type M copper splitting on heating lines..

[LiQuId]

hot line off of hot water tank branches off to serve a heat exchanger in a basement in floor heating system. was called originally cause the owner suspected the gasket on the pump was leaking. changed the gasket, pressurized and have found pinholes in the copper piping, after talking to the owner I discovered that much of the copper had been failing and he had much replaced, So... plan is to change out the last 2 feet or so with better copper ( type L, originally piped in type M )

I'm pretty sure what is happening is that the heated water being softer is stealing elements from the copper piping, has anybody experienced anything similar? does this theory sound true?

basically I am wondering if I should suggest the installation of a sacrificial annode somewhere in the line as I would be stoked to leave my customer With no fear of future re-occurance of this problem. I am sure that type L will last longer regardless.

Note: it is the water side of the heat exchanger and not the glycol side being affected.

 

[johnjh2o]

If he has had pin holes in other locations a re-pipe may be in order. Depending on the water condition type M copper has been known to fail in 25-30 years. How old is the house?

John

 

[LiQuId]

The plan is to re-pipe what little copper is left with type L, house is only 10 years old but the water here is very rich in minerals and the pipng done is very shoddy work... boom time plumbing for sure. what has been re-piped was done mainly with pex but even at that done poorly with excessive couplings and redundant valves and what copper transitions are left are minimal with most of the pipes addapeted to pex.

this is exaclly why I never install type M copper myself... what would you wager the life on type L in the same conditions?

thanks for the response .

 

[johnjh2o]

That's hard to say how long L will last. Down here most of are homes are built on slabs and type L copper has been used under the slabs for some time. I have seen type L fail in less then 15 years. With the same pin hole leaks you are experiencing. But I think it has more to do with our soil conditions then are water conditions. Although there are some areas with some real aggressive water. We recommend a re-pipe after the second slab leak.

John

 

[SlowDrip]

It is also possible that the previous plumber used defective or even used piping. Copper pipe recalls are rare but not unheard of, and some shadier plumbers will have no issue re-using pipe from a previous job, especially in a boom time.

 

[LiQuId]

inspection of the pipe that came out shows that the joints were roughly cut ( im thinking sawzall ) and not reamed at all. pipe interior looks wire drawn and there is massive mineral deposits around the non reamed edges.
the last plumber that came in switched most of the piping to pex but did so in a sloppy kind of way.

type L in now and recomendation for a re-piping of the system in the future to eliminate all the redundant valves and sloppy runs.

I have re used copper piping myself..... as sleeving to redi rod insert hangars...


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