Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't really
travel) that the bottom (main) heater has failed and needs replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank -
is there anything else I should look out for when doing the replacement?
I have an immersion heater spanner already.

It's an Albion (now part of Kingspan?) cylinder, 170l Stainless
unvented, SU170D. I can't track down the heater part number which is
14P395 "STAINLES" (sic) but it seems to be a normal 3kW part. I assume
the thread is 1 3/4 but I don't know what the length should be 11" or 14".

TIA for any help.

On 26/04/2020 10:56, Grumps wrote:
Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't really
travel) that the bottom (main) heater has failed and needs replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank -
is there anything else I should look out for when doing the replacement?
I have an immersion heater spanner already.

It's an Albion (now part of Kingspan?) cylinder, 170l Stainless
unvented, SU170D. I can't track down the heater part number which is
14P395 "STAINLES" (sic) but it seems to be a normal 3kW part. I assume
the thread is 1 3/4 but I don't know what the length should be 11" or 14".

TIA for any help.

It might prove a little difficult to undo and unscrew the faulty
immersion element. How old is it? Any sign of additional sealant or
corrosion? They can be very stiff to undo.

If you try loosening it - try first to see if it will move with a full
tank of water so it has some weight to counterbalance the spanner force.
The danger of that is that it might leak afterwards!

Last one I did came undone but distorted the tank slightly.

Unless she cant do without the immersion heater it might be best left
until this virus bollyarks is over and done with -- just in case it wont
undo and (worst possible case) need a replacement tank ?????

--
Ask how to email me.

On 26/04/2020 11:15, Kellerman wrote:

It might prove a little difficult to undo and unscrew the faulty
immersion element. How old is it? Any sign of additional sealant or
corrosion? They can be very stiff to undo.

If you try loosening it - try first to see if it will move with a full
tank of water so it has some weight to counterbalance the spanner force.
The danger of that is that it might leak afterwards!

Last one I did came undone but distorted the tank slightly.

Unless she cant do without the immersion heater it might be best left
until this virus bollyarks is over and done with -- just in case it wont
undo and (worst possible case) need a replacement tank ?????



I had to resort to the method shown in this video

https://www.youtube.com/watch?v=wpz7PbcSjdI

As there is a small amount of plastic in the fitting - temporarily
disable any nearby smoke alarm.

The quality of the spanner can also make a big difference. Those made
from a stamped out flat piece of steel can easily distort before the
fitting moves.

https://youtu.be/mZ2MT0SKVZY?t=236

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 26/04/2020 11:15, Kellerman wrote:
On 26/04/2020 10:56, Grumps wrote:
Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't
really travel) that the bottom (main) heater has failed and needs
replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank
- is there anything else I should look out for when doing the
replacement?
I have an immersion heater spanner already.

It's an Albion (now part of Kingspan?) cylinder, 170l Stainless
unvented, SU170D. I can't track down the heater part number which is
14P395 "STAINLES" (sic) but it seems to be a normal 3kW part. I assume
the thread is 1 3/4 but I don't know what the length should be 11" or
14".

TIA for any help.

It might prove a little difficult to undo and unscrew the faulty
immersion element. How old is it? Any sign of additional sealant or
corrosion? They can be very stiff to undo.


I replacd an immersion heater once, later for another reason the tank
failed and I removed it. For fun I then tried to remove the immersion
heater which was impossible without damaging the tank. Hard area. The
local scrap merchant gave me some money for the old tank after weighing
it. I always wondered how much of the weight was due to the hard water.

If I were the OP I would first make sure that I could buy a replacement
tank quickly and that I could then fit it as many of the connections
might be in a different position.

--
Michael Chare

On Sun, 26 Apr 2020 11:53:52 +0100, alan_m
wrote:

On 26/04/2020 11:15, Kellerman wrote:

It might prove a little difficult to undo and unscrew the faulty
immersion element. How old is it? Any sign of additional sealant or
corrosion? They can be very stiff to undo.

