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.

Summer Project - replacing return piping

NYtimebomb Member Posts: 30
edited May 2022 in Strictly Steam
My first season with the steam system is now over. She dutifully did her job but not without issue.
Over the winter I noticed the LWCO would trip and initiate the water feed. Good to know it worked, but it really shouldn't be. Not everyday. Discovered some very corroded and leaking wet return.

LWCO tripping more and more, to the point where I'd head down to the basement as soon as I woke up and add some water, but it would still trip in the afternoon. Not good.
So here's the section that I will be replacing.

Now to the fun stuff. I blew-down and drained the system today. Lovely browns and blacks.
There really isn't much dry return in the basement, maybe 12-15 ft. total. Wet return is 3-4x that (thus the issue).
So that makes me think I should try to convert the section I am replacing into a dry return by pitching it as much as possible.
One concern is the ancient, indirect radiator hanging from the ceiling. It kind of seems like its resting on the return. If that thing comes crashing down though...
The other concern is the 90 degree turn it has to make. I'd prefer to continue the pitch around the corner to shorten the wet return more.
Thoughts / suggestions?


  • Jamie Hall
    Jamie Hall Member Posts: 22,878
    I'd be very cautious about making it dry. You have several drips that I can see, and chances are they are meant to be isolated from each other. A wet return does that. A dry wouldn't.

    I'd just replace the whole thing, like for like.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • SteamingatMohawk
    SteamingatMohawk Member Posts: 977
    If your dry returns connect above the waterline and there are nearby vents, there could be competition between the returns for which return uses which vent. I had a problem where the returns connected within a foot of each other about 5 feet above the floor. There are vents on each return, but it turned out the shorter return was using the longer return venting to some extent as well, making it take more time for the longer return to completely vent.

    After rerouting the shorter return to below the water line, it was amazing how much better the system works. I can provide before and after pics to help understand all this, if it is confusing.

  • mattmia2
    mattmia2 Member Posts: 9,392
    edited May 2022
    It looks like the corrosion is mostly from the outside from the masonry and moisture. I would just cut off that ell where it heads to the wall replace it with a brass tee, replaced the section on the floor with copper maybe held up a little and fo the same at the other end.

    I would replace the ell with a tee so you can put a valve and hose thread or a capped nipple on each end to flush the horizontal section.
  • NYtimebomb
    NYtimebomb Member Posts: 30
    Here is an edited photo for clarification.
    Red: where leaking is present, both straight pipes at the elbow are wet to the touch.
    Blue: dry return / drip from the basement indirect radiator.
    Purple: dry return / drip from the front of house first and second floor radiators (3 total).

    Much of the piping was existing when the newer boiler was installed. The near boiler piping is terrible and is literally described as 'how not to pipe' according to the installation instructions. The hartford loop is too high, the header too low, there is only one takeoff to the main that goes to a T for both mains, the equalizer is before the takeoff, there are parallel mains where one goes to nothing (but is still connected to the system). It's kind of insane. So before I tackle any of that I'd like to get this leak cleaned up.

    I get it, but to me it seems like there is room for improvement. Even just getting rid of the parallel piping I think would be an improvement. Alas I am no expert though. This section is as far from the boiler as you can get.

    From what I can tell none of my dry returns connect above the waterline. There is one main vent essentially equidistant from both of the drips highlighted. Pics would help me visualize.

    I highlighted in green the elbow I think you are referring to.

    Thank you all for your input.
  • mattmia2
    mattmia2 Member Posts: 9,392
    That is the elbow I was thinking of.

    You should figure out how the near boiler piping is supposed to work before you try to reengineer anything pre new boiler hack. It may have been one end was supply that went all around the basement and dripped in to the return at he boiler but someone connected both to supply with a new boiler or something like that.
  • pedmec
    pedmec Member Posts: 907
    i wouldn't recommend changing them to a dry return. most of the time the original installers knew what they were doing and they had a reason for doing it that way. from the small looks of the piping coming out of the ceiling hung radiator there is a chance your going to get bit by the infamous "a" dimension.
  • NYtimebomb
    NYtimebomb Member Posts: 30
    edited November 2022
    Figured I'd post some follow up photos.

    As soon as I started working on the piping it cracked in the above places. Since the joints were so old and rusty I ended up cutting to make my life easier. Yum!

    I ended up taking most of the advice and kept the piping pretty much the same. I did not run it all the way to the outer wall though, to try to keep the same thing that happened from re-occurring (corrosion from the outside as Mattmia surmised). I also installed a tee to help with flushing and draining as Mattmia suggested.

    Over a month in to heating season and everything had been running much smoother. No leaks, no LWCO trips, no fresh water pouring in everyday.
    Thanks to everyone for their input.

  • Long Beach Ed
    Long Beach Ed Member Posts: 1,183
    Good work!