Right way to disassemble radiator piping?

Question

I have an old house with a radiator system, and am needing to take a radiator out. While some of the radiators in my house have nuts on both ends of the radiator, making it easy to remove, this one only has a nut on one end. On the other end is a straight pipe coming out of the radiator, which threads into a 90-degree elbow, and so on.

There's so much paint on the pipe that I can't tell whether the end connecting to the radiator is threaded or whether it's a part of the radiator itself. Thinking it was likely threaded, I tried holding the elbow still while cranking on the pipe, but it wouldn't budge. Before I get out the sawzall or crank more on the pipe, I thought I'd get others' thoughts on what the right way of going about this is.

Is there a way to disconnect the pipe from the radiator? If I used a sawzall, am I ruining a part of the radiator itself? Or could I sawzall it and somehow get the ends of the cut pipe out of the radiator and the elbow, and then replace the pipe w/a better solution that has a nut? I need to be able to re-install the radiator later in the same location.

Answer 1

What I would do:

Cut the long pipe. Move the radiator, making both cut pieces accessible. Remove and and discard both pieces of the long pipe. Unscrew the elbow-and-tee assembly from the radiator. Replace the short nipple with two short nipples connected by a union. Replace the long pipe with a longer pipe to account for the added length of the added nipple and union.

This will leave you with plumbing projecting from the right side a little more than your current hookup, but it's better than pulling everything apart down to the first union on that line which may be, as you say, two floors below.

When you unscrew the elbow-and-tee assembly from the radiator, the short nipple will probably remain fast to either the elbow-and-tee assembly or the radiator. It doesn't matter which, just leave it, and add the new nipple to the other side of the union.

You may need to separate the elbow from the tee in order to re-assemble the plumbing. If they are too rusted to come apart, consider that buying new ones is not really expensive and is a lot better than gouging your new floor.

Edit: I just realized that you may be able to make the assembly a little shorter by screwing a union directly onto a street elbow. The order of the new parts (left-to-right) will be: new long pipe, tee with cleanout plug, vertical short nipple, new street elbow, new union, horizontal short nipple, radiator.

Answer 2

"I'm not a plumber, nor a plumber's son..." but having watched them working with threaded pipe the trick seems to be finding the places where there is enough freedom for things to become longer (as the threads in both ends back out).

In this case ... lemme check the photo again ... it looks like that coupling piece between the radiator and the L connector might be the easiest thing to unscrew, though that might be riskiest for the radiator itself.

But it is entirely legitimate to cut somewhere and replace the cut piece later; pipe is cheap. Try to cut somewhere that leaves two pieces both large enough to be removed so the cut piece can easily be replaced... if you can't get it free, you can also replace the fitting the cut piece threads into (which suggests that you don't want to cut one immediately adjacent to the radiator).

If all else fails: Hire a plumber to disconnect the first radiator; watch him or her and use the same approach for the others. If you can't figure out how to reinstall, you can again essentially hire a plumber to teach you the technique.

And if that fails, just have the pro deal with the pipefitting. But I think you can do this.