If you try loosening it - try first to see if it will move with a full
tank of water so it has some weight to counterbalance the spanner force.
The danger of that is that it might leak afterwards!

Last one I did came undone but distorted the tank slightly.

Unless she cant do without the immersion heater it might be best left
until this virus bollyarks is over and done with -- just in case it wont
undo and (worst possible case) need a replacement tank ?????



I had to resort to the method shown in this video

https://www.youtube.com/watch?v=wpz7PbcSjdI


It is an internally insulated stainless steel high pressure tank, not
a copper hot water cylinder. A blowlamp is the last thing to use on
it

On Sun, 26 Apr 2020 11:15:52 +0100, Kellerman
wrote:


It might prove a little difficult to undo and unscrew the faulty
immersion element. How old is it? Any sign of additional sealant or
corrosion? They can be very stiff to undo.

If you try loosening it - try first to see if it will move with a full
tank of water so it has some weight to counterbalance the spanner force.
The danger of that is that it might leak afterwards!

It is an insulated stainless steel pressure vessel and the lower
thermostat is near the bottom of the tank so any attempt at removing
it when the tank is full or partially full will most certainly produce
an impressive leak.

Last one I did came undone but distorted the tank slightly.

If you manage to distort a high pressure tank at all it would need to
be replaced.

On Sun, 26 Apr 2020 10:56:10 +0100, Grumps wrote:

Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't really
travel) that the bottom (main) heater has failed and needs replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank -
is there anything else I should look out for when doing the replacement?
I have an immersion heater spanner already.

Immersion heaters for pressurised vessels must have a built in
overheat thermostat. The seal around the heater is usually made in the
factory so you don't often have the problems of plumbers in the past
slathering everything in sealant so removal isn't too difficult.
Refitting must be done carefully making sure the gasket surfaces are
absolutely clean. Make sure you know the refill procedure for the
tank and expansion vessel before you start.

On 26/04/2020 13:37, Peter Parry wrote:
On Sun, 26 Apr 2020 10:56:10 +0100, Grumps wrote:

Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't really
travel) that the bottom (main) heater has failed and needs replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank -
is there anything else I should look out for when doing the replacement?
I have an immersion heater spanner already.

Immersion heaters for pressurised vessels must have a built in
overheat thermostat. The seal around the heater is usually made in the
factory so you don't often have the problems of plumbers in the past
slathering everything in sealant so removal isn't too difficult.
Refitting must be done carefully making sure the gasket surfaces are
absolutely clean. Make sure you know the refill procedure for the
tank and expansion vessel before you start.

This cylinder did have a new expansion vessel fitted about a year ago
(maybe more) and I watched the plumber do it (unless you know all the
gotchas, I'm not sure I'd want to mess around with a mains fed hot water
tank). The cylinder is about 15 years old.
But what I don't recall is what the refill procedure was. Where would I
find that? Is the procedure not the same across a lot of unvented cylinders?

On 26/04/2020 10:56, Grumps wrote:
Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't really
travel) that the bottom (main) heater has failed and needs replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank -
is there anything else I should look out for when doing the replacement?
I have an immersion heater spanner already.

It's an Albion (now part of Kingspan?) cylinder, 170l Stainless
unvented, SU170D. I can't track down the heater part number which is
14P395 "STAINLES" (sic) but it seems to be a normal 3kW part. I assume
the thread is 1 3/4 but I don't know what the length should be 11" or 14".

TIA for any help.

Our Immersion heater has as an over heat cutout which once cut out. It
is a little button under the cap that needs to be pushed down to be
reset. It only did it once, I replaced the thermostat (which is
removeable on ours, it slides into a 'tube' under the cap), on the
assumption it was probably the reason.



--
https://www.antislavery.org/slavery-...forced-labour/

On 26/04/2020 14:08, Brian Reay wrote:
On 26/04/2020 10:56, Grumps wrote:
Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't
really travel) that the bottom (main) heater has failed and needs
replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank
- is there anything else I should look out for when doing the
replacement?
I have an immersion heater spanner already.

