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Viessmann low loss header substitution

Anyone know where I can get a Viessmann LLH for aWB2B 35?

There are plenty of substitutions out there with an air vent on top or a 1/2" npt that could be used for the header sensor but I am unsure about the well.

Is there a reason the 120/80 will not work? This header is readily available.


  • Paul Pollets
    Paul Pollets Member Posts: 3,656

    Why can't the company that sold the appliance provide one?

    The smallest LLH sold has a max flow of 17gpm.

    If the Caleffi hydraulic separator is used, the sensor can be strapped to the system supply outlet of the device
  • Canecreek
    Canecreek Member Posts: 21
    Viessman LLH

    Thanks Paul,

    I was ableto get a 80/60 ordered this AM with sensor
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