old pipes leave it or replace

[falcini]

hi everyone i am new to this forum my name is fabio and i am looking for some help
i am undergoing some home improvements and i am having a ceiling replaced when the ceiling was taken down i have had the chance to see the pipes that are running to the radiator and by surprise i noticed that these pipes are like silver colour at first i thought i was in trouble as i thought these pipes were made of iron then as i did not see any sign of rust i took a magnet to check if these pipes have iron but the magnet does not stick to them we have lived in this house for 25 years and never had a problem with this heating pipe system i dont know how far back these pipes were installed but this house was build in the 30's i found a dead pipe of the same material next to the fire place i cut it in half and it looks black in the inside but not sign of rust now the question is what kind of pipes are they? are they any good to guarantee many years to come or should i replace them with copper pipes calling a plumber sounds to me like i am going to be told that i have to replace them but i need a honest opinion as i am runnig out of money and i am puzzled whether i should really stretch my self and change all these pipes

 

[stevetheplumber]

this sounds like a pipe that was used during a copper shortage in the mid late seventies think it was called stabright if its not given any problems i see no reason to touch it however most of it nhas been removed long ago as it wasnt great tends to fail anywhere air gets in like open vents or cold feeeds

 

[falcini]

thank you i dont know what it is called but another couple of people mentioned some kind of name mixed with carbon apparently they are good pipes as they never rust but they could be a pain if you need to work on them every body says if they have worked so far dont touch them i hope you are right

 

[Bernie2]

Hmm!

Sounds like the stainless steel pipe we used in the seventies. Hard as rock and it could rust. But lets see now, I am not sure of its expected life, some say 100 years, I suppose it depends on its quality.