Temperature offsets can not be used reliably
Hello,
I installed Tado thermostats in my house and immediately figured that these were reporting current temperatures that were way different from what my wall thermometers were stating.
I have read that the temperature offset parameter can be used to compensate this. However, after setting offsets for each room to match the temperature of of each corresponding connected wall thermometer, I would often witness that, after some time, the offset was no longer good.
Being quite annoyed by this, I have written a python script - using libtado to interface with Tado's API - to measure the temperature of wall thermometers and set the offsets accordingly.
The script runs every 20 minutes and logs the offset that was then set to adjust the thermostat with the thermometers. I was curious to see how much adjustment the Tado thermostats would need over time because I am not convinced that offsets can be set once and for all.
Hereafter is the outcome over a 16 hours long period (midnight until 4pm). And the conclusion is that you can NOT, in most cases, rely on these offsets unless you figure a way to programmatically address them regularly (and my goal while purchasing these expensive Tado devices was to avoid having to fix problems with python scripts). In particular, I have a room where the offset changed with a magnitude of 1.6 celsius degrees, another one with 1.1 (the other ranging from 0.3 to 0.4).
Am I the only one having these sort of issues ? Does anyone have a better idea than buying wall thermostats for each room ? (because I find it awful to have to pay an additional 100€ for each room to get a Tado wall thermometer that embeds probably less than 5€ worth of electronics).
Comments
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We have one room where the Tado TRV is on the flow pipe of a big rad behind the sofa, in the South wing that is only heated during the evening. Using successive approximation, we found it needed a minus 2 deg C offset to match the actual evening room temperature. When the room is unheated during the day, the Tado TRV reports the room colder than actual. Now I know that’s the way it works.
The better answer was to install a wireless room stat. Locating the stat on a colder external wall found that the room overheated slightly. Moving the stat slightly away from the external wall works better. The Tado stat room temperature now matches our digital room stats and the Tado granularity is 0.1 deg C. That was easy, room comfort is better, but cost £60. Overall it’s added about four weeks to our Tado ROI, but we’re still quids in.
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How do you actually figure that you save money ? Using the stats returned by Tado ? Or by doing comparison of gas consumption over comparable external climate with and without Tado ?
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I had -3 degree offset on all my stats for a while. The idea was that they reported the right temp when they were on. And it sort of worked. But they were way off when the rads were off. I just set the offsets all off. Now they report roughly the right temp when rads are off. But of course when the rad is hot then they are pretty much useless. So its a nice idea in principle but does not work.
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So, for short, you have not found any solution :)
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thats been exactly my findings - the temp can either be good when not heating, or good when heating (via changing the offset) but never both.
In my case, I have one room that is -6C offset when heating and -2C when not.
No solution in my case!
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They should sell each radiator valve with a small temp sensor.
Ive had 7 valves for a few years and tried the offset in the room - dinning room which is one open space with two big radiators. Kept having to re set it up and down to match a thermometer in the middle of the room. Tried to offset the others without success. Just bought a tado temp sensor placed in middle of room half way up wall. Renamed the dinning room to living room and it warned me it would be deleted and paired. The temp sensor is now controlling two rads and the room is much warmer. I’m thinking now that I may need more of them to heat the rooms properly. Kitchen runs cold and bathroom warm as that has a towel rail on all the time.
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@jmb77777 … I’d be really interested to see your Python scripts, if you were willing to share them.
I replaced all of my home radiator valves with Tado controllers (8) and have my wireless Tado stat in the kitchen. I’ve place small digital thermometers at appropriate points in each room and I’ve been manually driving the termperature offset. I’ve updated each several times a day for the past week and my home stabilised at a nice temperature.
Last night, however, the outside temperature dropped sharply and the whole system needs recalibration.
My conclusion is that the Tado system can be stabilised if the outside conditions don’t vary. Why machine learning is not being used in the software I don’t know 🤷♂️. It would seem sensible to anticipate the impact that weather has on building.0
