Opentherm with Ideal Logic 30 Boiler



  • Packages came quicker than anticipated, so went to work hooking everything up.

    Process was surprisingly straightforward and had everything working in just over an hour.

    I have a question about the hot water aspect of the app though.

    The app shows hot water as on between 0700 and 2200, which I imagine is the default, but as mine is a combi boiler, I can get hot water on demand at any time, if my understanding is right.

    I also have the option to switch off the hot water in the app. Again, I didn't think I had any direct control of the HW on a combi other than setting the temperature.

    Correct me if I'm wrong as it won't be the first time!

    @tadouser1000 @NeonDusk

  • tadouser1000
    tadouser1000 ✭✭
    edited November 2021
    @Blootoon that's great! Glad you got it all working.

    I don't have hot water control because I think I initiated the install with a relay based Logic boiler and asked Tado to enable Opentherm manually so hence I don't get hot water control.

    I believe hot water control turns hot water pre heat on and off. This is where the boiler fires up periodically to heat a small tank of water so you have instant hot water without having to wait a few seconds for the water to heat up. I've not used hot water pre heat or hot water control but this is my vague understanding
  • Hi All.

    Just a quick question... is there say way to tell from my boiler (or the app) if my extension kit has been wired up to allow OpenTherm? Or could I only confirm by looking at the actual wiring?

    It was installed last year and I wasn't even aware, until I stumbled upon this thread, that my boiler was modulating. This is a bonus... I just hope my Tado has been making use of it!

  • @nick6young only sure way to tell is to check the wiring.

    You could request a small amount of heat (0.5 degree) from one of your thermostats and check the flow temperature on the boiler. If it doesn't reach max flow temperature for small heat demand that means it's modulating using Opentherm

    If the flow temperature reaches max every time (even for small heat demand) then it's wired using relay
  • nick6young
    edited January 12
    Thank for the response.

    I've been keeping an eye on it and it seems to always crank up to 69 degrees every time. Which I believe is the max. I haven't seen it heating lower than that.

    Having said that though... on my heat graph in the Tado app... when there is a dark grey zone, the heat ramps up rapidly. When it is the lightest grey... it seems to maintain the temp. Which leads me to believe it is indeed modulating.

    I was hoping to post a screenshot to better explain what I mean, but there doesn't seem to be the option... so hopefully that description does a good enough job, ha!
  • @nick6young yes I think I know what you mean. If the boiler is still going to max even during the light grey bit (usually when you see one wavy line) it suggests relay mode
  • I managed to install Opentherm on my logic 30. I didn’t need a harness, support told me I did. I think there is an older version of logic 30 main board that requires an harness. Anyway mine came with Opentherm and weather comp ready and I followed the logic + instructions. The only difference on mine is that I left the loop on thermostat connection. I saw it on Alan harts YouTube channel. After a day of messing about, it’s finally working, phew