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Adding Thermostatic Valve Operators to a Roth HK Manifold

Hi! I'll try to explain what I have and what I want to do and see if it all makes sense. Plus I am having trouble sourcing one piece that maybe someone can help with.

I have radiant in-floor heat throughout my South-East Wisconsin two-story home. In my opinion, there is no better way to heat a home, keep the wife happy and keep the heating bill in check than radiant heat. My system features individual Taco circulating pumps supplying Roth HK manifolds for each heating zone (see pictures). My boiler is a 2007 Wiel-McLain which has no trouble keeping up with demand.



All of my second floor bedrooms are fed from the single manifold pictured. The thermostat is in the hallway which is open to the first floor. Each of the four loops run the length of the hall before splitting off to the bedrooms. (How many of you guys are smiling and nodding right now?) The result of course is a nice toasty hallway when the bedroom doors are closed and cold bedrooms.

For all intents and purposes, each individual loop heats one bedroom. I've tried to balance the rooms but when the December winds blow from one direction, one bedroom gets cold and when it blows from the other direction, a different one gets cold. What I want to do is change my system so that each bedroom has it's own thermostat and heat loop.

My plan is to add a Valve Control Module ( and individual thermostats ( to control the Thermostatic Valve Operators. This is where I run into the problem - I'm having trouble sourcing them and I don't know that other brands will fit or can be fitted with adapters.

So, the big question here is does anyone think I'm barking up the wrong tree? The next question is where can I find the Roth 2340055354 Valve Actuator OR can I use something like an Upnor with an adapter ring of some sort. I'm kinda stuck on this project until I get the actuators.



  • JeffM
    JeffM Member Posts: 174
    If you are thinking about Uponor actuators like these
    the manufacturer has a bunch of different adapters available for different manifolds
    You might have to do some work to find a supplier, or try a couple of different ones to get the right fit ( lists a few of the options, but not one for listed Roth manifolds).
  • twobeemers
    twobeemers Member Posts: 5
    I'm finding the same thing, that there aren't many published options for the Roth manifolds. Thanks for the leads, I'll keep looking.
  • twobeemers
    twobeemers Member Posts: 5
    I'm a little hesitant to use an adapter for a couple of different reasons. Not being "in the biz" I don't know how things are measured so it would be a trial-and-error exercise. On top of that, if I were to put an Uponor actuator on top of a Moehlenhoff adapter to a Roth manifold, who's to say they will play nice together in the long run? So I think I'm just going to source the proper Roth actuators and use those. Seems like it will make life easier in the long run.
  • hot_rod
    hot_rod Member Posts: 15,029
    too bad they don't standardize those actuators like they did TRV threads.

    Even if you find another actuator that snaps on, the pin length and stroke don't always match. You could end up with a valve that does not close off completely, of does not open fully.

    Look for the correct Roth part.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • twobeemers
    twobeemers Member Posts: 5
    You hit the nail right on the head, hot rod. Different threads, different pin size/length/stroke - the exact things I was thinking about when I decided just to use the proper Roth parts.
  • castlerock
    castlerock Member Posts: 1
    Twobeemers - i have the same exact issue with my Roth system. Did you find a solution and if so please let me know what you used and where you sourced the actuatots from. Thanks from Vermont
  • njtommy
    njtommy Member Posts: 1,105
    I guess you could get in zone valves on the pex piping it's self.
  • bmwpowere36m3
    bmwpowere36m3 Member Posts: 512
    I've put in a Roth manifold and PEX... all from my local supply house. Call Roth and ask for their distributors in your area.