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How to replace this pipe on boiler


I have a dunkirk blue circle boiler steam system on natural gas. The pipe you see in the pic leaks at the bend, its a pin hole steam leak and not constant only sometimes. The pipe connects the place where you let out the water to the upper valve of the sight glass (the steam part). How do I go about replacing this pipe (also I see that putty was used on the threads so that may me a pia). Thank you all for looking.

<img src="http://i1185.photobucket.com/albums/z345/Fred_Lopman/c9089103-95c1-44a4-832b-b4d2a5a63974.jpg" width="768" height="1024" alt="" />


  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,849
    It only leaks when the boiler is on?

    You need to order a McDonnell & Miller series 67 upper tube assembly, part # 344100, model # SA66-35.

    Prepare yourself for a little shock: this thing goes for $45-$60, depending on where you find it. Before you go and throw that kind of money at it, is the low water cutoff working properly? Have you been blowing it down every week as directed, and when you do, does it cut out the burners and cut them back in?

    How about your pressuretrol? Is it working? Is the pigtail clear?

    You might be able to replace that tube with a length of type L or type K soft copper tubing. I'm not sure if you need 1/2" or 3/8", but you'll need about a foot and some compression fittings. If you can take it off and take it to a plumbing and heating supply store, they can probably set you up with something.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
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