Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

ultra + lwco

joe_140
joe_140 Member Posts: 2
in THE MAIN WALL
wire a MM Guard Dog LWCO to a series 2 Weil McLain Ultra 155?

Comments

  • Mark Custis
    Mark Custis Member Posts: 537
    What do you want to do?

  • Mark Custis
    Mark Custis Member Posts: 537
    What do you want to do?

    Bring on an autofill and shut down the burner?
  • joe_140
    joe_140 Member Posts: 2


    Just to shut down the burner. Seems easy enough with the low volt terminal strip, but it didn't work.
  • Robert O'Connor_12
    Robert O'Connor_12 Member Posts: 728
    joe

    If the LWCO you are working with is a RB-24 the red wire connects to the 24 volt (hot line), the white, to the 24 volt (common), the yellows of the lwco are in series breaking the limit. My suggestion to you is to not use the 24 volt version and use the 110 volt one with the Ultra. The 110 volt one (RB-122) is much simpler to install in this application. If you insist on using the RB-24 be careful, because you can't attach the green (Ground) because that boiler has a secondary ground off the transformer.

    POOF!

    Check with you supplier, I believe MM made a "special" one that you can plug right into the module.

    Robert O'Connor/NJ
This discussion has been closed.

Categories