”Slow start” feature for less thermal stress

Opening the radiator valve fully with a cold system might cause unnecessary thermal stress on the system (and noise due to thermal expansion). Ramping up the valve for a short time might reduce the stress.

I suggest a feature in line with “early start” called “slow start” to automatically ramp up the opening of the valve for cold systems.
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  • Schippie
    Schippie ✭✭✭
    edited January 2021

    Exactly. Extending this, I put in a feature request to control at least the following basic parameters:

    • Maximum early start (determining how early heating may start relative to the desired time at which a certain temperature should be reached
    • Power profile when heating (determining a slow, normal or fast ramp-up of heating power) and cooling
    • Maximum water temperature for heating (so you can maximize at say 60 degrees, preventing overheating at non-tado controlled radiators & pipe noises when adjusting to the high temperature
  • taco
    I would like to be able to reduce the maximum heating power. It will take longer to heat up the house but I expect it to use less gas.
  • Grobsnelf
    I think this suggestion could solve the problem:
  • gary333
    With regards to water temperature it’s worth checking if the boiler can override Tado as an interim measure.

    For example my boiler (Vaillant 938) won’t allow Tado to exceed the temperature set for the central heating within its own settings. I’ve got mine set to 60oC and then when Tado requests 75oC the boiler will only output up to 60oC
  • Schippie
    Sadly, @gary333 my boiler dates from a time where the manufacturer moved all parametrisation to a same-brand thermostat. So nothing I can adapt outside of tado at all. Which is why I am happy tado are thinking of offering more control to end users.
  • Pum
    Pum ✭✭
    I suppose that the issue in this thread could be lifted to a higher level and taken care with the general overhaul of the control strategy that @Jurian mentions in thread posted by @Grobsnelf?
  • This would be very good. The radiator wakes my 1 year old daughter, after having switched to tado.

  • Gideon2
    Totally agree I would call it “eco mode”, where when turned on it would just slow down the heating process.
  • Kanalje

    +1 this.

    We have several small radiators in our old apartment, and the Tados aggressive heating adjustment means that heatet water exits the radiator before it's cooled down sufficiently.

    This is also the case when heating from lowered night temperature and even sometimes even when Tado adjusts to maintain a steady temperature.

    This inefficient utilization of heat is monitored by my district heating company, that'll fine me, if the overall temperature on returned water is to high, which makes sense.

    Before I handled this manually by adjusting the radiators in small increments. With Tado I'd much prefer the option to wait longer before the room heats up than this.

    "Eco-mode" yes please!

  • GrayDav4276
    GrayDav4276 ✭✭✭
    edited December 2022
    I have reduced the amount of thermal stress by implementing my own version of "Early Start" I don't use the tado° version.
    I have adjusted my schedule times and temperature incremental changes to 1/2 hr and 0.5°......so instead of asking for a "high demand" of (say) 2°... I have set 4 changes of 0.5° for 30mins each.
    Some people will say that this is a bit of a faff......but once it's done.....it's done.
    I have less demands of 3 wavy lines and quieter radiators.
  • andyblac

    @GrayDav4276 I posted about this few days ago in another thread, this is exactly what i do too.

  • DM932187

    @GrayDav4276 I'm assuming you've got tado modulating your boiler for you to reduce thermal shock to the system?

    Mine is instead, relayed up with the Viessmann weather comp, and introducing the V3+ yesterday is revealing all sorts of new challenges with the wavy lines, that on the V1 are only for show and don't actually do anything at all.

    What I've noticed so far, is a tendency for the V3 to call one or two wavies, that results in little more than the heating being held about 0.4C below target. By contrast, the V1 has a +/- 0.1 hysteresis either side of target, so the difference is noticeable with the new stat.

    The Early Start is also pap with the new V3. So far, it only comes on about 30 minutes ahead and with tightly dialled in weather comp, that's never going to hit target. I'm lucky if it's up 0.2C, or ever hit target! I'm sure I could contact tado to adjust my settings, but I'd have to wait until the summer for a response, if at all. Other options would be to adjust the comp curve upwards (less efficient) or not set back (really, really less efficient, in my old house)

    I've run the self-programmed option myself in the past. Worked pretty well, save I used to get some switching on and off on the approach, as I hit the revising targets. That might be preferable though, to the V3's pointless wavy lines.