It's an Albion (now part of Kingspan?) cylinder, 170l Stainless
unvented, SU170D. I can't track down the heater part number which is
14P395 "STAINLES" (sic) but it seems to be a normal 3kW part. I assume
the thread is 1 3/4 but I don't know what the length should be 11" or
14".

TIA for any help.

Our Immersion heater has as an over heat cutout which once cut out. It
is a little button under the cap that needs to be pushed down to be
reset. It only did it once, I replaced the thermostat (which is
removeable on ours, it slides into a 'tube' under the cap), on the
assumption it was probably the reason.

You're right. It could be the thermostat.
A few easy tests I can make once this covidy-bolloxy thing settles down.

On Sunday, 26 April 2020 11:15:47 UTC+1, Kellerman wrote:
On 26/04/2020 10:56, Grumps wrote:
Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't really
travel) that the bottom (main) heater has failed and needs replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank -
is there anything else I should look out for when doing the replacement?
I have an immersion heater spanner already.

It's an Albion (now part of Kingspan?) cylinder, 170l Stainless
unvented, SU170D. I can't track down the heater part number which is
14P395 "STAINLES" (sic) but it seems to be a normal 3kW part. I assume
the thread is 1 3/4 but I don't know what the length should be 11" or 14".

TIA for any help.

It might prove a little difficult to undo and unscrew the faulty
immersion element. How old is it? Any sign of additional sealant or
corrosion? They can be very stiff to undo.

If you try loosening it - try first to see if it will move with a full
tank of water so it has some weight to counterbalance the spanner force.
The danger of that is that it might leak afterwards!

Last one I did came undone but distorted the tank slightly.

Unless she cant do without the immersion heater it might be best left
until this virus bollyarks is over and done with -- just in case it wont
undo and (worst possible case) need a replacement tank ?????

--
Ask how to email me.

To easily undo a traditional immersion heater. You need a hacksaw blade with one end wrapped in tape to form a handle.
Use it to saw out the fibre ring, ie work all round the joint circumferentially until its cut right through (you can easily feel this)

Do NOT try to force things if the heater is tight (it probably will be) Use the saw trick
You will heave to clean up the flange afterwards so take a file and emery paper. Put some Plumbers Mait on the new fibre joint.

On Sunday, 26 April 2020 10:56:13 UTC+1, Grumps wrote:
Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't really
travel) that the bottom (main) heater has failed and needs replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the tank -
is there anything else I should look out for when doing the replacement?
I have an immersion heater spanner already.

It's an Albion (now part of Kingspan?) cylinder, 170l Stainless
unvented, SU170D. I can't track down the heater part number which is
14P395 "STAINLES" (sic) but it seems to be a normal 3kW part. I assume
the thread is 1 3/4 but I don't know what the length should be 11" or 14".

TIA for any help.

Some stainless steel cylinders have non-traditional immersion heaters that your tradional spanner won't fit.
You have to buy a heater for that particular cylinder.
~Expensive too.

Peter Parry has brought this to us :
Immersion heaters for pressurised vessels must have a built in
overheat thermostat.

All immersion heaters have to have the overheat stat now..

Brian Reay explained on 26/04/2020 :
Our Immersion heater has as an over heat cutout which once cut out.

That might have been the over-heat trip manufactured a bit low, with
the main stat set a bit too high.

If only people would realise that it is the gasket that created the seal -
the tread it sher to pull the faces together - and what about a smear of
coppaslip?

On 27/04/2020 18:56, John wrote:
If only people would realise that it is the gasket that created the seal -
the tread it sher to pull the faces together - and what about a smear of
coppaslip?

Indeed. I'm not a plumbing expert, but that's how I understand the
situation.
The immersion manufacturers that I've read installation instructions for
say you should only need to use the supplied gasket; no thread sealer is
needed. One did suggest using PTFE as a lubricant.

