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Viega Advanced Heating Controller?

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JoeDi
JoeDi Member Posts: 54
in Radiant Heating

Hi, I bought this house with 2 Viega heating controllers, controlling mixing valves on 2 different radiant floor manifolds/systems. One is the Viega basic heating controller which has plenty of info online. The other is an "Advanced Heating Controller" which I can not find any info about online at all. Its similar to an advanced snow melt controller they sell but its not the same, and mine clearly is designed for not just snow melt (but seems maybe it can do both snow melt AND indooor radiant heat "mixing reset")

Does anyone have a manual for this?

image.png

As far as the problems. Well as you can see the outdoor sensor is bad. Also, I am not sure its all wired properly because someone scribbled black and red on the connections but the mixing pump runs all the time if those terminals are energized or not.

Also the mixing valve runs way too hot if its positioned in the middle, even though its 32F outside which is what this thing should be defaulting to.

Thanks

Comments

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 19,625

    Looks like a "Tekmar" control made by Watts. Maybe you could check their site. Or call Viega or Watts on Monday.

    In fact I looked closer and it says Tekmar Canada.

    Are you in Canada? Tekmar Controls LTD is in BC, maybe contact them

  • JoeDi
    JoeDi Member Posts: 54
    https://forum.heatinghelp.com/discussion/comment/1879539#Comment_1879539

    Thanks, I am in NJ.

    I believe Tekmar sells their radiant floor systems under the Viega brand name but not 100% sure. I am going to reach out to both Viega and Tekmar on Monday.

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 19,625

    I looked on the Tekmar site but they have a million controls to sort through. Yours says Tektra 928-00. I couldn't find that. Maybe you will have better luck.

    Or you may have a better model #

  • hot_rod
    hot_rod Member Posts: 26,645

    I think tekmar has an OEM division Tektra. They build controls for a number of different brands.

    In some cases they add additional features specific to the customer. I suspect the tekmar manual would be very close for programming. That looks like a Boiler Control

    Looks like the outdoor sensor is bad or the wire or connection is bad "open" #27 & 29 on the terminal strip, put an ohm meter on those wires to troubleshoot. The manual will show the resistance based on temperature at the sensor. I think the control may function if you disconnect the red and white on those terminals.

    Screenshot 2025-12-28 at 11.32.07 AM.png

    Here is the tekmar link, they do have a section with manuals for "legacy" controls

    https://www.watts.com/products/hvac-hot-water-solutions/controls/boiler-and-mixing-controls

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • JoeDi
    JoeDi Member Posts: 54
    https://forum.heatinghelp.com/discussion/comment/1879552#Comment_1879552

    Thanks, I've already disconnected the sensor which to my understanding is supposed to then act like its always 32F outside. It kind of works but i am not sure the mixing valve is working properly, I seem to have to manually adjust it a lot. I think the entire system depends on how much my furnace is running for the forced air systems that are the supplements to the radiant. When they run a lot, the floor gets really waarm because its constantly getting new hot water pushed to it. I think the entire mixing system has issues.

    On my other loop it only sounds like water is moving through it when the main circulator pump is running, so i think the loop pump is broken on that one.

  • hot_rod
    hot_rod Member Posts: 26,645

    Spend some time on a chair in front of the boiler to get some data. Without knowing how it is controlling currently, it is not easy to suggest control manipulations.

    Some strap on temperature gauges and a pad of paper to get some stable temperature data.

    Regardless the outdoor sensor, connections, or wiring should be corrected, it is an important part of the temperature control scheme.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • JoeDi
    JoeDi Member Posts: 54

    Good news, Viega was awesome, super helpful on the phone and sent me the manual for the advanced controller.

    Here it is for anyone else who finds this via google in the future!

    Manual Link: Salesforce

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