[OpenTRV-dev] UI simplification

[Damon Hart-Davis]

Hi,

Our all-in-one valve being production-engineered right now looks very like a normal mechanical TRV.

I was just having another think about how people use and abuse existing TRVs, and I think that I may have found a useful simplification of the UI, but I’d like some opinions.

1) If one of the new OpenTRV units was installed without any instruction manuals I think most users would expect that if they turn it right down it will be off or providing frost protection.

As things stand it will be at a base temperature of ~16C and could still be in ‘WARM’ mode all the time for example.

So the first thought is that if the pot is turned right down (say) into the bottom 10% of the range it should force FROST protection mode (rather than completely ‘off’).  No other clicking of buttons necessary.

So that makes it intuitive for people to turn the thing off.

2) The way that people tend to abuse TRVs when the room is too warm is to turn them right up to max and then forget about them, thus causing overheating (and often a bout of wasteful window opening).

Supposing instead that turning the dial right up (into the top 10% of the scale for example) engages ‘BAKE’ for the normal 30 minutes and then reverts to a decent, safe, reasonably efficient 18C or so, ie in ‘WARM’ mode.  That should kill the overheating problem.  It also means they have a known simple way to force the radiator on, even if not the most subtle.

If someone is more thoughtful in their operation and adjusts to near the top of the range but out of that top part then they can select a steady target temperature of up to ~23C, and using the button action they can switch the stuff between FROST, WARM and BAKE modes at will at any temperature in the range ~16C to ~23C.

The key point here is just using the temperature dial will often be enough and will generally avoid overheating.

The aim is for no one to ever have to refer to an instruction manual to get basic functionality (though it may make our printed legend for the dial a bit more complex!).

Does that sound like a good idea?

Rgds

Damon