Everyone I know that has a woodburner has one of these. Doesn’t require electricity and achieves the same thing - and also fun. Maybe radiators don’t get hot enough to turn a fan by themselves…
Although I’m a bit frustrated about the temperature inconsistency between the different thermostats, I don’t really care what the temperature is measured at. I ended up adjusting each rooms’ setting up or down depending on whether it felt too cold or warm, which might be as much a function of what people do in each room than an actual celsius figure. It would be great if they were more accurate and consistent, but I don’t feel any regret. Much better than the Nest system I had the last place I lived.
I wonder what people on Hive or Tado forums are frustrated by?
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mine are all fine, what version of the integration are you on?
You can create template sensors that correct data from the temperature attribute for iTRVs.
- unique_id: 'bedroom_itrv_temp'
name: 'Bedroom iTRV Temperature'
unit_of_measurement: '°C'
device_class: 'temperature'
state_class: 'measurement'
state: "{{ state_attr('sensor.wiser_itrv_bedroom_signal', 'temperature') }}"
I shared my charts comparing the readings from iTRVs, Wiser room stats, sonoff temp and humidity sensor and the wiser room calculation, earlier in the thread, but can’t find it on my phone right now.
That’s basically what I have done for all connected thermometers (although I have yet to do so for the Wiser ones), based off a calibrated thermometer. Like you said earlier, I set the room comfort temperature based on how it feels and what is done in there (e.g. my office is 1.5 degrees higher than other rooms as I am mostly sitting down and in there all day during the week), rather than the actual temperature, but it’s nice to know what the actual temperature is too. 
state: "{{ (states('sensor.bathroom_temperature_uncalibrated') | float(0) + 0.4) | round(1, 'even', 0) }}"
iTRVs have very weird way of measuring temperature, I’ve noticed temperature is read differently based on if it demands heat or not - in image you can see temperature is actually still dropping while heating is on
I’ve also experimented with having iTVR next to some thermometers, sometimes temperatures matches, sometimes it doesn’t, as you say you can’t apply offset for iTRVs
I get this when hub disconnects for the short period - all iTRVs report 0% battery and temperature of 5C
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That offset is very much required IMO.
The iTRVs are way out of calibrated temperature in my house, usually reading 1-2C below the actual temperature. It also appears that they do some sort of temperature smoothing.
This is graphed using History Explorer Card in case anyone isn’t aware of it. It’s a useful mix of the built-in History Graph Card and the Mini Graph Card.
The actual/real target temperature I am aiming for in the Living Room is 21.5C.
It’s been between -7C and -3C here for the last couple of days, so the heating has been on in some form almost permanently, with the boiler blipping on and off to satisfy demand.
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I’m seeing something similar in my study although the other way around.
Consistently the iTRV is 2 Deg higher than a second measurement. I’ve not checked other rooms, this is my focus as I’m working from home.
Interestingly when I heat the room with an oil filled radiator the temperatures reach the same value, but when I’m not the room temperature drops but the iTRV doesn’t even if the radiator it is mounted on is off.
Had guests staying over so I’ve put spare room on the same schedule as bedroom - 21C in the evening and 19.5C during night. With these settings bedroom never manages to reach 21C actually, but during the night actual temperature stays between 19C and 19.5C
Different story in spare room - iTRV though it reached 21C when actual temperature was only 18C - very disappointing.
To add insult to injury woke up to hub being stuck with Red light for over 30min and not accessible.
Sonoff temperature sensors are arriving today, so will be employing these to automate and reach actual temperatures.
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I’ve noticed a few of my radiators seem to be well below their setpoint and take ages to warm up when the heating is running - I’m guessing the system probably needs balancing, which is something I might tackle today.
I gather I should be looking for around 12’c drop between the flow and return pipes, but when measuring/balancing how should the wiser iTRVs be set ? - Should I have them all set to boost so everything is fully open ?
Interesting. Where on the radiators are your iTRVs and in what orientation? Mine are at the bottom and they are in horizontal position, rather than the more standard vertical, as my pipes come out of the walls rather than the floor. Just wondering if that makes a difference to the readings, as I suspect in this orientation, they are further from the radiator.
Balancing is a bit of a black art, but I think you optimally want a delta T of 20 (i.e. 20C degree drop) between flow and return. However, you should probably check your boiler manual, as apparently some manufacturers specify the delta T. Generally you want a flow of 60C-65C and a return of 40-45C, for best efficiency. This is for a system boiler where you have a hot water tank. If you have a combi boiler, the lower you can get your flow temperature and still maintain a warm house, the more efficient your boiler will be.
Balancing is done with TRV fully open and heating constantly on - simplest way to achieve is to unscrew iTRVs and click heating button on the hub.
Hi. Would you mind sharing how you are measuring the boiler flow temps?
@robertwigley I like the history explorer graph!
I often build these graphs in grafana, but this is easier and saves me punching out to grafana…
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Mine are at the bottom and vertical so fairly standard.
Over Xmas I’m going to add another sensor next to the TRV and see what happens.
How are people tracking/measuring actual boiler firing times - outside of the Wiser Integration? For example, our conventional system boiler has been firing a lot more recently due to the Frost stat triggering it, as temperatures in the garage where the boiler and frost stat are fitted have plummeted at night time! I’d like to track boiler firing times/durations in addition to the stats provided by the Wiser sensors for heating demand.
I have a feeling someone has mentioned this somewhere in this thread, but after reading the entire thread through multiple times now, it’s getting harder to find what you want at nearly 1700 posts!