Grumps wrote in :

On 27/04/2020 18:56, John wrote:
If only people would realise that it is the gasket that created the
seal - the tread it sher to pull the faces together - and what about
a smear of coppaslip?

Indeed. I'm not a plumbing expert, but that's how I understand the
situation.
The immersion manufacturers that I've read installation instructions
for say you should only need to use the supplied gasket; no thread
sealer is needed. One did suggest using PTFE as a lubricant.




So many plumbers and others seem to want to use sealants and gunks on all
threads - perhaps it adds to the mystique of the trade and gives them more
work in the future when things won't come apart. Same wit compression
fittings. The thread is there to apply a clamping force. Cleanliness is the
most important thing.

On 26/04/2020 12:53, Peter Parry wrote:
On Sun, 26 Apr 2020 11:53:52 +0100, alan_m
wrote:

On 26/04/2020 11:15, Kellerman wrote:

It might prove a little difficult to undo and unscrew the faulty
immersion element. How old is it? Any sign of additional sealant or
corrosion? They can be very stiff to undo.

If you try loosening it - try first to see if it will move with a full
tank of water so it has some weight to counterbalance the spanner force.
The danger of that is that it might leak afterwards!

Last one I did came undone but distorted the tank slightly.

Unless she cant do without the immersion heater it might be best left
until this virus bollyarks is over and done with -- just in case it wont
undo and (worst possible case) need a replacement tank ?????



I had to resort to the method shown in this video

https://www.youtube.com/watch?v=wpz7PbcSjdI


It is an internally insulated stainless steel high pressure tank, not
a copper hot water cylinder. A blowlamp is the last thing to use on
it

A quick Google suggests that this type of element is available at about
£50. It should undo OK (I misread the OP) provided only the original
gasket has been used. Check first, as mentioned, that the element is
faulty - definitely open circuit, that the over temperature trip has not
gone off and that the thermostat is OK.


--
Ask how to email me.

On 27/04/2020 18:56, John wrote:
If only people would realise that it is the gasket that created the seal -
the tread it sher to pull the faces together - and what about a smear of
coppaslip?

While this is true, that doesn't stop limescale deposits forming in the
clearance gaps between the non contact thread faces. My preferred
fitting method on a heater that needs replacing every year or so (long
story) used to be to put a thick layer of PTFE tape on the threads only.
Excess extrudes and keeps the clearances filled, very much reducing the
amount of deposits. More recently I have been using the soft sealants
that claim to be "liquid PTFE" (although they are obviously not), for
the same reason.

On 26/04/2020 14:36, Grumps wrote:
On 26/04/2020 14:08, Brian Reay wrote:
On 26/04/2020 10:56, Grumps wrote:
Hi All
Daughter has an unvented hot water cylinder in her flat which has two
3kW heaters. We believe (although I haven't checked as shouldn't
really travel) that the bottom (main) heater has failed and needs
replacing.
Apart from getting the correct length and thread diameter of the new
heater, switching off the electric to the timer, and draining the
tank - is there anything else I should look out for when doing the
replacement?
I have an immersion heater spanner already.

It's an Albion (now part of Kingspan?) cylinder, 170l Stainless
unvented, SU170D. I can't track down the heater part number which is
14P395 "STAINLES" (sic) but it seems to be a normal 3kW part. I
assume the thread is 1 3/4 but I don't know what the length should be
11" or 14".

TIA for any help.

Our Immersion heater has as an over heat cutout which once cut out. It
is a little button under the cap that needs to be pushed down to be
reset. It only did it once, I replaced the thermostat (which is
removeable on ours, it slides into a 'tube' under the cap), on the
assumption it was probably the reason.

You're right. It could be the thermostat.
A few easy tests I can make once this covidy-bolloxy thing settles down.

So I managed to visit and tested the thermostat and heating element. The
over heat cutout had tripped and all it needed was to be reset. If it
has tripped once, will it likely trip again?
Anyway, bought a replacement to be safe, and will install in a few days.