Christian McArdle wrote:
Bearing in mind the cylinder/heater have been in place for 25 years
how difficult will the heater be to change.

There's no need to take the old one out. Just put an additional one
in near the bottom, which just requires a hole saw. This is a much
safer alternative to attempting to release a 25 year old one. Also,
check that the old one is indeed broken. It could be just a broken
thermostat, which is easily replaced.

If you do attempt to remove the old one, loosen it with the tank full.
Rather than putting on lots of torque to the spanner, make short
sharp blows on the end with a hammer. The shocks will be more
effective at loosening it, whilst reducing the tendency for the
cylinder to distort or crack. However, you should note that the
chances of failure are quite high and should have an alternative
solution in mind (i.e. cylinder replacement) and the ability to
rapidly drain the cylinder without causing damage to floors and
ceilings.

Christian.

FWIW I tried losening a stuck immersion element with a flat spanner
and it buckled the tank. the best tool for the job is a box type spanner
with a bar through it as you can control the rotation and deflection. the
flat type spanner seems to 'torque up' and in my case buckled the tank.

heat *is* beter than penetrating oil and if you slacken the outlet on top of
the tank (after cutting off the cold feed, obv) you only get whatever water
is held in the tube (half a litre) escaping rather than the gallons that escape
if you just crack the element and unscrew it (been there, done that)

I then cut the hot outlet 22mm at centrepoint and added a 22mm copper
pushfit joint to allow me to rotate the hot outlet pipe clear of the top of the
cylinder. I then syphoned out enough water to clear the element hole.

it's hot, I'm tired, but the OP should get the picture ;-)




RT