how do vertical radiator pipes get supported?

weil_fail

currently, my house has galvanized radiator pipes that run vertically from floor to floor outside of the walls. it appears that there is nothing supporting it, other than the floor-standing radiators. do you think there is a support of some kind inside floors? if one of those vertical runs gets replaced with copper, how does it need to be supported?

HVACNUT

It doesn't because you never use copper.

Jamie Hall

Are you quite sure that they are galvanized? Mostly they are "black iron". If this is steam, don't even think of replacing them in copper -- you will have expansion noises you won't believe. Replace like for like. If this is hot water, you could replace them with copper if you really needed to.

And why would you be replacing them?

But in answer to your question, there usually is no support, other than the radiator pipes or any other horizontal or near horizontal pipes at one end or the other, which may be on hangars.

STEAM DOCTOR

@weil_fail. The pipes probably probably are silver in color but are almost certainly not galvanized. The silver paint was added to black iron pipe(steel pipe in essence). Would not suggest replacing at all unless there is a compelling reason. The vertical steam pipes are rarely supported

EBEBRATT-Ed

Riser clamps otherwise know as friction clamps. Big box won't have them only a real supply house or on line

Jamie Hall

A very minor addition to @EBEBRATT-Ed 's comment, which is not always obvious: if you are going to use riser clamps, use one -- and only one -- on a given vertical length and make sure the pipe is unrestrained at the ends. Pipe expands and contracts with temperature, and trying to use more than one is going to create problems.

weil_fail

yeah, probably black iron. it's a hot water radiator.

why is copper not used?

JUGHNE

Your system could be nearly 80-100 years old.
Copper was not widely in use then because of expense.
Also copper expands more than iron and the pipes going upstairs would grow in length trying to lift the rad or bowing in the middle.....could be noise from expansion and contraction.

STEAM DOCTOR

Soldered joints can come apart. Expansion will stress the joints

weil_fail

what's the best material for hot water radiator pipes? still black pipe?

Jamie Hall

Copper is usable for hot water systems. They don't get anywhere near as hot as steam systems.

JUGHNE

There is plenty of copper used for BB heating that could run at high temp. But provisions are made for expansion. BB often drops to the basement and over and back up. That "U" shape allows for flexing of expansion.
Your vertical risers might make a problem because of the length.

weil_fail

gotcha.

do people typically use copper or hePEX near the boiler itself for all of the small connections to things like pumps and valves, then transition to black iron, or do they run black iron the whole way?

Jamie Hall

I would say that nowadays people use mostly copper near the boiler and either copper of hePEX out in the wilderness if they prefer the latter. The PEX is, in some ways, a little easier to work with -- but in my humble opinion copper makes a neater job, and doesn't sag between supports.

ChrisJ

Jamie Hall said:

I would say that nowadays people use mostly copper near the boiler and either copper of hePEX out in the wilderness if they prefer the latter. The PEX is, in some ways, a little easier to work with -- but in my humble opinion copper makes a neater job, and doesn't sag between supports.

There's a little bit of irony when people say they don't like pex because it sags etc and yet are perfectly content with NM-B or even MC instead of conduit in residential.

JUGHNE

Yes, I read a comment that with PEX plumbing it looks like the electrician installed it.

Jamie Hall

So long as the PEX is properly supported so that it doesn't sag when it's warm... no problem. Just for reference, I use mostly MC cable in the electrical work I do. Usually supported about every two to three feet -- sags are unacceptable. I use UF cable in wet or damp locations -- such as animal barns or outdoors, as neither NM-B nor MC is acceptable in those locations (even though the stuff is a pain to work with!). I do not use NM-B anywhere. Mice like it too much.

When I took over maintenance of the properties I care for, some PEX had been installed. In a few instances I will also use it -- such as negotiating weird vertical plumbing chases (there are times when a flexible pipe is the only alternative to major carpentry and plaster work!). Otherwise... no. It's coming out and being replaced by copper as I get around to it.