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buderus modulating alpine

I have a buderus 2107 with the 242 card. Thinking I could modulate my replacement boiler which is a gas alpine 210. with remote firing terminals

There are four terminals 37,38,39 on the the 242 card

36 not used

37 /39 dry contact closure for firing of satge two

38 output signal for modulating burners only

what is other terminal (common?) that is needed to go to Alpine 210 remote firing input. ?

Any other guidance ?

when the 242 is plugged in I can choose 1 stage, two stage or Modualting. I am pretty sure it is possible to do this simply.

I would like to keep the 2107 (was on y oil furance) because it is running a very comfortable mixed constant circualtion zone with the 241 card and i do want to take advantage of the modulation feature of the Alpine 210



  • Tim McElwain
    Tim McElwain Member Posts: 4,556
    I suggest you contact Buderus

    for their take on how their control can apply here. I have contacted Burnham for you and here is their reps answer:



    I tried looking up the manuals for the 2107 and FM242 module and there is nothing , that I can find, that even tells you how the control is even communicating with the modulation. The Sage 2 control based Alpines utilize a 4-20 ma signal from the device controlling it and the MCBA equipped Alpines used a 0-10v dc signal. Even if the FM242 did use a 4-20 ma signal there are several settings that would have to be set up on the 2107 such as Min. Modulation, Ignition delay and others and there is no set value for those due to different algorithms and programming platforms between their control and ours. Installers have had to experiment in the field to find the correct settings on other control devices such as Tekmar and Heat Timer and have had to consult with them to acquire the correct settings. I would have to say that this individual would need to go to Buderus with this as well as we do know the inner workings of their control and its software platform. Also the Sage control will need to have a set of contacts to close to create a heat demand in addition to the 4-20 ma signal and many control devices from others may not provide this simultaneously. He can do what he wants but it will unfortunately have to be experimental on his part.

     Glenn Stanton Manager of Training & Technical DevelopmentU.S. Boiler Co.
  • Pablo22
    Pablo22 Member Posts: 4
    Follow-up info-

    Dear Tim, Glen thanks for your comments. I am comfortable programing the 2107 for the correct modulating parameters, ramp up min, max, etc.

    I did find a diagram (attached ) by Buderus on the wiring but it still is not clear which of their out puts go into Alpine's inputs.

    it is pretty clear that 37 and 39 are the TT closure and that 38 is one side of the Firing rate input put I am still unclear on what is the other side of the firing rate input .

    Is there a way to determine with a electric multimeter ?

    the Tekmars have  + and -   Mili-amp terminals but the Buderus is unclear.

    Buderus tech support seems completely unfamiliar with these functions.


  • Tim McElwain
    Tim McElwain Member Posts: 4,556
    Unless someone else here

    on Heatinghelp has an answer for you, I would have to research for an answer which I am sure you can do. Get in touch with Buderus Engineering which is a step up from Tech Services. What is your location?
  • Pablo22
    Pablo22 Member Posts: 4
    Buderes modualting output-continued

    I am located in Boston. Unfortunately calls to Buderus in NH have not  garnered better information

    Thank you
  • Tim McElwain
    Tim McElwain Member Posts: 4,556
    You might try

    a local Buderus dealer sometimes they are pretty good at setting up wiring sistuations. If I have sometime (I am very busy right now) I will look up what I have on the 2107 and also the Alpine and see if I can come up with an answer. Be patient maybe someone else will chime in here and give you a hand.
  • PeterNH
    PeterNH Member Posts: 88


    This might help


    Strange German electrical notation.

    If i was a betting man, i'd try 39 for the comon/return and as is known 38 for the signal.

    Sorry i don't know that much about these devices.

    However, what i do know about electronics is that,

    0-10v signals and 4-20ma current loops are NOT at all compatible.

  • furnacefigher15
    furnacefigher15 Member Posts: 514
    Not compatable to the best of my knowledge

    When they say 2 stage or modulating buners they are referencing third party power burners ( carlin, riello, powerflame, etc...) like the ones used on commercial gas boilers.

    A typical modulating power burners has a low fire start, then full fire / modulating fire enable.

    If you look at the control card, its just a dry contact point, and the controlled power originates in the burner circuit, not the control card.

    Modulating firing rate controls on power burners are R B W controls that use 24 or 110 volt on standard power burners.

    All you can do with the 2107 is provide on/off switching
  • CMadatMe
    CMadatMe Member Posts: 3,086
    Simple Solution

    Would be to use a Tekmar controlling a 3-way sending info back to the Alpine via 0-10 signal. Boiler will still modulate. Could also just add a Taco I-valve to control the mix circuit and let the boiler do its thing for the high temp needs.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
This discussion has been closed.