What TRV do I have?

Looking at getting a Tado smart heating system, but after speaking to their support it seems the TRV's I have are not compatible, so does anyone have idea on what ones they are? The brand written on the housing is 'Boss' but would like to know what the actual valves are to see if I can get any adapters for them.

Attached are some photos of the TRV.

Thanks 😊


  • Seems like I have Pegler Yorkshire type TRV which is not compatible at all with Tado, as the below is taken from the documentation on which TRV are compatible 😔

  • They look like the same valves I have (Pegler Terriers), and the Tado heads work fine for me

  • Same here, I have a couple of Mistrals and the Tado heads fit fine . . .

  • Thank you both for the comments and reassurance on that it should work. Oddly enough, I found an older compatibility document for Tado and it said it did fit the same style, but not a different type of pegler style TRV. Go figure 🤷🏻‍♂️
  • danilojose
    edited January 2022
    I think I have the same as you in all the house :( and I bought several Tado valves…

    I think I have pegler terrier iii

    What have you done? I also found out that it does not seem to be any adaptor at the moment…

    I also found the old document that it says it is compatible… after trying for a while I managed to fit it with no adapter but I am not sure if it worked because the radiator was already slightly warm when using it.

    Will they get any adaptor in the future?
  • Hey @danilojose,

    The valves work fine with those TRV's and are working just fine for me. Thanks to the 2 other posted on this thread confirmed it and took the plunge with mine.

    I have also mailed tado support this, as they have 2 documents that contradict each other. The main website shows it as not compatible:

    Whereas I found an older document that says it does work with them:

    Hope that helps clears things up for you 😊

  • I emailed Tado regarding this also and they said it doesn't work lol so im really confused - Im guessing its the 'wide touch' element of native to the Terrier valve.

    For those who have it working, is it working flawlessly or are there issues at all?

    Im just a bit confused why it apparently used to be compatible but no longer isn't? Ive asked Tado for clarification but not had a response back.

  • It's all working fine for me and has done so for the past 3.5 months of using it.

    I did ask tado to update their documents regarding this, but seems they've chosen to ignore it and potentially loosing out on sales because of it 🤷🏻‍♂️
  • Good to know! Definitely losing out on sales, i almost opted for a another system due to this, I think ill take the plunge and give it a try and see how it goes! Thanks for the response again!
  • Any update on this? I have several terrier I valves!
  • Correction: Terrier ii rather
  • @Tomfoolery what do you need to know? The TRVs worked fine on Terrier 2 as long they look like the photos I've posted
  • I am confused by the newer document from Tado ruling it out :/

    Any idea why they originally said it works with no adaptor and now are saying it doesn’t? The valve’s definitely have Terrier ii on them and probably date to the early 2000s if I had to guess.
  • I couldn't tell you, but I've been running mine since Jan and never had an issue
  • Honeywell used to say the Pegler valves will cause their Evohome TRV's to eat through batteries much quicker due to the pins needing a lot more force to close. I presume this will be the same with Tado too. In which case, keep an eye on how long they last as you might find it cheaper to move to a different brand of radiator valves in the long run.

  • I have some peglar bulldog heads with the same valve body and they will not work with tado smart valves and support have informed me of this too… I just get E4 errors all the time.
  • chicsh
    edited February 2023

    Hi all,

    for thise who have replaced the Pegler Terrier II valves with the Tado heads

    Please may i ask if anyone has encountered any issues with the TRV's eating batteries? or any issues with the Tado Heads opening and closing the valves.

    I have around 10 radiators with Pegler Terrier II valves and wish to intall and use the Tado TRV v3s system, but have been put off by support saying the TRV's are not compatable.

    Any Help and advice really appriciated.


  • Been using mine for a year now (as I'm the one that started the topic) and no issues with batteries and still on the same ones. I've been using the smart TRVs on 3 radiators and not had any issues with opening / closing the valves
  • Begbie,

    Thanks for confirming and replying so promptly.

    Excellent news that the TRVs are working with no issues.

  • Thank you for finding old doc, I was pretty sure I saw them at some point as compatible, but it didn't work properly on mine, so had to return them. I thought I was going crazy, but now all makes sense.