National Art CI Rad cracked

MarkZeh

Radiator experts, need some advice. Sadly, just prior to installing an old National Art CI rad, pressure test failed only to reveal a crack in bottom side wall of #2 section of a 8 section 5 tube rad. Was going to be a little oversized but perfect to warm an unheated bathroom.

OK: my options?

Read some other Wall discussion on trying to repair an ARCO rad with JB Weld. Does not look promising. What are the thoughts of having it welded/sealed? Does not need to be pretty since the cracked part is not very visible.

Lastly, considering opening u the rad and removing the damaged section leaving the rad with 7 section which will still be more than enough heat output. Have never opened up a rad like this before. Considering she was assembled 100+ yrs ago, any tricks of the trade to disassemble? Some light torch heat and some tapping with hammer cushioning with wood block. Just my initial thoughts.

Any comments/suggestions welcome.

Also, starting to look for replacement but considering my house and this rad are from same era; circa 1908, would love to put her back in service.

Thanks for all.

best, Mark

Jamie Hall

First question. Steam or hot water? Makes a huge difference in how it might be repaired...

MarkZeh

Jamie, thanks. Hot Water

thanks again

Waher

JB Weld is not a good idea for anything other than an emergency stop-gap measure.

Depending on the extent of the damage either welding or brazing will be required. I wouldn't dismantle the radiator (yourself) unless absolutely necessary, that might cause more damage resulting in you having to discard more sections. If it needs to be dismantled and reassembled it's best to leave it to the shops that have the proper tools and experience to minimize the risk.

Jamie Hall

Then I'm sorry, but I can't think of a good way to fix the crack. JB Weld almost certainly won't hold against the pressure (it would, easily, on steam which is one twentieth the pressure), and welding cast iron is difficult, to put it mildly.

MarkZeh

Agree with everything you advised. Pressure test always at 15-20 psi. Normal HW boiler pressure, understand that steam is much lower. Most probably going to open her up and remove that section. re-assemble and P test again. Hopefully that's the ticket. Q: when reassembling, you apply some pre-dope to nipples as an extra measure?

thanks

mattmia2

Is it a push nipple radiator or a left-right threaded nipple radiator? Are there tie rods that hold it together?

MarkZeh

Mattmia2, tie rods so push nipples. See pics of Rad. The marked-up pic shows the unfortunate crack in the side wall. have not observed any other cracks. Plan is to disassemble, remove the damaged section, re-assemble and pressure test. If all goes well, the 7 sections will still provide a good amount of heat for the bathroom. Thanks

MarkZeh

Mattmia2, hello and HNY. Just to keep you in the loop on the resolution of this Rad. Appreciate all your help. Posted this to a different discussion about splitting Rads. Again, thank you for all your help.

best

Dear HeatingHelp folks. Can't thank all enough for their kind words of wisdom. Needed to install a CI Rad in a downstairs BR - no heat Brrrrr. Had an old, 1906?, CI rad National Art 5 tube 8 section 25" high would be perfect for BR. Got smart and pressure tested it prior to actual install and sadly she failed miserably. Thorough review showed that one of the sections had an ugly crack. Most likely it was left in the house with water in it and when water froze, she popped a section side wall. Pic attached. Followed advice from all the Rad Gurus on HH.com. Slit the rad with oak and metal wedges. She came apart just fine. Removed the single bad section. Push nipples were in good condition. Cleaned push nipple and section faces with fine wire wheel brush and steel wool. Used Rectorseal 5 to reassemble. Tightened entire Rad well with shortened rods. Re-pressure test and she held just fine. However, not just fine but bc my pressure tester gauge was damaged and not reading well I had to check with a regular tire pressure gauge. Rad was holding 55 psi for hours without fail. Deemed her 'Good to Go' at that point for very good reasons. Cleaned her, re-spray her like new and installed. Now only 7 sections but she gives off awesome heat and works like a charm. Again, thank you to every guy on HH.com that chimes in with their expert advise. Best web site anywhere. Other pics attached.