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Smart TRVs

maineguymaineguy Posts: 5Member
I recently moved into an older house that has radiators in each room controlled by a TRV. The heating system is natural gas fueled and is fairly new having been installed in the last couple years -- my area has only recently had natural gas introduced. However, it's been quite an adjustment having to control the heat on each individual radiator after having an Ecobee thermostat with the oil system at my old house, and before that just a simple programmable thermostat to set the heat down at night, and bring it up in the morning. Even the initial adjustment to knowing what "3" even means on the TRVs has been a fun new experience.

Does anyone know of any systems sold in the US that can be used so I can program a schedule for the radiatiors, or better yet, would allow for some remote control, say from an app. I see a lot of european options (like the Danfoss LC13 or the Eve Themro), but almost every TRV I see sold in the states is what I will call bare-bones manual. It appears that Oventrop may sell their R-Tronic units in the states -- but I can't find where to order or even check prices on those. Anyway, thanks for any leads.



  • mars_6mars_6 Posts: 104Member
    I belive I saw a Honeywell digital trv at my wholesale P and H house in Denver that was programmable. Might check that out.
    Matt Rossi
  • maineguymaineguy Posts: 5Member
    Thanks. I'll check it out -- initially surprised at how expensive the honeywell units are. And I can only seem to find them available on eBay.

    Are there any online sites that specialize in parts like this? I find it odd, that you can buy programmable themostats all of the place, but these parts seem so elusive, even online.
  • Danny ScullyDanny Scully Posts: 1,170Member
    @maineguy, trvs control the radiator, not the boiler. In theory you should still be able to have the Ecobee you described. Tell us more about your system. Pictures even. Is it steam or hot water?
  • maineguymaineguy Posts: 5Member
    edited January 14
    @Danny Scully It's hot water. I have a boiler downstairs, but there is no thermostat in the house, which is why I don't believe I can have a system like the ecobee. My understanding is the the boiler keeps a loop of water heated (during summer months, it shuts off based on an digital thermometer that is mounted outside) and as the individual radiators call for heat, the water gets looped into that system; each radiator has an in and a return pipe. (This is my layman's understanding from how the person who serviced the boiler described it.) The hot water system is separate.

    Sorry for the poor quality, I can get a better one if needed, but this is the boiler setup:

    So to control the heat of an individual room, we turn the TRV (or is it the actuator?) to a setting from 1-6, and my understanding is that based on temperature it will open to allow the hot water through. My problem is turning it up in the morning, as we're getting ready for work and then forgetting to turn it down before we leave for the day.
  • Danny ScullyDanny Scully Posts: 1,170Member
    It sounds more like it’s running based on outdoor reset. The trvs don’t start or stop the boiler, they just control the emitter temp. You should be able to change the control strategy to allow for a thermostat, although it was likely designed to work off outdoor reset. Maybe that just needs to be adjusted properly. Where are you located?
  • maineguymaineguy Posts: 5Member
    edited January 14
    @Danny Scully I'm in Bangor, Maine. Right, yeah the boiler essentially is on the all of the time from what I understand to keep the loop heated (except in summer). And it's just how "open" the individual TRVs are as to how much they heat.

    I'm not sure how the outdoor reset would allow us to control room temperature based on our schedules, but I'm willing to look into seeing whether it needs to be adjusted.

    Also, I know the last tech to service the system seemed skeptical about a thermostat solution when I brought it up, which is why I was looking for programmable/smart TRVs; and I'm not sure how we would zone that through the different areas of the house.
  • Frank_DobbsFrank_Dobbs Posts: 3Member
    I was just going to post on this question.

    It just seems to me that smart electronic TRV's are a good idea and the wave of the future. I control my doorbell, lock, shades, stereo, TV, lighting, shower/bath, minisplits, towel warmer, air purifier, electronic subfloor bath heating and someday real soon perhaps my Viessmann remotely. So why not my TRV's.

    My wife has retired recently, and she was just grilling me about why the TRV's do not have digital readouts, and all I could say is I thought about that originally, but finally just accepted that as the way things are done. But man I really like that I can control my shower volume and temp precisely each and every time. And even if I would not change the settings on the TRV's, I could use the smartphone to see whether all radiators are operating properly and are properly balanced. What's not to like.

    One thing not to like is that the Danfoss tech uses bluetooth instead of wifi, so the range is limited.

    I know that when I wanted to convert my analog Dornbracht shower control to digital that they have wondertful electronic tech in Europe. I found a video where the chairman of Dornbracht promised that this same tech would be sold in the US. But that promise was not kept. So I wound up buying a system from Moen.

    Is this tech available in the US, or is this another case where Europe gets the good stuff and we are the poor little boys looking at the candy store window from outside?

  • maineguymaineguy Posts: 5Member
    Yes, that is the crux of my question -- is that technology available in the US? And from where? A search of say, for "smart radiator valve" turns up a bunch. several very affordable, while basically nada on
  • Jamie HallJamie Hall Posts: 10,401Member
    There is no particular reason why you can't import them yourself, together with the valve body and a converter to power them. Not inexpensive, but if it's what you want...

    It is not a conspiracy that such gadgets -- along with a lot of other glitter -- are not available in the US or Canada. It's pure economics -- the market simply isn't there. Perhaps some day it will be, but for the time being most people with hot water heat get by with multiple zones -- which can each have their own wifi thermostat, of course -- rather than microzoning through TRVs.

    As to having everything in one's house connected to the internet, and hence publicly available (don't kid yourself -- if it's hooked up to the net, it's public), that's another and quite debatable matter.

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • Frank_DobbsFrank_Dobbs Posts: 3Member
    edited January 16
    Duplicate deleted
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