I've just found that our hot water cylinder is weeping from the joint
between the body and the top. Since it's over 40 years old (I
assume), it's probably simpler to replace than repair. Now, I'm sure
there are rules about who can and can't do this, so let's assume that
I'm buying one and getting a plumber to fit it, in the same way as I
would never do anything electrical or with gas fittings (!).

The house has hot air heating (sadly), which means it's immersion
heater only for the DHW. I have no intention of changing this as the
house is going onto the market soon and I don't want to start any new
major jobs.

Anyway, I've never played with hot tanks before but this is clearly a
direct cylinder. Screwfix do what seems to be the best buy (
http://www.screwfix.com/prods/49608/...YJMCSTHZOCFFI#
) but the description says it has a 'large heating coil', which sounds
wrong for a direct cylinder to me: Is this a typo or am I missing
something?

The real question: Does anyone know if the location of connections
(cold in, hot out, immersion heater) is standard? If there's any
choice, I'll investigate the market to see what's the easiest fit.

Similarly, is there anything to consider in terms of immersion heater
elements? I seem to recall reading that modern cylinders can have two
heater bosses and, presumably, this means they can be heated faster.
All the elements I can see (eg TLC) are 3kW: Seems to me that 2 x 3kW
is too much for the existing 20A supply. Does that mean I have to run
another 20A feed or is it reasonable to just cap one boss off? (We've
got by for years with one element and I'd rather not have to feed it
with a new circuit if I can avoid it.)

On 16/05/10 22:51, GMM wrote:
The real question: Does anyone know if the location of connections
(cold in, hot out, immersion heater) is standard? If there's any
choice, I'll investigate the market to see what's the easiest fit.

No standards that's I've ever noticed - it all seems pretty random. If
you shop around, you might find something close that will require the
lest fiddling with the pipework.


Similarly, is there anything to consider in terms of immersion heater
elements?

Element length for one.


I seem to recall reading that modern cylinders can have two
heater bosses and, presumably, this means they can be heated faster.

And so that the top one can be used to "top up" the tank. If this is top
mounting, vertically alighned, you may expect to want a shorter element.
If the other boss is also top mounted, you'd want a long element to
reach down the tank. If the bosses are side mounted, one nearer the top
and one nearer the bottom then you'll be needed shorter elements so as
not to foul the other side of the cylinder.

All the elements I can see (eg TLC) are 3kW: Seems to me that 2 x 3kW
is too much for the existing 20A supply. Does that mean I have to run
another 20A feed or is it reasonable to just cap one boss off? (We've
got by for years with one element and I'd rather not have to feed it
with a new circuit if I can avoid it.)

As heater are cheap, fit two and wire the bottom one only. At least the
next inhabitant can wire teh top one if they want faster recover or top
up mode. If you're feeling less well inclined to spend money (who isn't
right now) cap it off.

Yes, 2 heaters is too much by far for a 20A circuit.

HTH

Tim

--
Tim Watts

Hung parliament? Rather have a hanged parliament.

On 16 May, 23:28, Tim Watts wrote:
On 16/05/10 22:51, GMM wrote:

The real question: *Does anyone know if the location of connections
(cold in, hot out, immersion heater) is standard? *If there's any
choice, I'll investigate the market to see what's the easiest fit.

No standards that's I've ever noticed - it all seems pretty random. If
you shop around, you might find something close that will require the
lest fiddling with the pipework.

Similarly, is there anything to consider in terms of immersion heater
elements?

Element length for one.

I seem to recall reading that modern cylinders can have two

heater bosses and, presumably, this means they can be heated faster.

And so that the top one can be used to "top up" the tank. If this is top
mounting, vertically alighned, you may expect to want a shorter element.
If the other boss is also top mounted, you'd want a long element to
reach down the tank. If the bosses are side mounted, one nearer the top
and one nearer the bottom then you'll be needed shorter elements so as
not to foul the other side of the cylinder.

