Insulation for steam pipes

Alden Maddry

What is the best type of insulation for insulating my steam supply pipes? (Some of the pipes are copper (right out of the boiler) but most are 2" diameter black pipe.)

EdTheHeaterMan

Fiberglass

Alden Maddry

rather than foam insulation?

EdTheHeaterMan

Many foam insulations will melt or get brittle on the heat associated with steam.
https://www.grainger.com/product/4LFD3?gclid=Cj0KCQjwit_8BRCoARIsAIx3Rj6pgzipRnshp5FtL8bYvtdw-88d5D4aSRhxmOl0t1RsM8nn8rNjWHUaAqrVEALw_wcB&cm_mmc=PPC:+Google+PLA&ef_id=Cj0KCQjwit_8BRCoARIsAIx3Rj6pgzipRnshp5FtL8bYvtdw-88d5D4aSRhxmOl0t1RsM8nn8rNjWHUaAqrVEALw_wcB:G:s&s_kwcid=AL!2966!3!281698275774!!!g!471564520201!&gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231

pecmsg

Alden Maddry said:

rather than foam insulation?

YES

Jamie Hall

Alden Maddry said:

rather than foam insulation?

Fiberglass. The various foam insulations, while admittedly inexpensive and easy to install, are not rated for steam temperatures and, as @EdTheHeaterMan says, will get brittle and crack and crumble remarkably fast.

That said... I'm concerned about your comment about copper pipes right out of the boiler. Steam mains, particularly the near boiler piping, should never be done in copper. Sometimes one gets lucky and the expansion of the copper won't hurt -- much. Other times, depending on exactly how the pipes are run and their sizes, the expansion will quite cheerfully demolish the boiler in a matter of a few years. How does it happen that copper was used instead of the black iron which is required?

Alden Maddry

I'm not sure why the steam mains were done in copper... they were in place when I bought the house 8 years ago... and so far I haven't had any problems with these pipes... Are these pipes enough of a problem that I should have them redone?

pecmsg

Alden Maddry said:

I'm not sure why the steam mains were done in copper... they were in place when I bought the house 8 years ago... and so far I haven't had any problems with these pipes... Are these pipes enough of a problem that I should have them redone?

Maybe........Maybe Not!

Can you post some pictures of the boiler and near piping?

Alden Maddry

Here are a couple of pics of the copper steam mains coming out of the boiler - in the first picture you can see where the copper transitions to black pipe... in terms of insulating the pipes would insulating the copper pipes create any problems? (more than insulating black pipe).

Alden Maddry

second picture shows the transition not the first picture.

pecmsg

Wrong material for that boiler! Has it been there years yes, is it right NO!

Personally don't waste money insulating it, have it replaced and insulated at the same time!

mferrer

Yikes, I agree with Jamie Hall and the concern about copper tubing on steam lines.
Copper expands and contracts a lot more than steel and cast iron. Although the difference here may not pose a threat to causing the cast iron heat exchanger to leak, it may produce a nasty copper steam leak in the future.
The continuous expansion and contraction from the high heat of the boiler can work on those soldered joints over time causing them to fail.
Just because it has been ok for years doesn't mean it doesn't pose a thread down the road. Steel pipe and cast iron fittings last for decades or more. Rads and piping in buildings have lasted more than a century because they're far away from the intensity of heat from the boiler and the corrosiveness of the condensate. Piping near a steam boiler doesn't last as long. Better to have the Industry Standard's suggested material: steel pipe and cast iron fittings.
Many folks use copper because it's easier to install. A pipe threading machine is large, noisy, messy and heavy. So is all the material. But it's the right way to go. In the end, it's safe, efficient and cost effective.

nicholas bonham-carter

No only is the material choice wrong, but I suspect so is the size of the riser, and header, which you can check on the online boiler manual.
It may also call for 2 risers.--NBC

Dave0176

Peerless was conservative with their piping sizes on the 61