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Jun 10, 2009
46
7
8
North Cornwall
Hi, I've been asked to replace a leaking vented indirect copper cylinder. Water is acidic - borehole supply. Am I any better off with a stainless steel Cylinder and plastic pipework where possible or will customer just have to accept need to correct ph in their water supply. They have been reluctant so far. I'm getting mixed messages from merchants re stainless steel- As it too can corrode I'm told. Has anybody got experience dealing with this.
 
Hi, I've been asked to replace a leaking vented indirect copper cylinder. Water is acidic - borehole supply. Am I any better off with a stainless steel Cylinder and plastic pipework where possible or will customer just have to accept need to correct ph in their water supply. They have been reluctant so far. I'm getting mixed messages from merchants re stainless steel- As it too can corrode I'm told. Has anybody got experience dealing with this.
No experience of acidic water, but I would contact manufacturers, not merchants. Good luck.
 
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Hi, it is most unlikely that the issue is due to acidity in the water. Copper needs to be exposed to a fairly strong acid before it reacts.

In my my view it is more likely to be a result of electrolytic reaction between dissimilar metals in the system ( galvanised iron to copper?). This has probably been protected by an sacrificial anode inside the cylinder that has now come to the end of its life (dissolved).

The solution is to try to find the dissimilar metals in the system and remove / change them. Replace the cylinder - preferably for one with a Magnesium Alloy anode.

Fitting stainless steel (ss) cylinder ( provided that it is a decent grade of ss) will only move the corrosion point to where the dissimilar metals are in the system. Stainless steel will only react with very strong acids - I guess ones that would make you quite ill before the cylinder corroded through. The copper tank will have corroded where the anode was connected, once the anode had fully dissolved, the attack on the copper will have commenced

Hope this helps
 
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Hi, it is most unlikely that the issue is due to acidity in the water. Copper needs to be exposed to a fairly strong acid before it reacts.

In my my view it is more likely to be a result of electrolytic reaction between dissimilar metals in the system ( galvanised iron to copper?). This has probably been protected by an sacrificial anode inside the cylinder that has now come to the end of its life (dissolved).

The solution is to try to find the dissimilar metals in the system and remove / change them. Replace the cylinder - preferably for one with a Magnesium Alloy anode.

Fitting stainless steel (ss) cylinder ( provided that it is a decent grade of ss) will only move the corrosion point to where the dissimilar metals are in the system. Stainless steel will only react with very strong acids - I guess ones that would make you quite ill before the cylinder corroded through. The copper tank will have corroded where the anode was connected, once the anode had fully dissolved, the attack on the copper will have commenced

Hope this helps
Thanks both. The cylinder has only been in less than 5 years. I'm told pipework is all copper/plastic. We are not 100% sure leak is the cylinder - it might be on cold feed pipework which is out of view and inaccessible but in area of leak. Cylinder has to come out anyway so We thought about stainless. Manufacturers don't seem to like dealing with anything other than mains water supply - understandably so are unable to commit. I think we are going to opt for a grade 1 copper replacement with all connections and pipework visible and accessible. I found a company in Northern Ireland making copper cylinders specifically for well/borehole water but costs almost too high. Waiting for more bespoke prices before deciding.
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Thanks both. The cylinder has only been in less than 5 years. I'm told pipework is all copper/plastic. We are not 100% sure leak is the cylinder - it might be on cold feed pipework which is out of view and inaccessible but in area of leak. Cylinder has to come out anyway so We thought about stainless. Manufacturers don't seem to like dealing with anything other than mains water supply - understandably so are unable to commit. I think we are going to opt for a grade 1 copper replacement with all connections and pipework visible and accessible. I found a company in Northern Ireland making copper cylinders specifically for well/borehole water but costs almost too high. Waiting for more bespoke prices before deciding.
just to add visible pipework is pinholed so clearly a problem there
 
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