Is it possible to get or make a hot water cylinder that is not made
from metal? Around here they are usually copper. And thieves steal
anything that's made of copper, and they have just done so, together
with all the piping and taps.
The water is heated using a solar panel, so there is no electric
element or naked flames anywhere around the tank.
The water can reach boiling point.
I was thinking of some kind of plastic tank around 100 litres, in a
box packed with fibreglass insulation.

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

Is it possible to get or make a hot water cylinder that is not made
from metal? Around here they are usually copper. And thieves steal
anything that's made of copper, and they have just done so, together
with all the piping and taps.
The water is heated using a solar panel, so there is no electric
element or naked flames anywhere around the tank.
The water can reach boiling point.
I was thinking of some kind of plastic tank around 100 litres, in a
box packed with fibreglass insulation.

I'm no plastics expert, but have looked into this briefly regarding
using a large plastic tank for bulk hot water storage. From what I could
see, most easily/cheaply available plastics aren't much good above
80degC and it could be quite catastrophic if it lets go of a hundred or
a thousand litres of hot water. I was looking at HDPE primarily.

Your best bet might be to go for a stainless steel tank - it's worth
less than copper, but you'd pay for the making of it.
--
Dave
GS850x2 XS650 SE6a

"It's a moron working with power tools.
How much more suspenseful can you get?"
- House

On Thu, 9 Oct 2008 02:41:16 -0700 (PDT) someone who may be Matty F
wrote this:-

Is it possible to get or make a hot water cylinder that is not made
from metal?

Consolar make thermal stores out of plastic
http://www.consolar.co.uk/index.php?option=com_content&task=view&id=6&Itemid =15,
though if thieves realised how much they cost they might steal them
too. The cost is partly to do with the design to maximise
stratification.

A DIY hot water cylinder might be possible, but I would place it
where it cannot damage anyone if it fails. I assume you were
considering direct heating of the contents. Despite the claims of
some, indirect heating is best done with a coil designed for solar
(a long finned coil) rather than any old length of pipe.

100l is not a great amount of water for solar heating.

Where was the old cylinder/pipes/taps? Presumably in some
outbuilding.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

In article ,
Grimly Curmudgeon wrote:
I'm no plastics expert, but have looked into this briefly regarding
using a large plastic tank for bulk hot water storage. From what I could
see, most easily/cheaply available plastics aren't much good above
80degC and it could be quite catastrophic if it lets go of a hundred or
a thousand litres of hot water. I was looking at HDPE primarily.

Plenty cars use plastic for parts of their coolant system - and that can
reach temperatures well over 100C.

--
*Can fat people go skinny-dipping?

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" gurgled happily, sounding
much like they were saying:

I'm no plastics expert, but have looked into this briefly regarding
using a large plastic tank for bulk hot water storage. From what I
could see, most easily/cheaply available plastics aren't much good
above 80degC and it could be quite catastrophic if it lets go of a
hundred or a thousand litres of hot water. I was looking at HDPE
primarily.

Plenty cars use plastic for parts of their coolant system - and that can
reach temperatures well over 100C.

cough
Who mentioned kettles?

Matty F wrote:
Is it possible to get or make a hot water cylinder that is not made
from metal? Around here they are usually copper. And thieves steal
anything that's made of copper, and they have just done so, together
with all the piping and taps.
The water is heated using a solar panel, so there is no electric
element or naked flames anywhere around the tank.
The water can reach boiling point.
I was thinking of some kind of plastic tank around 100 litres, in a
box packed with fibreglass insulation.

You may be able to get a used galv steel tank. Add a big label saying
galvanised steel tank, 1963 and even if they can steal it they wont.
With a nice new shiny tank, once they've reached it they might take it
anyway, ss is worth something after all.


NT

"Matty F" wrote in message
...

Is it possible to get or make a hot water
cylinder that is not made from metal?
Around here they are usually copper.
And thieves steal anything that's made
of copper, and they have just done so, together
with all the piping and taps.

This is getting a "big" problem on building sites. One job I advised, a
renovation, I specced two combis with jigs avoiding cylinders. All hidden
pipe to be plastic with brass compression joints. No pipes were shown.
The pipes are just connected up to the combi jig and the combis safely
locked up.

