Pipe Insulation FYI and Question

been

Phil,
What do you think about draperies touching steam radiators?

Patrick North

pipe insulation FYI and question

I've done some digging and have been told from the source that neither Icynene nor cellulose should be used in contact with steam pipes. In my case, I'm trying to insulate some outside walls that contain risers. My best guess right now is to cut into the wall at the riser to insulate with 'formed' fiberglass pipe insulation, then fill with one of these materials. No rep was willing to say _how_ much fiberglass would be needed to cover the pipe (to be safe)- probably for legal reasons- but both had similar max temps- around 180. Anyone with experience here? I'm guessing some 2" fiberglass would be adequate, but I'm not sure what I'll find behind the plaster- may not have much room.
Thanks,
Patrick

Brad White

What I get

Hi Patrick-

According to my program, with a 2" riser in a 75 degree ambient carrying 215 F. steam, I get the following surface temperatures:

1" thickness: 92 degrees F.


1.5" thickness: 86 degrees F.


2" thickness: 83 degrees F.

It would seem that any of these would yield a surface temperature not much above what a summer day would impose.

Yes, I would only use fiberglass with sealed ASJ.

My $0.02

Brad

Alan(OnVacationInOregon)Forbes

Fiberglass

We always use 1"-walled fiberglass, but this is California.

Tyler S

Hydro Air System insulation

I've just installed a hydro air system in the spec house that I'm building. I currently have one of these setups in my own home and the sub I hired to do it said he only used fiberglass insulation. I am unsure of his reasonings (efficiency, ease of installation, etc.) but I want to used the best overall insulation for the system in the house I am building. I am asking which insulation is proper for interior heat pipes and hot water lines?

Thanks in advance for any insight,
TS

Patrick North

Thanks

Thanks, all. I think I'll use the thickest wall fiberglass I can manage, and then fill that stud bay with fiberglass for good measure.
Thanks,
Patrick

Phil_17

Icynene against steam

Interesting. My Icynene installer had no hesitation whatsoever when I asked about covering steam pipes while insulating the underside of a crawl space in my house. I have had a short section (~4 ft) of horizontal runout enclosed in the stuff for about a year now with no issues whatsoever.

Looking at the product data sheet on their web site it does say that it should be at least 2" away from any heat emitting devices where the temperature exceeds 200 degrees.

Do I need to worry about burning down my house? I don't think so. Steam at atmospheric pressure is only 212, and even if you run 1-2 PSI the pipe is never going to exceed ~225 degrees... This value seems like an arbitrary cutoff (the 200 being such a nice round number).

Phil_17

I have draperies brushing over the tops of a couple of rad's. Been like this for two years with no issues (aside from the obvious impact on heat exchange and convection).

Nothing melted, nothing scorched... It takes a lot more than 212 degrees to harm any fabric that I've ever seen, and more like 400-500 to be an ignition concern for any common household material...

Who here hasn't put their hat or gloves on a radiator to dry?

Anyone ever started a fire that way?

All I get is comfy warm gloves :-)

-phil