All the elements I can see (eg TLC) are 3kW: *Seems to me that 2 x 3kW
is too much for the existing 20A supply. *Does that mean I have to run
another 20A feed or is it reasonable to just cap one boss off? *(We've
got by for years with one element and I'd rather not have to feed it
with a new circuit if I can avoid it.)

As heater are cheap, fit two and wire the bottom one only. At least the
next inhabitant can wire teh top one if they want faster recover or top
up mode. If you're feeling less well inclined to spend money (who isn't
right now) cap it off.

Yes, 2 heaters is too much by far for a 20A circuit.

HTH

Tim

--
Tim Watts

Hung parliament? Rather have a hanged parliament.

Thanks Tim: Probably easier to get a second element than find a plug
for a dirty great thread like that anyway and I suppose it would
provide an emergency spare to get a bit of HW (with a quick wiring
swap) when, as is inevitable, the main element burns out at 6pm on
Christmas eve, as they're so often programmed to do......

On 16/05/10 23:45, GMM wrote:

Thanks Tim: Probably easier to get a second element than find a plug
for a dirty great thread like that anyway

http://www.bes.co.uk/products/103.asp

2 quid, down the bottom

having said that, a decent immersion heater is 10-15 squids or so.

Same BES page will give you an idea of lengths available. You'll
probably find what you need in B&Q or your nearest plumbing place.

and I suppose it would
provide an emergency spare to get a bit of HW (with a quick wiring
swap) when, as is inevitable, the main element burns out at 6pm on
Christmas eve, as they're so often programmed to do......

This is a valid point
--
Tim Watts

Hung parliament? Rather have a hanged parliament.

In article ,
GMM writes:
Thanks Tim: Probably easier to get a second element than find a plug
for a dirty great thread like that anyway and I suppose it would
provide an emergency spare to get a bit of HW (with a quick wiring
swap) when, as is inevitable, the main element burns out at 6pm on
Christmas eve, as they're so often programmed to do......

There's a special switch for this purpose...
http://www.mkelectric.co.uk/en-GB/Pr.../K5208WHI.aspx

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On May 16, 10:51*pm, GMM wrote:
I've just found that our hot water cylinder is weeping from the joint
between the body and the top. *Since it's over 40 years old (I
assume), it's probably simpler to replace than repair. *Now, I'm sure
there are rules about who can and can't do this, so let's assume that
I'm buying one and getting a plumber to fit it, in the same way as I
would never do anything electrical or with gas fittings (!).

The house has hot air heating (sadly), which means it's immersion
heater only for the DHW. *I have no intention of changing this as the
house is going onto the market soon and I don't want to start any new
major jobs.

Anyway, I've never played with hot tanks before but this is clearly a
direct cylinder. *Screwfix do what seems to be the best buy (http://www..screwfix.com/prods/49608...Cylinders/RM-D...
) but the description says it has a 'large heating coil', which sounds
wrong for a direct cylinder to me: *Is this a typo or am I missing
something?

The real question: *Does anyone know if the location of connections
(cold in, hot out, immersion heater) is standard? *If there's any
choice, I'll investigate the market to see what's the easiest fit.

Similarly, is there anything to consider in terms of immersion heater
elements? *I seem to recall reading that modern cylinders can have two
heater bosses and, presumably, this means they can be heated faster.
All the elements I can see (eg TLC) are 3kW: *Seems to me that 2 x 3kW
is too much for the existing 20A supply. *Does that mean I have to run
another 20A feed or is it reasonable to just cap one boss off? *(We've
got by for years with one element and I'd rather not have to feed it
with a new circuit if I can avoid it.)


This is silly. Just redo the joint.


NT

On 17/05/10 10:15, NT wrote:

This is silly. Just redo the joint.


NT

If it's weeping, it's pretty likely the rest is going to spring more
leaks real soon.

--
Tim Watts

Hung parliament? Rather have a hanged parliament.