The two combis did a bathroom each and one combi one floor's CH and the
other the other. The DHW outlets combine to fill the bath quickly. When
the system was installed the combis were in safe storage. Two wireless room
stat programmers were used and these removed (a simple 2 minute job) until
the day of hand-over. The combis were fitted to commission and then taken
away (a half days job), only being re-fitted on the day of hand-over.

I know of one job where the rads, cylinder and boiler were nicked. The
cylinder is what attracts them though. If they know there is none there and
pipes are plastic they will leave alone.

The two combis were cheaper than a system boiler, large cylinder, zone
valves and control gear. It was far quicker to fit as well.

Unfortunately that will not help you with a solar installation. Also, even
if you use the Consolar plastic cylinders (I think they have a range of
them, so check) , you have to let the thieves know that the cylinder is not
copper. They will not know that. Maybe a large sign on the cylinder saying
something like "Caution this is a plastic cylinder". Also, plastic pipes
are solar installations are not a good thing as they weaken dramatically
when over 100C.

On 9 Oct, 15:41, "Doctor Drivel" wrote:

Galvanized, but then the pipework should be galvanized or plastic.

Stainless steel, as in many unvented cylinders, less scrap value I
think but I haven't flogged any stainless so don't know. Many direct
gas fired water heaters and some unvented ones are 'glass-lined',
i.e., internally enamelled, with a sacrificial anode or electronic
corrosion prevention device.

Water softener pressure vessels are made of spiral wrapped GRP tape (I
think) but they mostly handle cold water. You can get softeners that
will soften hot water but I'm not sure what the tanks' material. I
also see a lot of commercial HWS storage cylinders abandoned in plant
rooms where the system has been changed over to an instantaneous plate
heat exchanger with a small storage vessel.

The thieves may cause most damage in smashing their way in and
smashing off pipes and insulation before they find it to be of little
scrap value. They are invariably intellectually challenged.

"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

Mary Fisher wrote:
"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.


unless its pressurised, at 10 PSI water boils at 115C at 40psi its 141C
not sure you could run a solar system in the UK at these temperature or
pressures though

--
Kevin R
Reply address works

In article ,
Mary Fisher wrote:
"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

I wouldn't be too sure if dribble installed the system.


--
Is the hardness of the butter proportional to the softness of the bread?*

Dave Plowman London SW
To e-mail, change noise into sound.

"Mary Fisher" wrote in message
t...

"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

All plastic pipe weakens with temperature rise. Solar systems can get overv
100C.

"Kevin" wrote in message
...
Mary Fisher wrote:
"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

unless its pressurised, at 10 PSI water boils at 115C at 40psi its 141C
not sure you could run a solar system in the UK at these temperature or
pressures though

Separate temperature and boiling point.

"Dave Plowman (News)" wrote in message
...
In article ,
Mary Fisher wrote:
"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

I wouldn't be too sure if dribble installed the system.

I hadn't allowed for that ...


--
Is the hardness of the butter proportional to the softness of the bread?*

YES!

Mary

"Doctor Drivel" wrote in message
...

"Mary Fisher" wrote in message
t...

"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

All plastic pipe weakens with temperature rise. Solar systems can get
overv 100C.

Examples?

On 9 Oct, 10:41, Matty F wrote:
Is it possible to get or make a hot water cylinder that is not made
from metal? *

Yes. Search for "Conus Solar" to see State Of The Art (and it ought
to be, at those prices!) in plastic tanks for use as a solar thermal
store.

On 9 Oct, 17:54, "Mary Fisher" wrote:

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

Well it would do, if you didn't have a Thermal Twin! Heatpipe systems
can and _will_ destroy plastic pipes of all commonplace "plastic"
materials short of the Aeroquip catalogue.

On Thu, 9 Oct 2008 17:54:21 +0100 someone who may be "Mary Fisher"
wrote this:-

water isn't going to get to over 100C by any system.

Water only boils at 100C under atmospheric pressure. Water can be
liquid, rather than steam at over 100C, if it is pressurised
sufficiently. The word water doesn't really convey the energy
contained in this stuff, it is best to think of it as liquid steam.
Systems of this type are in common use in industry and large scale
heating systems.

A solar system can approach these sorts of conditions when it
stagnates, though unless something is seriously wrong the water is
likely to turn to steam at a relatively early stage. However, there
is still a danger, though it is small due to the low volume of
pressurised water.

