What actually is 'weather adaptation'?

Could anybody clarify to me what the weather adaptation feature actually does as I cannot find any information online. I have been advised by tado helpline that it take account of sunshine hours, but it does NOT adjust the flow temperature as a weather compensation function on a condensing boiler would. So, does anybody have any insight into how the accounting for sunshine hours is actually done?

Perhaps this information may be included in literature with a bought product, but I haven't bought the product yet and am considering and trying to understand what it actually does.

I am considering a Viessman Vitodens boiler which advertises compatibility with the 'Viessman tado' and advertises that it has weather compensation functionality with it, but this then been refuted by tado helpline...

Thanks in advance for any insight.



  • I believe if it's sunny outside that tado will not open radiator valves on the assumption that the sunshine coming in through windows will heat the room

    If that's the case, it's rather simplistic as tado doesn't know which way the room faces. South facing rooms will benefit from sunshine but north facing certainly won't!

  • Thank you davidlyall.

    I just received a response from the level 2 technical team from Tado after a few days. In case anyone else is interested, I post it below. Doesn't clarify how tado may or may not know if your home receives sun or not though..

    "Tado uses an PID controller and takes the hours of sunshine into account. This means that we do not directly adjust the maximum flow temperature based on outside temperature. 

    That is why it is not a problem to also keep an outside temperature sensor attached, even when you install tado. "

  • GrayDav4276
    GrayDav4276 ✭✭✭
    edited December 2020

    Or to put it another way "the weather adaption is a 'red herring' and actually does nothing" however it 'appears' to be a 'good selling point'.

    I know......I sound a 'bit' cynical, dont I ??🤔

    But it's up there with .....

    1. Open window detected.....only actually detects a 'significant & sudden' temp drop.

    2. Geofencing......which is virtually a waste of time due to operational functionality.

    3. Air comfort.......needs to be configurable to be useful.

    4. Energy savings.......compared to what.....my use or an 'average' household.

    5. Care and protect.....(see comment below)

    6. Auto assist......nothing more than a sales gimmick.

  • There's a significant BS component to the tado system.
  • I’m a engineer for a boiler manufacturer and can tell you The TADO system uses many of the functions which has been available to us in the Comercial sector for years, so is great TADO and others have brought this to the domestic market.

    In the Comercial sector two common weather functions are weather compensation and weather optimisation.

    Weather optimisation is simple the control decides when to bring the heating on to have the room hot for the time you set. I.e set for 7am the controller may activate the heating at 6.35am. It does this by learning. It remembers how long it took on day one to heat the room and adjusts on day two to improve its accuracy. This is effected by outside temp, previous room temp, radiator temp, and may other factors. TADO has a very good one button feature for this and you need not do anything else.

    Weather compensation the radiator temperatures (controlled by the boiler on domestics) is adjusted to give max efficiency therefore when it is 15C outside your rads can be at 40C to hit room temp, but at 5C outside rads may be at 75C to hit room temp. So you save money and efficiency by not overworking your boiler when in warmer spring autumn months. This is the hard part TADO must be using the PID control for as direct boiler compensation will be done by the boiler and it’s outside sensor or another input to tell it to operate at a flow temp.
  • rafm5
    rafm5 | Moderator

    @GrayDav4276 A picture is worth a thousand words

  • GrayDav4276
    GrayDav4276 ✭✭✭
    edited January 2022

    Hi @Staker78

    I can't work out how long you have had a Tado system (or even, if you have a Tado system)..........but I can say this.......I have not seen any actual realtime evidence that Tado systems actually does this......none at all.

    Why would Tado state the following......"Tado uses an PID controller and takes the hours of sunshine into account. This means that we do not directly adjust the maximum flow temperature based on outside temperature. 

    That is why it is not a problem to also keep an outside temperature sensor attached, even when you install tado. "

    The only reason that I can come up with is that an additional "external temperature sensor" will work with the boiler and the Tado PID algorithm does not affect the boilers operation........I would love to be proved wrong........🤔

  • Hi @GrayDav4276,

    Yes I do have a Tado but this wouldn't make a difference as the tech is not new, and you are not wrong the PID would not effect a on/off boiler temperature but could effect the operation.

    If you have a boiler with on/off control Tado cannot control the boiler output temperature with any outside temperature influence. The wavy lines on the app actually mean nothing in this case one or no wavy lines your boiler is off two or three wavy lines your boiler is on, even though the literature says its the power setting this is not how the on/off will interpret it. I currently use this setup myself with an outside sensor on my boiler which controls the boilers output using weather compensation and a heating curve I set, this flow temperature dictated by the boilers outside sensor is what will be output when the Tado can ONLY say come on or off.

    However this is not saying they have no control with this setup. Tado can use local weather data which is fairly accurate to turn the boiler on or off early or late to meet room temp as it sees room temps rising or falling at any given outside air temp and this will be the PID control, but does not effect the boiler flow temperature.

    Tado can control the output of the boiler directly if you use something like Opentherm or E-bus control if the boiler has it built in (mine does but will the tado set?.....no its very annoying). This on the other hand has a big effect on the boiler as it can give a low medium and high output in combination with the boilers outside sensor and is why I want mine to work.

    Geofencing has been my issue in that this was one reason I got Tado. So to find it was subscription based! to get geofencing with auto assist was a disappointment, when I'm trying to be energy saving I now set manually home or away.

  • My understanding of how Tado controls radiator temperature - shown graphically by the wavy lines - is to adjust the degree of radiator valve opening. I can clearly see on my room temperature charts that the dark grey zones when maybe one wavy line is showing are merely regulating the temperature and keeping the curve more or less level at the desired temperature, whereas the light grey zones show temperature rising more steeper which means the valve is fully open, there is more flow and the radiator is hotter.

    Obviously with the valve fully open and the radiator hotter than when it is partially open, the degree of valve opening functions as a perfectly effective proxy for flow temperature, and merely controlling the boiler and circulating pump (in my case just the pump and zone valves as it is a biomass systems with - in theory - an always hot buffer tank or store of hot water) On or Off is sufficient.

  • Dark grey or Light grey.......It seems to me that you have confused the colours.......