"Richard Skeen" wrote in message
...

The element has failed in one of the two immersion heaters on my hot
water cylinder. The problem is, I'm having real difficulty removing it
so I can fit a replacement.

I bought this spanner, but can't unscrew the immersion by hand:
http://www.screwfix.com/prods/29549/...ersion-Spanner

So far I've tried: standing on one end of the tommy bar, levering up the
other end against the floor with a car jack, and hitting it with a 4lb
club hammer, although admittedly not all at the same time. All I've
achieved is bending the cylinder at the immersion heater boss, even
though I kept it full of water for strength...

If you have bent the cylinder, you ought to give up now and buy a new one.
The distortion is a potentially weak point that could fail without warning.
No doubt someone will have a story of having had a distorted cylinder for
centuries, but the risk is still there. Aside from being the safest
solution, it will be easier than trying to get the heater out and you will
almost certainly end up with one that is better insulated.

Colin Bignell