I have 2 water lines that I need to get apart, they have a 3/4 galvanized union(female end) threaded on a 3/4 male copper fitting. The pipes are 45 years old not much corrosion. Is it a good idea to heat the fittings first with a torch then get the big wrenches out? Any type of spray first? Thanks for any help. -Ed
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Being an engineer instead of a pipefitter I can't answer exactly what you asked. However, you should not connect ferrous (like iron or galvanized) pipe directly to cuprous (like copper or brass) pipe. Doing so will cause a reaction which accelerates the corrosion of the iron pipe. When you reconnect what you are working on you should replace the union with a dielectric union. One end will thread to the galvanized, the other end will sweat to copper. A dielectric union contains an insulating bushing which prevents electrical contact between the two dissimilar metals, thus significantly reducing corrosion.
Don't heat it. Heat causes expansion and therefore a tighter fit. Instead, use some liquid wrench on the threads. Spray a few times. It will help with the exterior corrosion however little.
Use two wrenches and turn them with equal and opposite force.
So now my question(s): How come? Instead of replacing the union can you replace the galv pipe?
Are you sure this is really 45 years old? Where in the house is it? The best thing for galvanized water pipe is the angle grinder -- you can cut it out fairly quickly, and dumpster it all. Replace it with copper all the way.
-- J.S.
The reason I'm removing it is to replace with all new copper. For some reason the copper water lines run under the basement slab then they attached galvanized pipe to it. Cutting the galvanized pipe is no problem but on the one line the threaded copper fitting is just slightly below the top of the slab. If I can get the galv. union off the the rest will be a breeze. Sounds like I'll give the liquid wrench a try. A few friends said to heat it but I thought that may cause it to expand and get tighter, but then I thought it may soften the hardened pipe dope. -Ed
Heating it up and then letting it cool down would probably help break it; heat the female more than the male side.
The heat will make it all expand but the copper will expand more than the steel. support the piece you wish to save and undo the other. If the fitting is cast iron then use a lump hammer to support the fitting and a good wack on the other side will break it.
ED
Just curious...why don't you go copper all the way? Sweat new elbows or whatever fittings on. Why are you opposed to that....or are you? thats what I'd do.
Be well
Namaste'
Andy
It's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
Just curious as long as we're on the topic. I know a zillion uses for duct tape and WD-40 but what other uses are there for pentrationg lubricants? <G>
Be lubricated woman
Andy <G> PS my wife didnt think this was funny <G>It's not who's right, it's who's left ~ http://CLIFFORDRENOVATIONS.COM
Andy, I use it to spray the inside of my snowblower around the auger and chute so that the snow doesn't clog it up.......works well. -Ed
I believe your weife is thinking up new uses for duct tape right now. Sleep light tonight my man.
;).
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Piff
No wonder my wrists hurt this morning
be a wall
Namaste
AndyYou don’t complete your inner work before you do your outer work. Nor do you say, "Well, the hell with the inner work: I’ll go do the outer work because it’s so important and pressing." That’s not conscious either. The conscious thing is the simultaneous doing of both. "Ram Dass"http://CLIFFORDRENOVATIONS.COM
Here's my two cents ......the best penetrating sprays out there for this are Pipebreak and PB Blaster. Pipebreak is defintiely my favored of the two if you can find it.......but PB Blaster is a good product as well. I'd try to spray that joint at least two hours before you put the wrenches to it.
The local tool shop carries the PB Blaster so I will give that a try. Thanks to everyone for the tips. -Ed
See the "Truck Hitch" thread in General Discussions for a lot of commentary on various penetrating oil products.
-- J.S.
I never needed any more then Liquid Wrench for loosening
galvanized unions. A proper set of pipe wrenches is helpful.
You mention under-slab copper sections....which we also have and I am very concerned with eventual leaks.
Can anyone comment on this ?
I understand copper and concrete isn't a good combination.
Last year I bypassed several under-slab sections of baseboard radiator lines.
1950s vintage house next door has some copper domestic water line sections under-slab.
Alan
Alan,
I've only been in the house for 5 years. The house was built in 1956. All water lines that are copper are under the slab then they attached galvanized to that. There used to be radaint heat in the slab with copper tubing but it failed before I bought the house and was converted over to baseboard. I'm thinking that the domestic water runs under the concrete. I thought that the reason most copper fails in concrete (especailly radiant) is because it's tied to the steel mesh or rebar. -Ed
Ed
There is a well known story about a whole town in NY state (Levittown) where most of the houses built with under slab copper radiant lines sprung leaks.