Incidentally the term for the temperature ranges in "ordinary"
heating systems is low temperature hot water. The term is as
dangerous for the uninitiated as the term low voltage in electrical
engineering. Low temperature hot water and low voltage electricity
are both dangerous.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

"Mary Fisher" wrote in message
t...

"Doctor Drivel" wrote in message
...

"Mary Fisher" wrote in message
t...

"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

All plastic pipe weakens with temperature rise. Solar systems can get
over 100C.

Examples?

Evacuated tube panels clearly can

"Mary Fisher" wrote in message
t...

"Dave Plowman (News)" wrote in message
...
In article ,
Mary Fisher wrote:
"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

If I say it can over 100c it can. Just take it as that.

"Dave Plowman (News)" wrote in message
...
In article ,
Mary Fisher wrote:
"Doctor Drivel" wrote in message
...

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

I wouldn't

Please eff off as you are a total idiot.

On Thu, 09 Oct 2008 21:39:08 +0100, David Hansen
wrote:

On Thu, 9 Oct 2008 17:54:21 +0100 someone who may be "Mary Fisher"
wrote this:-

water isn't going to get to over 100C by any system.

Water only boils at 100C under atmospheric pressure. Water can be
liquid, rather than steam at over 100C, if it is pressurised
sufficiently. The word water doesn't really convey the energy
contained in this stuff, it is best to think of it as liquid steam.

Latent heat?

Systems of this type are in common use in industry and large scale
heating systems.

snip

"Andy Dingley" wrote in message
...
On 9 Oct, 17:54, "Mary Fisher" wrote:

... plastic pipes are solar installations are not a good thing as they
weaken dramatically when over 100C.

It's not true of all plastic piping and water isn't going to get to over
100C by any system.

Well it would do, if you didn't have a Thermal Twin!

?

Heatpipe systems
can and _will_ destroy plastic pipes of all commonplace "plastic"
materials short of the Aeroquip catalogue.

'Commonplace' wasn't specified :-)

Mary

On Oct 10, 9:39 am, David Hansen
wrote:
On Thu, 9 Oct 2008 17:54:21 +0100 someone who may be "Mary Fisher"
wrote this:-

water isn't going to get to over 100C by any system.

Water only boils at 100C under atmospheric pressure. Water can be
liquid, rather than steam at over 100C, if it is pressurised
sufficiently. The word water doesn't really convey the energy
contained in this stuff, it is best to think of it as liquid steam.
Systems of this type are in common use in industry and large scale
heating systems.

A solar system can approach these sorts of conditions when it
stagnates, though unless something is seriously wrong the water is
likely to turn to steam at a relatively early stage. However, there
is still a danger, though it is small due to the low volume of
pressurised water.

The hot water tank was in a little box on top of the roof of a
mountain hut miles from any other residents.
Now that the tank is gone, there is steam coming out of the solar
panel, which is made from copper with a glass top. I don't know why
they didn't steal the panel as well, although it's rather heavy to
carry for 500 yards to the thieves truck.

If we decide we want to have hot showers again we will certainly wire
the hot water box up to the Screamer alarm on the roof which can be
heard for about a mile. Hopefully there will be a very deaf thief who
breaks his leg falling off the roof.

On Oct 10, 3:00 am, Adrian wrote:
"Dave Plowman (News)" gurgled happily, sounding
much like they were saying:

I'm no plastics expert, but have looked into this briefly regarding
using a large plastic tank for bulk hot water storage. From what I
could see, most easily/cheaply available plastics aren't much good
above 80degC and it could be quite catastrophic if it lets go of a
hundred or a thousand litres of hot water. I was looking at HDPE
primarily.
Plenty cars use plastic for parts of their coolant system - and that can
reach temperatures well over 100C.

cough
Who mentioned kettles?

Yes I have a plastic kettle that has lasted well for 15 years. I could
just buy 50 plastic kettles!
My car radiator is plastic and that is pressurised, so would exceed
100 degrees.
The tank is above a roof, so no problem if it leaks. The water
probably does not reach boiling point except when the tank is stolen,
but it's hot enough that we had to have a temperature limiting mixing
valve. The water is only used for a shower.