On 17 May, 12:48, Tim Watts wrote:
On 17/05/10 10:15, NT wrote:

This is silly. Just redo the joint.

NT

If it's weeping, it's pretty likely the rest is going to spring more
leaks real soon.

--
Tim Watts

Hung parliament? Rather have a hanged parliament.

That was my thought: it seems that brazing or soldering would simply
chase the problem around the seam, possibly to a less visible position
(at least it's right at the front just now).
On the other hand, it occurred to me this morning that I might be able
to buy a little time by bodging something he I wonder if anyone's
had any luck with epoxy or any of the 'metal repair' filler?
Obviously would need draining down first but that's hardly a problem.

In article
s.com, GMM writes

On the other hand, it occurred to me this morning that I might be able
to buy a little time by bodging something he I wonder if anyone's
had any luck with epoxy or any of the 'metal repair' filler?

Given the potential for a big mess if the seam lets go, especially if
it's located on an upper floor, personally I wouldn't arse about with it
and would replace it asap.

--
(\__/)
(='.'=) Bunny's thinking about giving Windows 7
(")_(") a go despite what he's said about it...

On Tue, 18 May 2010 02:19:27 +0100, Mike Tomlinson
wrote:

In article
s.com, GMM writes

On the other hand, it occurred to me this morning that I might be able
to buy a little time by bodging something he I wonder if anyone's
had any luck with epoxy or any of the 'metal repair' filler?

Given the potential for a big mess if the seam lets go, especially if
it's located on an upper floor, personally I wouldn't arse about with it
and would replace it asap.


And take it to a few scrap metal merchants and ask them how much they
will pay for it. Older tanks have far more copper in them than new
ones, and the scrap value can be surprisingly high.

Normally, the plumber claims the scrap value and doesn't pass it on to
the customer.

On May 18, 2:19*am, Mike Tomlinson wrote:
In article
s.com, GMM writes

On the other hand, it occurred to me this morning that I might be able
to buy a little time by bodging something he *I wonder if anyone's
had any luck with epoxy or any of the 'metal repair' filler?

Given the potential for a big mess if the seam lets go, especially if
it's located on an upper floor, personally I wouldn't arse about with it
and would replace it asap.

Maybe I'm the only one that thinks the sensible thing is to have a
look at the joint first, see what the situation is, it may save a fair
bit of time & work.
Epoxy is good stuff, except when exposed to heat. If adhesive is
needed due to tank damage, better to go for one of the adhesives
designed for use on hot car engines.


NT

On Tue, 18 May 2010 01:13:07 -0700 (PDT), NT
wrote:

Maybe I'm the only one that thinks the sensible thing is to have a
look at the joint first, see what the situation is, it may save a fair
bit of time & work.


Yes, you probably are the only one. ;-)

Try concentrating your mind on the reality of the problem by
considering *the consequences* of a leak. Having had a leaking hot
water cylinder about four years ago which led to some fairly costly
damage, I would never consider taking a risk with a joint in an old
cylinder.

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember GMM saying
something like:

I wonder if anyone's
had any luck with epoxy or any of the 'metal repair' filler?

I've tried the repair types of epoxy putty and they're useless after a
few days. I suspect the expansion/contraction breaks the bond.

In article
s.com, NT writes

Maybe I'm the only one that thinks the sensible thing is to have a
look at the joint first, see what the situation is, it may save a fair
bit of time & work.

Each to his own, but IMO gluing a 40-year-old cylinder is not the most
wonderful idea. The cylinder owes the OP nothing.

--
(\__/)
(='.'=) Bunny's thinking about giving Windows 7
(")_(") a go despite what he's said about it...

On 18/05/10 18:18, Mike Tomlinson wrote:
In
s.com, writes

Maybe I'm the only one that thinks the sensible thing is to have a
look at the joint first, see what the situation is, it may save a fair
bit of time& work.

Each to his own, but IMO gluing a 40-year-old cylinder is not the most
wonderful idea. The cylinder owes the OP nothing.


