I have caused a 5mm long hairline split in tne copper hot water tank whilst replacing the immersion. is it possible to repair it or will I have to replace?

Antony Dala, December 2007

I did repair a hole in a copper cylinder once, I used a VERY large soldering iron and puddled solder over the hole, it never leaked again.

For a split you would need a close fitting copper pach, clean the area very well and preferably 'tin' the cylinder and patch before trying to solder it on. Again, your going to need a VERY large soldering iron because the copper cylinder will rob the heat away from where your working.

Martin, December 2007

Advice I was given, and its worked for me many times, is to loosen the immersion BEFORE draining any water from the tank. When full the pressure of the water helps give some rigidity to the thin walled copper tank. Obviously dont loosen it to the extent water starts gushing out, but having broken the seal, it should unscrew easily once you've drained down the water. If you are lucky enough to have a top entry heater, then all you really need to do is shut off the fill supply, and empty no more than a sink full, before the water is lowered away from the heater entry point.

Alan R, December 2007

Its very unlikely that any tear would be fixable for any length of time - it could be soldered I guess but it wouldn't be reliable. I'd replace the tank if it was mine - at least then you could forget about it. Its dead easy to do what you have done though - its happened to me before. Twice!

John, December 2007