On Wednesday, 13 March 2019 10:26:56 UTC, charles wrote:
In article , harry
wrote:
On Tuesday, 12 March 2019 18:52:04 UTC, wrote:
On Tuesday, 12 March 2019 07:41:21 UTC, harry wrote:
On Monday, 11 March 2019 17:37:33 UTC, misterroy wrote:
What could have caused the heating pipe to corrode so badly that it
failed? It was next to an external wall and lagged. The are a
couple of lengths of the pipe lying outside the building unused for
the same 6 years, other than the threaded ends, they look new.
image
https://drive.google.com/open?id=1o8...cqBdRGYatmQb6R

If it is attached to copper pipe elsewhere in the system, zinc and
copper are perfect for galvanic action. Depends too on the quality of
the water in the system. Inhibitors are available.

Is there some way to stop this corrosion in a CH system using copper
pipes & a galvanised steel cylinder/tank?


NT

The reason why galv water tanks rusted was the copper pipes they were
attached to. Now we have plastic tanks.

Generally, any inhibitor in the system won't be in the header tank, just
in the pipework. Obviously, a problem if it's a galv.steel tank.

You normally pour the inhibitor into the header tank from where it
circulates round the system.

You won't get much in the system if you do that.
The system has to be partially drained and then the inhibitor added to get in in the pipework/radiators.