Although changing a cylinder with one that's bound to have different
pipe locations fills me with horror (Helmut Kohl & Anne Widdecome
reclining naked on a glass coffee table kind of horror) I agree. *If* I
were trying to fix it I might patch some sheet copper on with plumbers
metal (as used for lead work) or even just blob some of the same on for
a small leak. But the heating is bound to disturb another weak bit and
so on... If it's pinholing, there may be potential holes blocked by
scale - once that falls off then :-

Much better to change it and be done with it. It's 40 years, it's had a
good life...

--
Tim Watts

Hung parliament? Rather have a hanged parliament.

On 18 May, 19:17, Tim Watts wrote:
On 18/05/10 18:18, Mike Tomlinson wrote:

In
s.com, *writes

Maybe I'm the only one that thinks the sensible thing is to have a
look at the joint first, see what the situation is, it may save a fair
bit of time& *work.

Each to his own, but IMO gluing a 40-year-old cylinder is not the most
wonderful idea. *The cylinder owes the OP nothing.

Although changing a cylinder with one that's bound to have different
pipe locations fills me with horror (Helmut Kohl & Anne Widdecome
reclining naked on a glass coffee table kind of horror) I agree. *If* I
were trying to fix it I might patch some sheet copper on with plumbers
metal (as used for lead work) or even just blob some of the same on for
a small leak. But the heating is bound to disturb another weak bit and
so on... If it's pinholing, there may be potential holes blocked by
scale - once that falls off then :-

Much better to change it and be done with it. It's 40 years, it's had a
good life...

--
Tim Watts

Hung parliament? Rather have a hanged parliament.

I think you're right - a new one is the only sensible thing, and no
messing about!

As much as I approach re-routing the old pipework with some
trepidation (3/4 to 22mm to god knows what and all the bends etc), it
can't possibly be as bad as that glass table can it? Can it? Oh
noooooo......

"GMM" wrote in message
...
I've just found that our hot water cylinder is weeping from the joint
between the body and the top. Since it's over 40 years old (I
assume), it's probably simpler to replace than repair. Now, I'm sure
there are rules about who can and can't do this, so let's assume that
I'm buying one and getting a plumber to fit it, in the same way as I
would never do anything electrical or with gas fittings (!).

The house has hot air heating (sadly), which means it's immersion
heater only for the DHW. I have no intention of changing this as the
house is going onto the market soon and I don't want to start any new
major jobs.

Replace it with a stainless steel cylinder. Some have 25 year guarantees.
Or fit a Rinnai multi-point water heater - can be fitted outside liberating
space in the house as no cylinder is needed. Then high pressure mains
showers. The Rinnai can have a flow switch fitted that cuts out the warm air
unit when the hot tap is on to keep the gas under a U6 meter consumption.

In time replace the warm air unit with a modern unit with an electrostatic
air filter. The difference is amazing. Much better than rads.

Prepare for the future.

On 18 May, 21:50, "Doctor Drivel" wrote:
"GMM" wrote in message

...

I've just found that our hot water cylinder is weeping from the joint
between the body and the top. *Since it's over 40 years old (I
assume), it's probably simpler to replace than repair. *Now, I'm sure
there are rules about who can and can't do this, so let's assume that
I'm buying one and getting a plumber to fit it, in the same way as I
would never do anything electrical or with gas fittings (!).

The house has hot air heating (sadly), which means it's immersion
heater only for the DHW. *I have no intention of changing this as the
house is going onto the market soon and I don't want to start any new
major jobs.

Replace it with a stainless steel cylinder. Some have 25 year guarantees.
Or fit a Rinnai multi-point water heater - can be fitted outside liberating
space in the house as no cylinder is needed. Then high pressure mains
showers. The Rinnai can have a flow switch fitted that cuts out the warm air
unit when the hot tap is on to keep the gas under a U6 meter consumption.

