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Where to put a drain faucet on the mud leg?

My boiler doesn't seem to have a faucet at the lowest point on the return. It take a long time for the water to come back to the boiler. I can drain the boiler from the faucet on the side of the boiler but I think there may be a lot of crud in the pipes down by the floor.

There's some steel and copper pipe down on the floor or maybe 1/2 - 1 inch above the floor.

I'd like to put a faucet or ball valve down by the floor so I can drain the system at the lowest possible point. I'm thinking I'll see a lot of crud that is slowing the wet return.

Does this make sense? Any ideas what kind of faucet I could put down by the floor? Maybe sweat in a 2inch ball valve and attach a hose fitting to drain out the mud leg?




    EBEBRATT-Ed Member Posts: 13,847
    You have that Cast Iron tee where your two returns tie together before it heads to the boiler. I would take the male adapter and that copper elbow off the CI tee where it heads to the boiler.

    Either put a black nipple (the right length) in that CI tee and then another black tee with a ball valve on the run of the new tee and a copper male adapter heading towards the boiler

    or you can do it in copper, either way
  • JohnBeemer
    JohnBeemer Member Posts: 40
    edited October 2021
    I assume you mean where I have the yellow drawling on the elbow. I could cut out that elbow and unscrew the male fitting from the cast iron. Then add another male copper fitting with a tee. I wish I could use a black nipple but there is no room to spin a black tee on the nipple.

    My only problem would be is if the threads on the cast iron tee are damaged when I remove the copper male.

    Thanks for the reply Ed.


  • JohnBeemer
    JohnBeemer Member Posts: 40
    Is there any reason for this end vertical copper piece with a cap on it? I was thinking about cutting off the 90 at the bottom and sweating on a male coupling that I could screw into a 2 inch ball valve. I wouldn't have to deal with the cast iron tee nor sweat in a new tee and nipple. It seems to be the simplest way to get a valve on the mud leg.

    Any thoughts? Thanks for all the help.

    EBEBRATT-Ed Member Posts: 13,847

    That's fine. I was just trying to get the valve near where everything ties together because that's where things plug up. But just do the best you can.

    The threads in the CI tee are usually fine. CI holds up better than steel pipe
  • JohnBeemer
    JohnBeemer Member Posts: 40
    Ed, thanks for the reply. I was also thinking if I put the ball valve at the end and not in the CI tee, I could easily run a snake up pipe.

    I'm not sure why the installer didn't put a valve on the mud leg. I've seen lots of photos of systems with multiple valves on the mud leg. The boiler works but I think the mud leg is slowing the return of condensate. The house is close to 100 years old and I'm not sure the mud leg has every been cleaned so there's probably lots of crud in the mud leg.

    I'll drain the boiler before I cut into the copper. I'll have my wet vac ready because there's sure to be a mess.

    Thanks again,