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "Dave Plowman (News)"
saying something like:

In article ,
Grimly Curmudgeon wrote:
I'm no plastics expert, but have looked into this briefly regarding
using a large plastic tank for bulk hot water storage. From what I could
see, most easily/cheaply available plastics aren't much good above
80degC and it could be quite catastrophic if it lets go of a hundred or
a thousand litres of hot water. I was looking at HDPE primarily.

Plenty cars use plastic for parts of their coolant system - and that can
reach temperatures well over 100C.



" most easily/cheaply available plastics"

"I was looking at HDPE primarily"
--
Dave
GS850x2 XS650 SE6a

"It's a moron working with power tools.
How much more suspenseful can you get?"
- House

On Fri, 10 Oct 2008 01:47:54 -0700, Matty F wrote:

The hot water tank was in a little box on top of the roof of a
mountain hut miles from any other residents.

If it's a one-off DIY job I'd look for a pre-loved GRP CW storage tank,
build a stout box around it and pack a load of skip-grade Kingspan and
glass/rockwool fibre or PU foam between the tank and the box (to partially
support, as well as insulate, the tank - I'm sure even GRP is weaker when
it's hot). And a lid, natch, insulated natch squared.

--
John Stumbles

The astronomer married a star

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

Plenty cars use plastic for parts of their coolant system - and that can
reach temperatures well over 100C.

cough
Who mentioned kettles?

Yes I have a plastic kettle that has lasted well for 15 years. I could
just buy 50 plastic kettles!
My car radiator is plastic and that is pressurised, so would exceed
100 degrees.

I was looking at easily available plastic tanks, barrels and drums of
60~200L in HDPE (think blue plastic) and IBC containers of 1000L (again,
white HDPE or similar).
Anything else will cost you or not be easily available or identifiable.
As for kettle or radiator plastic - for ****'s sake read what I wrote,
not what you think I wrote.
--
Dave
GS850x2 XS650 SE6a

"It's a moron working with power tools.
How much more suspenseful can you get?"
- House

On Oct 11, 8:31 am, John Stumbles wrote:
On Fri, 10 Oct 2008 01:47:54 -0700, Matty F wrote:
The hot water tank was in a little box on top of the roof of a
mountain hut miles from any other residents.

If it's a one-off DIY job I'd look for a pre-loved GRP CW storage tank,
build a stout box around it and pack a load of skip-grade Kingspan and
glass/rockwool fibre or PU foam between the tank and the box (to partially
support, as well as insulate, the tank - I'm sure even GRP is weaker when
it's hot). And a lid, natch, insulated natch squared.

Yes I think that or Grimly's HDPE should do the trick thanks.
We already have the box and glass fibre insulation.

John Stumbles wrote:
On Fri, 10 Oct 2008 01:47:54 -0700, Matty F wrote:

The hot water tank was in a little box on top of the roof of a
mountain hut miles from any other residents.

If it's a one-off DIY job I'd look for a pre-loved GRP CW storage tank,
build a stout box around it and pack a load of skip-grade Kingspan and
glass/rockwool fibre or PU foam between the tank and the box (to partially
support, as well as insulate, the tank - I'm sure even GRP is weaker when
it's hot). And a lid, natch, insulated natch squared.


Seems to me that if you foamed the void between tank and container fully
(expanding foam foamed in place, not bits) the outer, cold, container
would take the strain, not the hot inner.

ISTR this being used in the Haber process - the vessel is double walled,
the weak inner vessel protects the strong outer vessel from the
reactants, an inert gas being used between them to transfer the load.

Andy

On Oct 13, 7:07 am, Andy Champ wrote:

Seems to me that if you foamed the void between tank and container fully
(expanding foam foamed in place, not bits) the outer, cold, container
would take the strain, not the hot inner.

OK, so I'll look out for two containers, and use that expanding foam
stuff between them.
Perhaps I don't need a lot of insulation, and then the water won't
reach boiling point. It would be better to have a large tank at a
lower temperature.
We've never run out of hot water anyway. It costs nothing to heat it,
and the water is collected on the roof, going into a tank that holds
about 30 cubic metres.

"Matty F" wrote in message
...
On Oct 13, 7:07 am, Andy Champ wrote:

Seems to me that if you foamed the void between tank and container fully
(expanding foam foamed in place, not bits) the outer, cold, container
would take the strain, not the hot inner.

