =F lines signify ?

Internal status reports in ‘;’ separated format.

Look at:

enum Serial_LineType_InitChar

in:

https://github.com/opentrv/OTRadioLink/blob/master/content/OTRadioLink/utility/OTV0P2BASE_Serial_IO.h

for the ‘special’ meaning of some lines based on their initial character.

Look at:

serialStatusReport()

in:

https://github.com/opentrv/OpenTRV-Arduino-V0p2/blob/master/Arduino/V0p2_Main/UI_Minimal.cpp

for a description of the status line format.

> 
> 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

We do want to shrink it; there is a lot of scope to do so.

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

We intend to reduce noise levels in a number of ways.

> 
> Thoughts/questions
> - How does occupancy work during the daytime when we have daylight ?

This is most of an issue in the shoulder seasons.

Manual controls will continue to work.

Other sensors can be added.

There is specific support to weakly detect extended periods of artificial lighting, eg TV watching in the evenings.

It would be good to extend such alternatives.

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

Not particularly.

I continue to recommend keeping internal doors shut in general into (a) rooms that you are trying to heat to keep the heat in and draughts out (b) rooms that you rarely use to allow them to become less of a heat sink and to reduce condensation risks in them.

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

The stats hub will become two way.  However, overriding the temperature on the dial in this style of valve may be confusing.

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

Yes, I would like to continue a split-unit design somehow; two users of that style of OpenTRV that I visited today are very happy with it.

> 
> If it passes the wife noise acceptance test, when might more valves become available :) 

Possibly just after you want them, as they emerge from the end of the current main trial for example.  We have not ruled out a special new run of these valves, but don’t hold your breath.

Rgds

Damon