Immersion heater element length

When the element is fitted from above it usually is the 27 inch version.

The 11 inch versions are fitted in the side and used on economy 7 setups.

Adam

Looking at the angle of insertion - as suggested by John - it does look as
if the 27 inch one would fit ok. The only problem would seem to be is
whether or not it would come into contact with the heat exchanger.

It will not come into contact with the heat exchanger.

OK so I have only swapped two immersions this year (it is a job I try to
avoid).

The threads align the immersion so that it does not touch the exchanger.

Adam

Thanks for that. I'll get the 27 inch one. In the [unlikely] event that it's
wrong, I suppose I can always take it back - be a nuisance, though!

Then the simplest answer would be to get one of each on the basis that you
can take back the one you don't use at your leisure.

Steve

That makes perfect sense, of course, except for the fact that I don't mind
taking things back to be exchanged but I don't like saying to them - "I
haven't used this one, can I have my money back please?"!

Two tips.  Start spraying the thread with WD40 or similar a few days before
you try to remove it.  Buy the heaters at Wickes who have a no quibble
returns policy.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

Excellent tips, thank you. I was going to Screwfix, which is about 30 miles
away (we live out in the sticks!), and there is a Wickes nearby so I think
I'll do what you recommend.

I was always advised not to drain the cylinder until after 'breaking the
seal' of the heater. The logic being that copper cylinders are a bit like
baloons - they need the internal pressure to give them strength. Is this
still accepted as the best way?

Thanks
OJ

There is no need to drain the cylinder at all for this. Quite often there is
no means by which to drain the cylinder.

Drain or isolate the header tank and just catch any water that runs out from
the immerion hole with some towels.

Adam

You may even be lucky and find an isolating valve twixt header tank and
cylinder.   Mine has that and it makes life very easy.
--
Tinkerer

It takes no luck to find an isolating valve between the header tank and the
cylinder.

It takes good luck to find an isolation valve between the header tank and
the cylinder that actually works:-)

Adam

adamwadsworth@blueyonder.co.uk (ARWadsworth) wrote:


I had to change my bottom immersion (short) about a year ago. It had only
been fitted a few years ago. No matter what I did or used, I just couldn't
shift it. In the end I had to replace the whole tank. The long immersion
in the top (fitted at the same time as they were cheap, but never used)
was jammed solid as well. Really pxxxd me off as what was going to be a
half hour's job took over three days as the plumbing had to be altered to
fit the connections on the new tank.

Roger

27" is what you require for your indirect cylinder.

sometimes the length is printed on the label on the head part

All that's printed is 'NL27PT' - which does seem to suggest 27inch. I'm off
to get one now, I will report back.

It's a Newlec one. The Newey and Eyre website confirms that it is 27inch.
The 11inch ones are listed as 'NL11'.


Many thanks to everyone for the superb help and tips.

Now you've got the hard bit.   Unless you're lucky.....
--
Tinkerer

Well I got the new element - it was the 27inch one -  it is now fitted and
working ok. But you are correct, and I was a bit lucky! I can see that there
are many possible pitfalls and that some luck is needed. First of all (spot
on, Adam) there was an isolation valve between the header tank and the
cylinder - but the damn thing didn't work (not until some banging, WD40 and
lots of heat were applied anyway!).

Then came the actual job of getting the old one out - and it was a very old
one! - the cylinder was replaced in 1996, but I think that the immersion
element was much earlier and had been re-used. First of all the proper box
spanner that I got wasn't a very good fit - it was too big, I think that the
element flange hexagon was an imperial size. I had sprayed WD40 on it some
hours earlier - as recommended here, but I didn't have time to give days as
advised. Even after wedging the box spanner to get a decent fit, and tapping
it with a hammer, it still wouldn't budge.

Thankfully, after using the heat gun on it for a fair time (choking myself
on fumes from the cylinder lagging and setting off the smoke alarms in the
process!) I got it to move - hurrah! As I took it out I was surprised to
find the cylinder full to the brim - even though I had the isolation valve
closed and the hot taps open (with no water coming out of them). By placing
a couple of towels around the immersion heater hole and gently pulling it
out, I was able to clean up around the fitting and put the new element in
place without there being much water splashing about.

Yep, I think it could be a real sod of a job if things went badly wrong on
you. As it was I had real visions of having to replace the entire cylinder -
at around 200, not to mention loads of work and hassle - not a pleasant
prospect. Very grateful that it's done - and many, many thanks once again to
everyone for their help.

If I could pass on one or two tips on the basis of this experience, I would
say that:

1. Make sure that the isolation valve (if there is one) supplying the
cylinder is functioning ok before you start.

2. Tie up the ball valve of the expansion tank in the loft as a precaution -
better than turning off the cold water supply to the whole house (could be
while before it can be turned back on again!).

3. If your plumbing is quite old (like mine!), and things like stop taps and
isolation valves haven't been disturbed for a while, it might be worth
having a pipe freezer kit on stand-by.

4. Make sure that you have plenty WD40 and a heat gun available.

5. If the old element is quite stubborn to shift, and you need to give it a
few bangs with a hammer, make sure that the cylinder is full of water to
lessen the chances of damaging it.

6. Best of luck - you might need it!