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McDonnell 67 Boiler Wiring

I stupidly detached my LWCO without taking pictures of what wires were landing where. I have a Mcdonnell 67. There is an autofeeder and the original pressuretrol (American Standard built in 1964). The PO's have the wiring a bit of a mess with an electrical tape and wingnuts in there. I haven't really decifered what they are doing, but I would guess they used the electrical tape to make a jumpered connection like I see on some of the wiring diagrams. I have the auto feeder wired on terminals 3 and 4, and that works properly. I am having trouble understanding how to wire the switches on the lwco and pressuretrol. I think I am just fundamentally not understanding how the switching should be setup as opposed to anything goofy going on. Anyone have any easy to digest diagram/pictures? I have looked at the LWCO wiring diagram and this link http://wea-inc.com/pdf/MMwiring.pdf and understand I need to make a series circuit between the 3 points (lwco, pressuretrol and finally gas valve) but think I am just being especially dense today. I've wired up plenty of switches in my house wiring but for some reason can't wrap my head around this.


  • Empire_2
    Empire_2 Member Posts: 2,343
    edited October 2015
    Any solutions yet? Just wondering..... Steam can cause quick damage to skin if not totally understood! I just want you to be careful and get on site help from professional SteamHead... The Q; is concerning in and of itself...... All due respect.

    Mike T.
  • JStar
    JStar Member Posts: 2,752
    edited October 2015
    When it comes to safety devices, don't guess or try. Either be certain or call a professional.