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Repiping Boiler...

Good morning!

At the end of this heating season I am going to repipe the NBP of my steamer with a drop header.

My Hartford loop looks like it is 2.5" My riser fittings in the boiler are 2"

Should I pipe the risers at 2" and feed them into a 3" drop header then continue into the Hartford Loop with a reducer?


Pipe the 2" risers into a 2.5" drop header and continue on into the loop?


Header pitch...half a bubble to the equalizer or back to the boiler? (I think I know the answer to this one.)

My goal here is the make sure the steam is nice and dry on its way out of the boiler. In addition, previous installer piped the header into a bullhead tee at the end into the equalizer. I am gonna fix that puppy!

Suggestion for sealant on the threads?

Thanks all in advance...

"Hey, it looks good on you though..."


  • gerry gill
    gerry gill Member Posts: 3,077
    the bigger the header

    the better it will work..remember minimum size is just that, minimum..asking what pipe sealant to use is like asking a room full of people what movie they like..usually i like blue monster teflon tape coated in megalock...but i also did my 4'' header with permatex black high temp gasket sealer and nothing else..my partner likes blue monster tape coated in tru-blu sealant..its kind of a whatever works for you type answer..
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

    STEAM DOCTOR Member Posts: 1,927

    Blue monster tape and hi temp caulk. Incredibly easy to screw pipes into fittings. One day went I get the courage I will try to hand tighten. I am close to certain that they wont leak. Good luck
  • ChrisJ
    ChrisJ Member Posts: 15,433
    dope, tape or other

    I used blue monster tape and Megaloc as per Gerry Gill's recommendation on my system however, I went with tape + dope only on fittings I considered questionable like going into 80+ year old fittings with new pipe.

    With new Ward fittings and good cut threads I used only Megaloc dope and had zero leaks. 

    I think what Gerry Gill says is true, every guy has a different preference when it comes to pipe sealent.  What I learned over the past few months is quality threads and tightening pipes enough is far more important.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,849
    Sealant today, skim tomorrow

    There are two advantages to PTFE tape: if the joints don't leak, you'll probably be able to get them apart ten years from now without killing yourself, and tape doesn't end up floating on top of your boiler water causing surging and making it more expensive to produce steam. It also doesn't get your hands messy. Okay, three advantages.

    As for header size, 3" pipe has roughly twice the cross-sectional area of 2" pipe, so 2 2" into 3" gives the same volume per length and the same steam velocity until the first system riser comes off.

    As for header pitch, picture the header in your mind. The boiler risers come up, over and down into the top of the header, one through a reducing elbow, the other through a reducing tee. The header goes through the tee towards the equalizer. All the system risers come off between the tee from the riser and the elbow to the equalizer. The idea is to let all the water--the carryover from the boiler and condensation from the system risers and the header itself--run down the equalizer to the return. If the header was pitched back towards the boiler, it would accumulate at the reducing elbow at the end of the header.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • Steam_Starter
    Steam_Starter Member Posts: 109

    Gerry, BN, Chris;

    Thanks for your input. Guess I am going with a 3" header!

    As for the sealant, I guess everyone has a preference. I will see what my local plumbing shop has on the shelf and run with it.

    Appreciate the insight and BTW- Dan, love this site!

    "Hey, it looks good on you though..."
This discussion has been closed.