What causes radiators to crack?

Dairon421

I went to a house today and 3 radiators was cracked. What causes this? 

pecmsg

Freezing?

Dairon421

pecmsg said:

Freezing?

Have no clue, but they are cast iron radiators.

JohnNY

Yes. If 3 radiators were cracked in one home it's because they froze.

Jamie Hall

If they are genuinely cracked and not leaking between sections, the only thing that can crack them is freezing. Well, not the only thing -- a very hard blow such as with a sledge hammer or a really hot localized fire. I think you might know about those.

If this is or was a hot water system and it wasn't either drained or freeze protected, and the building went below freezing -- even for a relatively short time -- that's what did it.

pecmsg

If i hit them with my Ford they'll probably survive..................The Ford i wouldn't put money on!

Steamhead

@Dairon421 , if that many radiators are cracked, there's a pretty good chance the pipes and maybe the boiler are too. If you buy that house, figure on a completely new system.

Me? I'd look elsewhere.

pecmsg

Are you looking at purchasing this property?

Dairon421

pecmsg said:

Are you looking at purchasing this property?

No sir, just was doing a boiler cleaning and found crack radiators

pecmsg

How was there water in the system with broken rads?

New England SteamWorks

If one radiator was cracked, it could be anything. But with three it has to be freezing.

Paulvar1

My house is a steam system with nice cast iron radiators,  2 have cracked over the last 35 years that I lived here. 

acavan

Don't get freezing weather here but when we had our nine ~100 year old cast iron steam radiators refurbished, two had cracked sections. (A total of three cracked sections out of 91 sections in all.)

136lin

Where were the cracks? I've  never seen a one pipe steam system crack from freezing (that doesn't mean they don't) but they could crack from other causes.
If this was a hot water system freeze cracking is almost inevitable if the system wasn't drained.

jimshaw

I know this sounds odd and maybe impossible, however about 1 year ago we got a call from homeowner that had three cracked cast iron baseboards. One radiator actually had a chunk blown out of one section.
This is a hot water system. He admitted he had another contractor install a new boiler because the old cast iron boiler had failed. (no elaboration on 'failed)
The other contractor installed a boiler but not much else. After the replacement the 30 lb relief valve started going off, so they replaced it and so on and so forth for an unadmitted amount of time. The relief valve was replaced again and again and finally they got a "good one"! Then the radiators cracked and we were called. The original contractor had ended up putting in a 150LB relief valve and never ever did check the expansion tank, which was of course the real problem all along. We installed a properly sized expansion tank and a new 30 Lb. relief valve and no more problems. This system definitely never froze.

ratio

Scary.

Jamie Hall

Well, yeah, that would also do it. @jimshaw . And in a situation like that, it's a wonder that someone didn't get killed...