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Buderus 2017 on a gas boiler, term 12 needed?

GW
GW Member Posts: 4,302
Does anyone have an idea why the wiring directions show both line voltage and a switched leg going through the 2107? I have a guy calling us where the 12 term died. I fed the Honeywell with live power. The 10-11 are still switching the HW on and off heat call. I couldn't seem to get an answer for the Bud. Thanks, Gary
Gary Wilson
Wilson Services, Inc
Northampton, MA
[email protected]

Comments

  • Ironman
    Ironman Member Posts: 6,555
    edited December 2014
    Terminal 12 is the manual reset high limit. The high voltage terminal (L1) of the aquastat must be fed from that.

    Oil burners – factory jumper between terminals 12 & 10, brings 120V from 12 to 10. When contacts close between terminals 10 & 11, 120V power is sent from terminal 11 to Hot on the burner (terminal 4 is the neutral).

    Gas burners – remove factory installed jumper between terminals 10 & 12. The contacts between terminals 10 & 11 are now “dry” (no voltage present) and switching to the burner is now low voltage between terminals 10 & 11 on the R2107 and TT (or RW) on the boiler aquastat.





    Bob Boan


    Bob Boan
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • GW
    GW Member Posts: 4,302
    Thanks Bob, the HW is the main boiler control, the 2107 is acting as a fuel savings device. I can see the point when the boiler control is removed (on an oil boiler). I'm simply trying to justify 'insisting' the home owner 'must' have a new 2107 installed.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • Ironman
    Ironman Member Posts: 6,555
    Gary,
    The manual reset is under the black cap to the left of the temp dial.
    There's also a fuse under the small cap to the right of the display.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.