Richard Skeen wrote on 04/04/2008 :
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.

Does anyone have any tips? The cylinder is probably about 12 years old
and this is a hard water area, so I imagine it's scaled up on the
inside. Any point in trying to soak penetrating oil into it overnight?
As it's a combination (fortic) type cylinder, it wouldn't be cheap to
replace.

Last resorts....

Angle grinder, to cut the top off then you might find it is free - if
not it should allow you to then get some Plusgas to soak down the
threads.

If that still doesn't help, cut around the copper to remove the boss +
element and buy a replacement boss to solder in.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk