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.

Help Identifying pipe type and how to connect

Candrews1992
Candrews1992 Member Posts: 2
edited October 2021 in THE MAIN WALL
Hello guys! So I’ve done a bit of boilers in all sorts of applications, but I’ve run into something that has me baffled. What I’m seeing on an old house is what looks to be zinc coated steel pipe that has been directly soldered to a copper fitting - the crazy part is I saw this on two separate houses around the same time, so I’m sure there’s something I’m missing here. I’m looking to leave the house loops and reattach to this piping but with dissimilar metal concerns I’m pretty well stumped. I’ve been trying to Google this with no success, so any help would be most appreciated.

Comments

  • Zman
    Zman Member Posts: 7,611
    Got a picture? Can you cut, rethread and install a dialectic?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • NoelAnderson
    NoelAnderson Member Posts: 49
    My parent's house had the same thing, it was built in 1950. I think the tube was called Bundy tube. Their house was ahead of the time in design. The boiler system used American Standard convectors that were 10" high with a 1" diameter copper tube. They used a manifold home run system, common today, but not in 1950. The Bundy tubing was 3/8" diameter for the most part with some 1/2" diameter for some larger load areas. The tubing was imbedded in the concrete for the slab on grade lower zone and the 7" thick basement ceiling for the upper zone which was 2' above grade. In the basement above the boiler was four manifolds made from 2" black pipe with globe valves for balancing of the two pumped zones.
  • NoelAnderson
    NoelAnderson Member Posts: 49
    The tubing was nominal copper O.D. tube diameter, and when I had to connect to it, I just sweated on copper fittings.
  • NoelAnderson
    NoelAnderson Member Posts: 49
    I remembered this link when it was originally posted some time ago. https://forum.heatinghelp.com/discussion/comment/828244#Comment_828244
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,507
    They used to make fittings you could sweat onto a brass pipe when switching over to copper. You wouldn't be able to sweat those to steel unless you silver solder it
  • mattmia2
    mattmia2 Member Posts: 10,958
    EBEBRATT-Ed said:

    They used to make fittings you could sweat onto a brass pipe when switching over to copper. You wouldn't be able to sweat those to steel unless you silver solder it

    I thought you could do it with the right flux. i always just filed the zinc off and used rosin flux but I was never soldering to galvanized steel for plumbing.

    According to wikipedia, bundy tubing is the standard steel tubing they use on cars and such for fuel and brake lines and it has an inner copper cladding. I suspect if you can solder to it easily that it is tin or lead plated rather than galvanized.
  • NoelAnderson
    NoelAnderson Member Posts: 49
    The 3/8" and 1/2" tube I sweated to in 1996 held up fine for a couple of years when it failed elsewhere and I had to abandoned the system. The only thing I used was some emery cloth and Oatey brand flux and solder that I bought from Lowes and I used a propane torch to heat it.

Categories