Has anyone else noticed their TRV’s under reading the current room temp?
One is currently saying it’s 23.2 degrees where as a few other temp sensors in the room are saying it’s 28.8 degrees.
It’s currently 32 degrees outside.
The Wiser TRV’s are not good at measuring the room temp. There is an algorithm that is used to provide a guestimate of the temp but IME its not that acurate.
IME, they typically read 1 to 2 degrees high.
(Providing an energy saving on a setpoint temperature 
Can you place one of the ‘other’ devices in close proximity to the rad stat, to compare?
There can be a significant temperature difference in a room from floor to ceiling level.
I put the temp sensor on top of the TRV!
Ok.
So maybe not all read 1 to 2 degrees high then.
I can’t check with mine at the mo, 'cos I’ve removed the batteries for summer.
(I’m not a really tight git, but they only seem to last 12 months if they only do winter duty).
IME the TRV’s tend to read approx 2 degrees c too high when the heating is on and 2 degrees c too low when the heating is off.
In my experience, the TRVs are certainly not giving accurate temperature readings - how can they be when they are sat on a pipe that varies between cold and boiling hot? - BUT they are pretty good at estimating the overall room temp consistently, whether the heating is on or not, so I just regard what they report as “a number”, and set the target “number” according to what I feel is needed for that room. If I set a bedroom to 18 for example, it always reaches the same comfortable temp that I want. If you really need to know what the accurate temperature reading in a room is, you need a separate sensor (be that a wiser room stat or whatever). If you are happy just knowing “if I set that TRV to 18, it always feels ok in there” then they work really well. In our main living room there are 2 TRVs AND a room stat that controls them, and that setup works well too, but the wiser room stats are too ridiculously overpriced to have them everywhere there’s a TRV.
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That’s the approach I take too - I have the Wiser room stat that came with the hub kit in my living room. I then purchased a bunch of £11 Sonoff SNZB-02 temp and humidity sensors and put them in rooms I most care about.
I made some template sensors that record the difference between the Sonoff sensor’s temp measurement and the iTRV in that room. That shows around a 1 degree difference when the heating is off and a 2 degree difference when the heating is on (I’ll share graphs when I have a bit more data). These show similar results to the difference between the one roomstat I have and the iTRV measurements in the Living Room. The only difference is that the Sonoff’s can’t tell the Wiser Hub what they measured.
I set the coldest rooms 3 degrees higher than what I really want in Wiser, and the other rooms 2 degrees higher, and this usually makes the rooms comfortable in winter. In the summer I just put all the rooms onto a summer schedule with a lower temp setting.
It is frustrating that Wiser have priced themselves out of this - they really should offer a cheap, display free sensor similar in price and functionality to the Sonoff SZNB-02.
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Agree, over time though Ive acquired/bought cheap room stats for the bedrooms. For the other rooms, I know what the delta typically is and just set the heating to that. E.g. my sons room is always warm, so I set it the trv to 19c, but its more like 21. and so on…
Before wiser i had the Max! valves (they were terrible!) but they did allow you to add a compensanting temp , +/- up to 5C. which was useful…
@msp1974 Mark , didnt you find some EU room stats that appeared to work with Wiser?
In France, Schneider sell a new stat cost effective https://www.se.com/fr/fr/product/CCT593012/wiser-détecteur-de-température-et-dhumidité/ compatible with the second generation hub…
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…and recently they have started dropping offline again…
Not here, rock solid.
Probably your environment 
A couple of my TRVs started dropping off a few days ago too. I have one that keeps dropping off, and also refuses to connect to a plug that is literally 2 feet from it (which other TRVs in other rooms connect to fine), it insists on connecting to another plug that is downstairs from it, and reports poor signal when it is connected. Battery showing 100%. Before this everything was solid.
I don’t know that it is worth worrying too much about signal strength or ZigBee topology. Even if the signal is weak the tiny level of traffic will likely still get through successfully enough for the functionality to work. It isn’t like we are streaming movies to our iTRVs where speed or packet drops would be noticeable.
As long as your TRVs are connected at all and most of the time then the radiators can open and close their valves. Is a connection required for the valves to open/close or does the iTRV decide itself based on the current target temperature? The communication may just tell the iTRV that the target temperature changed and in the other direction it is reporting the current temp to the hub every so often.
Millisecond reliable connectivity isn’t needed.As long as data is transferred successfully every few minutes I would imagine everything is working acceptably.
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Another Wiser Home app release (6.11.2) and yet again zero info on what the release fixes, enhances or adds.
Tis the wiser way im afraid, they do sometimes tell us whats new…
They clearly haven’t done anything about the STUPID screen sliding info left / right, when selecting a day in the schedule view.
(Introduced around 3 or 4 versions ago).
Enhancements should be improvements in visibility, clarity, reliability and function.
That one was clearly a gimmic which now makes spotting differences in day to day times or temperatures impossible.
Perhaps it saved them money somehow?
The only way to compare now for many people, is to write every days temperature & time down.
Crazy!
Fortunately, I still have V 6.1.5 running on my phone, which I can use if necessary.
I have made a number of requests to Schneider for what i see as improvements to the app some of which i have seen requested by others but none have been implemented. Schnieder are clearly not user focused, not in the UK anyway.
I understand your beef with the app, but fortunately we don’t really need it other than for adding new devices. You can use this integrations schedule card in HA to view and adjust your schedules. I barely ever go into the native app and do everything through HA. The schedule card has always been far easier to use than the app for adjusting schedules IMO.
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For those having connectivity issue within the wiser zigbee network:
The attributes of the devices signal entity, shows if its using a repeater - and the channel used. Great help in keeping those separated networks distant to each other and your wifi.