Posted: 2022-11-29 10:00 AM . Last Modified: 2022-11-29 10:01 AM
I am using the Drayton Wiser system in the UK, and generally very happy with it. Last night it was pretty cold, and I noticed that the Wiser App was showing my local temperature as 7 degrees Celsius. It felt colder than that and I noticed that different forecast apps showed a lower temperature at the same time.
Where is Wiser getting its temperature data from for my location?
Posted: 2022-12-15 04:11 PM
I'm in the UK too and my Wiser app (6.1.5) has been showing 2 to 3 degrees all week although all my other apps have been consistently showing minus temperatures, as has the local weather forecast on TV.
My system is connected via opentherm and I thought it had some kind of weather compensation going on, if it has it's not getting the right information.
Posted: 2022-12-15 05:17 PM
The Weather Panel in my app. is currently showing 0°C, but my own DS18B20 based sensor in the shed reckons it's -5.3°C. But there again, living half-an-hour from anywhere, I don't know where it could get a decent reading from.
I can't spot any 'weather-related' information in the data that the API returns (whereas longitude/latitude & sunrise/sunset times are there).
Maybe it's just used by the 'Insights' stuff?
Posted: 2022-12-18 06:11 PM
I live out in the boonies a bit myself but still find the Wiser weather panel is very poor when compared to the other weather apps out there. I too have a sensor on a pole above my garage and that and all the other apps are within a degree of each other, unlike the Wiser weather panel.
I don't think the opentherm connection can be using any sort of weather compensation as it's commanding a high flow temperature (80C) for an outside temperature that it thinks is 4C.
I think you must be right and it's only using the temperature for the insights graph.
Still very poor though, doesn't make the graph very meaningful when looking at how the weather affects the heating.
Posted: 2022-12-19 01:00 AM
I wouldn't dis the app too much. There are numerous things that need sorted but the Insights bit does OK IMO (More culpable is the energy supply companies whose smart meters don't work and never did - but that's another rant for elsewhere).
I enclose a screen shot of the supplied "Wiser" outside air temperature (OAT) and the temperature trace of OAT recorded by a Wiser display/room thermostat that I put in a zip bag and placed in a shaded spot under the picnic table and 60cm above the ground. The traces are markedly different. If explained by systematic error alone, I would expect a trace consistently above or below the supplied one.
I believe the supplied temperature comes from Leuchars air base, some 10 miles away and despite being close has a slightly different weather microsystem than our garden. Maybe no surprise at all.
BTW most airfields in the UK record temperature, humidity on a minutely or hourly basis and the internet weather sites simply lift this data https://www.degreedays.net/ is an interesting site.
Regarding the high boiler flow temp. When I was installing energy management systems (Robertshaw, ISS Clorius, Trend, amongst others) it was standard practice to apply a flow temperature compensation profile between 80C (0C OAT) and 0 (21c OAT) - effectively a straight line between the two end points
I understand that the OpenTherm standard has been corrupted with different firms doing different things probably to keep consumers locked in to their hardware ecosystem. A shame.
Despite its flaws, the Wiser system offers a (tame adjective deleted) of a lot you could only ever get with industrial energy management systems in the 90's and noughties. For the money I think I have got a step change in the controllability of my energy consumption and comfort.
Finally a word of warning. I hadn't clocked that the Wiser 'stat initiated the boiler at 5C (regardless of what you do to configure it, even by nulling the trigger value).
Posted: 2022-12-20 05:26 PM
I'm not really dis'ing the app, I find it easy to use and has all the features that I need (always want more features though! 🙂 ), but Dunxd who started the thread asked about where the temperature data was sourced from and I'm echoing his question as it seems completely detached from the UK weather.
It would seem quite a basic element to acquire reasonably accurate temperature data for a location, PhilHornby can see Lat and Long data in the API. Most other apps I have that display temperature data can get it right for my location, why not Drayton?
Perhaps I'm expecting too much from opentherm, the Wiser system is certainly using it, and reasonably well, I just wasn't expecting a flow temp at 80 for a 4 or 5 degree outside temperature, and also before that when the outside temperature was +10.
I think it's something a lot of the opentherm implementations use to get a fast initial warm up, and then throttle back when approaching set point, to achieve proportional control.
Opentherm has been corrupted as you say, Honeywell's initial idea was a completely open system but various boiler manufacturers have added and changed things to suit themselves. However I think the basics are still there and provide adequate control for comfort and economy.
I think the Wiser system has a lot to offer as long as they continue to develop it and move forward. At the moment it's working well for me and I like the concept, I'm looking forward to the developers implementing some of the main user suggestions such as geofencing and/or auto off for away mode, dark theme etc..
Exciting times ahead I hope.