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Buderus Panel Radiator Measurements

152NP Member Posts: 49
Can anyone verify if the advertised lengths of Buderus panel radiators include the projection of the flowsetter valve?

I only have 6 feet of wall to pack in a little over 7,000 BTUs of output, and every inch counts. Ideally, I would like to use a 12" high unit. A 20" may not fit under the windows once I account for the space needed at the bottom for piping.

They also suggest these clearances which further complicates things:

Can you remove the flowsetter valves on these radiators and just screw in a plug? The radiator is on a home run system, there are flow adjusters at the manifold, and I am going to be using a TRV, so I don't think I need it. I know you can just screw a TRV on the flowsetter, but, if I need that extra few inches, I can use a Danfos remote setpoint sensor run to a TRV in the supply line somewhere.

Any advice is appreciated.


  • Paul Pollets
    Paul Pollets Member Posts: 3,656
    The TRV needs to be installed over the flowsetter. A 12x64" #22 has an output of 6800btus @190 degrees. I typically size for 140 degree supply water temps because I'm using a condensing boiler. A 16x64" #22 would have an output of 8600btus
  • If you can find a plug with the same threads, I don't see a problem with capping off that valve.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • Paul Pollets
    Paul Pollets Member Posts: 3,656
    If a plug were installed, the radiator would not have a method of control without the flowsetter modulating the return temperature.
  • 152NP
    152NP Member Posts: 49
    @Alan(CaliforniaRadiant)Forbes and @Paul Pollets Thank you for responding to my post.

    I called Bosch/Buderus technical support, and they said they believed the published measurements were inclusive of the protruding flowsetter valve, and that I could remove the valve if I had another means of controlling the flow, which I do.

    In the end, I wound up ordering Ecostyle brand panel radiators. They are less expensive and have a much greater selection of sizes. I got a 16"H x 56"W that is capable of 7,587 BTU at 180 degree supply and will fit within the problem space with room to spare.

    For what it is worth, I am running a mod-con boiler with outdoor reset, and design temp of 180.

    Regarding my comment about ditching the built in valve and being able to control the radiator with a remote sensor, here is what I did in one of the rooms of my house. I have a remote temperature control hooked up to a TRV valve in the basement mounted to a joist. It works great:

    With the Ecostyle, I have room and will put the TRV control right on the radiator, but will use the kind with a remote temperature sensor as there will be some furnishings in front of it that might prevent it from reading the room temp accurately.

    Thanks again!

  • hot_rod
    hot_rod Member Posts: 21,898
    Some creative connections there :)
    You can get pex compression adapters to clean and cheapen the cost of that creative connection. 1/2" valves would be adequate also.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • 152NP
    152NP Member Posts: 49
    @hot_rod I appreciate your recognizing my creative talent :p That was definitely part of a weekend job where I was determined to get it done with the parts I had available on-hand!