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Viega Advanced Heating Controller?

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JoeDi
JoeDi Member Posts: 45

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: 19,602

    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: 45

    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: 19,602

    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: 26,606

    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