Our 1950s vintage house was built with convective baseboards (copper pipes) with some of the basement zone runs going under slab. For the under slab runs they used galvanized. Suspecting leaks in two of the three under slab runs, I bypassed them. (There is another run that was bypassed before we bought the house in 1996.)
My very limited understanding with leaky copper is something about the property of concrete that contributes to this over a long period.
Someone else will be able to explain this in-depth.
I am concerned about the under slab copper domestic water lines next door....
Alan
AH
you from Levittown? I'm a half hour north from there and have done losts of work over those slabs
Be well
Namaste'
AndyYou don’t complete your inner work before you do your outer work. Nor do you say, "Well, the hell with the inner work: I’ll go do the outer work because it’s so important and pressing." That’s not conscious either. The conscious thing is the simultaneous doing of both. "Ram Dass"http://CLIFFORDRENOVATIONS.COM
Andy -
Nowhere near it.
I am in southwest Virginia and own three of Dan Holohan's books.
Chapter 4 in "Hydronic Radiant Heating" is 'A place called Levittown'.
Thanks to these books and The Wall, plus Breaktime, I have the smoothest running baseboard hotwater heat/gas boiler in a 1950s vintage brick ranch.
Alan
AH
Well I worked on a lot of Levitown homes. They were built during WWll as affordable homes for GI's. All on slabs. Its still affordable but kinda cramped if ya ask me. zero property.
Be a wall
Namaste
AndyYou don’t complete your inner work before you do your outer work. Nor do you say, "Well, the hell with the inner work: I’ll go do the outer work because it’s so important and pressing." That’s not conscious either. The conscious thing is the simultaneous doing of both. "Ram Dass"http://CLIFFORDRENOVATIONS.COM
Yes, I understand it kept many tradesmen plenty busy.
No vapor barrier under the slab and no perimeter insulation that allowed them to have a garden surrounding the house in the winter.
When I'm near the area I do intend to drive through this neighborhood for sightseeing.
Alan
AH
My hood is worth sightseeing wayyyyyyyy more then Levitown. Call for a tour
Be a wall
Namaste
AndyYou don’t complete your inner work before you do your outer work. Nor do you say, "Well, the hell with the inner work: I’ll go do the outer work because it’s so important and pressing." That’s not conscious either. The conscious thing is the simultaneous doing of both. "Ram Dass"http://CLIFFORDRENOVATIONS.COM
Andy -
Thanks for the offer !
Will be a while before I'm brave enough to travel with three
young boys.
It was back in 1993, pre wife/boys, when I last drove through NY state, on the way to Canada.
Alan
AH
You and your wife and sons are more then welcome to spend a cpl a days here. I just ordered a 20' tipi so if ya want you sure might have some fun and privacy. I have a 12 year old so they might just just have fun. Lots of historic stuff round here and NYC is about 45 min away.
Be a wall
Namaste
AndyYou don’t complete your inner work before you do your outer work. Nor do you say, "Well, the hell with the inner work: I’ll go do the outer work because it’s so important and pressing." That’s not conscious either. The conscious thing is the simultaneous doing of both. "Ram Dass"http://CLIFFORDRENOVATIONS.COM
Use a good penetrating oil, soak the threads good, let it sit 1/2 hr, soak it again.
After a while take a 2# hammer and while backing up the opposite side of the union
tap it good with the hammer while moving around the union. You might have to do
this 4-5 times, just be patient, it should work.
Dick
Copper within the slab is not recommended because it can be corroded. But if it's under the slab and not within it it is likely to be ok.
Copper was used in the 1950s for radiant floor heat because it was the best they had at the time and the long term durability problems were unknown. Now the problems are known and there are proper material (e.g. PEX).
I visited a private residence designed in the 1950s by Frank Lloyd Wright. He used copper radiant floor heat in that home and it is still working without leaks today.
re - I visited a private residence designed in the 1950s by Frank Lloyd Wright. He used copper radiant floor heat
in that home and it is still working without leaks today.
------
I suppose he must have known the proper mix of concrete to prevent such a problem ?
My impression of him is he knew a thing or two about concrete.
(But how about those leaky roofs in some of his famous buildings !)
Alan
This raises a question which I'm curious about. The water service line for my house currently under construction is copper and will be coming up through the basement floor slab, in contact with the concrete. Should I not be putting something such as pipe wrap around the pipe as it passes through the concrete? I'm aware of 50's -era houses in my area (Niagara- Canada) where the copper IFR tubing has eroded from corrosive effects of the concrete. (Probably worse in winter-pours because of extra salts in the admixture.)
What is normally done at this junction?
Thanks - Brian.
Edited 12/6/2002 11:43:30 PM ET by MARKLS8