Pre and post installation Q

Before installing the wireless sensor and smart TRV my boiler used to heat up to 60 very aggressively and all radiators would feel HOT until the manual TRVs felt the room temp was adequate and then they would close off.

As a test today I have opened all the rads in the house to 3 / 6 (manual TRVS), have turned on the SMART TRV in the living room and the boiler fires very very slowly up to about 45 deg (on the digital water return readout) then turns off. The living room TRV is not coming up to temperature and all the radiators feel only moderately warm eg probably only 45 deg.

I have even offset the smart valve to 1.5deg because it was reading 21 deg when the room temp was in fact 19.5

Q: Should TADO not be calling for much hotter water to get the temp up quicker? They state they can make boilers call for water up to 80 degrees.

I understand that the water temp might take a while to come up to correct as they other 5 rads will be using the hot water too so perhaps having the manual rads open is allowing the water to exand and cool too much?

PS Boost heating makes no difference.

Best Answers

  • johnnyp78
    johnnyp78 ✭✭✭
    Answer ✓
    It’s much more efficient. The most efficient way would be to remove the Tado altogether, set the weather compensation curve and leave it. If you want to keep using Tado, set the temperatures to ones you feel comfortable with and unplug the weather compensation. You shouldn’t need to set early start if your radiators are reasonably efficient. You should also get used to not having boiling hot radiators with a modulating system- they should be on for longer periods at a lower temperature.
  • GrayDav4276
    GrayDav4276 ✭✭✭
    edited January 2023 Answer ✓
    With regards to tado and WC

    Tado gets weather information...... BUT....
    I've seen no evidence of tado "using" the data to control the boiler operation.....all I can "see" is the temperature on the room graphs. There is no obvious correlation of the data actually doing anything.
    It's my honest opinion that this "feature" is no more than a sales gimmick.
  • johnnyp78
    johnnyp78 ✭✭✭
    Answer ✓
    I don’t understand your last paragraph but yes, it’s more efficient to keep to a lower st back temperature then raise a couple of degrees during the day.
  • johnnyp78
    johnnyp78 ✭✭✭
    Answer ✓
    Instructions here in the first post


  • johnnyp78
    johnnyp78 ✭✭✭
    edited January 2023
    How is your wireless receiver installed? Via relay or with a digital (opentherm/ebus) connection? Do you have weather compensation fitted as well?
  • hipponax1973
    edited January 2023
    digital, and weather compensation too. Just feels slow getting up to heat. 38 mins to bring room temp up
    from 19-20.3 degrees. Thought
    boost would draw hotter water.
  • If you’re using Tado on a digital connection it will be clashing with the weather compensation anyway. Sounds like the wc is overriding it. I would pick one or the other. Weather compensation is set and forget, where you leave the boiler on a low and slow setting and it maintains a constant comfort temperature, which it sounds like your system is trying to do.
  • ah
    ok! yes the weather is pretty warm(9deg) but it’s an old fashioned victorian flat with thick walls so feels pretty cold. Is there a simple way to cancel the weather correction or am i defeating the object of tado anyway?
  • Montage
    Montage ✭✭✭

    Sounds like you just need an on/off switch.

  • You could install the Tado on relay, otherwise I think with wc you just disconnect the sensor but don’t know for sure.
  • Montage
    Montage ✭✭✭

    The trouble with that, IMO, is TPI. It'll just keep switching the boiler off to tame the flow temps.

    For the old skool burning hot rads, you can't beat a non-TPI stat :-)

  • Ah yes, @hipponax1973 you’re not going to get the boiler behaving like it did before even without wc. Tado will still cycle the boiler or cut the max flow temp to avoid overshooting.
  • is it more efficient however? if so can set the come on times earlier
  • perhaps we are at cross purposes here… the boilers too old to have a weather sensor-the only place it gets any weather info is from the tado….
  • So you don’t have weather compensation fitted? Tado doesn’t do local weather compensation, perhaps that’s what’s confusing you. Using weather data isn’t the same as weather compensation.

    In that case try turning up the max flow temp on the Tado pro app. It might be that it doesn’t need to heat the radiators very much to reach target temperature though, that’s how a modulating system is supposed to work.
  • ive gone through everything on the pro app and can't find anything that allows me to change my max flow temp - is there another subsetting?

    Ideally id like the radiators to come on full blast for 30 mins before we get up so that bathroom and kitchen are are 20 deg and then peter out to normality - what happened today though was they came one from 15 deg to 19 degrees but it took 90 mins..... perhaps its more efficient to have everything at 18deg overnight then there's little to come up to in heat?

    To complicate it im only using the room sensor in one half of the house and the smart valve in the other in the two spots its useful to keep the temp up.

  • thanks johnnyp78

    Q for you - where in the pro app can I tweak the max flow temp?

  • So interestingly the boiler is not Opentherm compatible but works happily with the EMS Bus that Buderus use - it states on the pro app EMS settings that the boiler maximum flow temp settings should be set manually on the boiler. I confirmed this was the case by attempting to set the max flow temp for the boiler to 30deg through the apps Opentherm Protocol and instead it went off the manual control on the boiler.

    there ARE some ARDUINO protocols out there that can override any boiler settings and allow them to speak to Opentherm however and ill post this in another discussion for people to have ideas.