On Thu, 01 Jan 2004 18:36:24 +0000, kinsler wrote:


I need to fix a failed immersion heater in my hot water cylinder;
which seems in principle straightforward enough. The problem
is there seems to be no way of draining water out of the cylinder
without removing one of the elements! There are two heaters,
both side mounted one about a third of the way down, the other
at the bottom.

There is a "bolt" just below the top element, which might be where
a drain tap of similar should have been fitted, but I don't actually
know what it's for (if anything).

The hot water is drawn from the top of the cylinder, cold goes
in at the bottom; so shutting the inflow and opening the hot
taps has minimal effect on the amount of water in the cylinder.

It looks like I'll just have to take out the top element and try
to catch as much as possible in a bucket. Unfortunately, it's
at least several buckets worth, and it's going to gush out when
I remove the element -- and I'm not sure the flat downstairs needs
an in-house waterfall.

So this all sounds pretty impossible to do with any degree of
dryness. Any one got any suggestions or miracles that might
work better than a lot of towels and a hopeful waving of buckets?


Look around at the pipework on the inlet into the bottom of the HW cylinder
(HWC).
There may be
a) a drain point (attach hose expect the drain point to dribble a lot).
b) a valve at low level: possible to close it off, drain _roof_ tank (using cold
water) and then open the non HWC side pipework and use the valve to control
the emptying of the cylinder messy but possible.
c) with the inlet off you can drian to the top of the cylinder level.
you then open the pipework at the top of the cylinder (might not be
easy) and put a hose from the top into the cylinder to syphon off the HW.
When completely empty you can work on both immersions.
Also add a tee and a drain point or 1/4 turn service valve for future use.

HTH



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html