In time replace the warm air unit with a modern unit with an electrostatic
air filter. *The difference is amazing. *Much better than rads.

Prepare for the future.

Own goal, Drivel - try reading the OP's first post. He wants to sell
the house shortly, so clearly doesn't want to make any investment in
it for 25 years.

"robgraham" wrote in message
...
On 18 May, 21:50, "Doctor Drivel" wrote:
"GMM" wrote in message

...

I've just found that our hot water cylinder is weeping from the joint
between the body and the top. Since it's over 40 years old (I
assume), it's probably simpler to replace than repair. Now, I'm sure
there are rules about who can and can't do this, so let's assume that
I'm buying one and getting a plumber to fit it, in the same way as I
would never do anything electrical or with gas fittings (!).

The house has hot air heating (sadly), which means it's immersion
heater only for the DHW. I have no intention of changing this as the
house is going onto the market soon and I don't want to start any new
major jobs.

Replace it with a stainless steel cylinder. Some have 25 year guarantees.
Or fit a Rinnai multi-point water heater - can be fitted outside
liberating
space in the house as no cylinder is needed. Then high pressure mains
showers. The Rinnai can have a flow switch fitted that cuts out the warm
air
unit when the hot tap is on to keep the gas under a U6 meter consumption.

In time replace the warm air unit with a modern unit with an electrostatic
air filter. The difference is amazing. Much better than rads.

Prepare for the future.

Own goal, Drivel - try reading the OP's first post. He wants to sell
the house shortly, so clearly doesn't want to make any investment in
it for 25 years.


The Rinnai may be an investment pushing up the value of the house and
clearly making it more saleable, so a quick sale. The liberated space and
high pressure showers are a selling point. It is worth looking into.

Many are removing airing cupboards and extending their bathrooms, using
eternal Rinnais to gain the space.

In article
s.com, robgraham writes
.

Own goal, Drivel - try reading the OP's first post.

Usenet's write-only as far as dribble is concerned.

--
(\__/)
(='.'=) Bunny's thinking about giving Windows 7
(")_(") a go despite what he's said about it...

On 18 May, 19:17, Tim Watts wrote:
On 18/05/10 18:18, Mike Tomlinson wrote:

In
s.com, *writes

Maybe I'm the only one that thinks the sensible thing is to have a
look at the joint first, see what the situation is, it may save a fair
bit of time& *work.

Each to his own, but IMO gluing a 40-year-old cylinder is not the most
wonderful idea. *The cylinder owes the OP nothing.

Although changing a cylinder with one that's bound to have different
pipe locations fills me with horror (Helmut Kohl & Anne Widdecome
reclining naked on a glass coffee table kind of horror) I agree. *If* I
were trying to fix it I might patch some sheet copper on with plumbers
metal (as used for lead work) or even just blob some of the same on for
a small leak. But the heating is bound to disturb another weak bit and
so on... If it's pinholing, there may be potential holes blocked by
scale - once that falls off then :-

Much better to change it and be done with it. It's 40 years, it's had a
good life...

--
Tim Watts

Hung parliament? Rather have a hanged parliament.

So I did this job over the weekend and, surprisingly, it was far less
unpleasant than the Kohl/Widdecome scenario, apart from the fact that
the new cylinder (with fixed insulation) was wider so wouldn't fit
properly until I took the floor of the airing cupboard up and shifted
a pipe.
Much to my surprise, given the number of compression etc joints, the
only leak was from the immersion heater seal - Not a crossed thread
but it wouldn't tighten snugly against the cylinder. None of this was
down to skill, simply to extravagant use of Fernox LSX, which also
sealed the immersion heater - the best thing that's happened to
plumbing in the past 10 years, IMHO. A close second was the ratchet
pipe cutter from Wickes, which sorted all the cuts close to the
wall...except for the run of stainless pipe, which was a PITA (dealt
with using a jigsaw and a lot of swearing).

Thanks for all your tips.