Stainless pipes potential for leaks going from gravity to combi

[mrbrunes]

Hi

My elderly mother's 60's house has a 27YO back boiler plus stainless pipes throughout (presumably s/s as they are quite shiny) but we are considering a combi (been through all the options and a combi makes most sense so far) and an installer has warned of the possibility of the pipework not withstanding the pressure. There are some copper sections with compression fittings to the backboiler presumably from when it was replaced in case that helps id the material.

What is the expected lifetime of s/s pipework?

The installer has said that if it does end up leaking when pressurised then a heat exchanger plus pump could be used for the heating, but of course this would be after going to the expense of flushing the pipework! Also another heat exchanger seems rather a hack. The floors are timber suspended but the disruption of replacing all the pipework would be rather too much for my mother to take!
Any suggestions or is it time to bite the bullet ...

 

[DP]

and an installer has warned of the possibility of the pipework not withstanding the pressure.

was he smoking grass before he uttered that nonsense
SS is MUCH stronger than copper, try cutting it with a hacksaw or pipe cutter
My concern would be the soldered fittings.

Clean the system and instal IG boiler as open vented.

 

[flameport]

Unlikely it's stainless steel.

Are the radiators of the same age as the pipes, and if so, what do they look like?

 

[oldbuffer]

1. It may not be stainless steel, but (more likely) "TruWell", "TruWeld", "Truwel" (spellings vary). This was a passivated steel pipe used during the copper shortage of the 70's. It is known to rust and would be well past its life span by now.
2. If it TruWell you would be advised to re-pipe the whole system.
3. Try putting a magnet on it. If it does not stick, it is most likely stainless steel. If it does stick is is more likely TruWell, but could be stainless.
4. TruWell can be cut with a hacksaw like mild steel. Stainless is much harder, and much more difficult to cut.

 

[polesapart]

"TruWell", "TruWeld", "Truwel" (spellings vary).

My preferred spelling is "Trubble".

 

[mrbrunes]

Tx for the info. I tried a magnet on a pipe under the stairs and it did not stick. (My first attempt stuck but I realised it was the mop handle - doh!)
The installer did mention passivated steel, so it may have been me that added the stainless part. I'll put the blunt down next time!

Any other ways of finding out the pipework health without hacking into a pipe???
I know some combis can be installed in open vented mode so could she have that for now to obtain much better efficiency savings and then have the pipework replaced as and when leaks occur?

 

[kidgreen61]

As said, it's not SS, it's Truwell, I recommend you get rid of the awful stuff

 

[ianmcd]

That is indeed Truwell, as already advised replace the lot, do not try to clean the system or it will leak like a sieve, Terrible stuff

 

[mrbrunes]

Unlikely it's stainless steel.

Are the radiators of the same age as the pipes, and if so, what do they look like?

Forgot to attach the rad pics, in case it makes any difference. Several are the older type, a couple have been replaced by the newer sort with the rounded top.

 

[DP]

I tried a magnet on a pipe under the stairs and it did not stick.

stainless steel. SS in not magnetic

About three months ago replaced a zbB with an IG combi. Lot of pipe work was SS and some copper

I coulcc do be wrong but if it was steel pipe as suggested, magnet would have stuck up it. If there is a deposit of magnetite within the pipe, magnet will Be attracted to it.

Run a file on the pipe. File will hardly mark the pipe if SS

 

[Nige F]

And if it's tru wel the coating will come off. FWIW I think it's stainless

 

[DP]

And if it's tru wel the coating will come off. FWIW I think it's stainless

Unless I am mistaken, tru wel had a copper coating with metal underneath. Where the fittings had weeped, the pipe would be rusted. Also was tru wel pipe bent with a pipe bender?

 

[Exedon]

Unless I am mistaken, tru wel had a copper coating with metal underneath. Where the fittings had weeped, the pipe would be rusted. Also was tru wel pipe bent with a pipe bender?

Certainly the coated steel I've seen in this area was copper coated.
Back in early 80s repiped 200 odd on one site that tube and screed floors not a good mix!

 

[mrbrunes]

I found some tiny text on one of the larger pipes BS 4127 which appears to make it stainless steel. And the magnet failure test help confirm that.
Phew!
Presume then it's safe to go combi if we decide that route?

 

[mrbrunes]

Hmm, an online boiler supplier that I just got some quick quotes from has told me that fitting a boiler to stainless steel (heating) pipework is against Gas Safe regs, and that it must all be replaced by copper. I'm struggling to understand this as I can't find any ref to mandating copper vs stainless pipework in the 1998 regs or Building regs Doc J.