OK, so I'll look out for two containers, and use that expanding foam
stuff between them.
Perhaps I don't need a lot of insulation, and then the water won't
reach boiling point. It would be better to have a large tank at a
lower temperature.
We've never run out of hot water anyway. It costs nothing to heat it,
and the water is collected on the roof, going into a tank that holds
about 30 cubic metres.

30 cubic metres? Do you need that much hot water?

On Oct 13, 8:25 pm, "Doctor Drivel" wrote:
"Matty F" wrote in message

...

On Oct 13, 7:07 am, Andy Champ wrote:

Seems to me that if you foamed the void between tank and container fully
(expanding foam foamed in place, not bits) the outer, cold, container
would take the strain, not the hot inner.

OK, so I'll look out for two containers, and use that expanding foam
stuff between them.
Perhaps I don't need a lot of insulation, and then the water won't
reach boiling point. It would be better to have a large tank at a
lower temperature.
We've never run out of hot water anyway. It costs nothing to heat it,
and the water is collected on the roof, going into a tank that holds
about 30 cubic metres.

30 cubic metres? Do you need that much hot water?

That's just the cold water tank. Goodness knows why they got such a
large tank. However it was useful for the fire brigade when someone
burnt the original building down. At least it didn't set fire to the
trees as well.
The existing box on the roof would accommodate a 100 litre hot tank,
but we could rebuild it for a 200 litre tank. Or tell people to have
shorter showers. To hell with it, 20 minutes of shower is enough for a
hutload of people, 100 litres it is.

On 13 Oct, 05:16, Matty F wrote:

OK, so I'll look out for two containers, and use that expanding foam
stuff between them.

Expanding foam isn't a good insulator - different mechanical structure
to the factory-foamed stuff, much lower performance.

My solution to this (solar thermal store) is to switch from a round to
a rectangular plastic tank, then use a constructed box of yellow foam
PIR boards on the sides of it.

"Andy Dingley" wrote in message
...
On 13 Oct, 05:16, Matty F wrote:

OK, so I'll look out for two containers, and use that expanding foam
stuff between them.

Expanding foam isn't a good insulator - different mechanical structure
to the factory-foamed stuff, much lower performance.

And difficult to get into a restricted space.

My solution to this (solar thermal store) is to switch from a round to
a rectangular plastic tank, then use a constructed box of yellow foam
PIR boards on the sides of it.

A solution suggested to me by someone high up in such things is to build the
box round it and fill it with expanded polystyrene beads. It wouldn't be
perfect but it would be cheap and easy to do.

Nothing's perfect :-)

Mary

On Oct 13, 9:38 pm, Andy Dingley wrote:
On 13 Oct, 05:16, Matty F wrote:

OK, so I'll look out for two containers, and use that expanding foam
stuff between them.

Expanding foam isn't a good insulator - different mechanical structure
to the factory-foamed stuff, much lower performance.

My solution to this (solar thermal store) is to switch from a round to
a rectangular plastic tank, then use a constructed box of yellow foam
PIR boards on the sides of it.

Here's the box after the thieves wrecked it:
http://i33.tinypic.com/21dq645.jpg

Since it's square I guess a square tank would be sensible
There's about 360 litres of room there excluding insulation.

"Doctor Drivel" wrote:

"Matty F" wrote in message
...
On Oct 13, 7:07 am, Andy Champ wrote:

Seems to me that if you foamed the void between tank and container fully
(expanding foam foamed in place, not bits) the outer, cold, container
would take the strain, not the hot inner.

OK, so I'll look out for two containers, and use that expanding foam
stuff between them.
Perhaps I don't need a lot of insulation, and then the water won't
reach boiling point. It would be better to have a large tank at a
lower temperature.
We've never run out of hot water anyway. It costs nothing to heat it,
and the water is collected on the roof, going into a tank that holds
about 30 cubic metres.

30 cubic metres? Do you need that much hot water?


Does he need that much weight?

30 tonnes of water! I hope the foundations are built to take it.

On 10 Oct, 09:47, "Mary Fisher" wrote:

water isn't going to get to over 100C by any system.

Well it would do, if you didn't have a Thermal Twin!

?

Sorry, Solar twin, not Thermal twin.

If you had a heatpipe system instead, even compared to a vacuum tube
system with a water loop like the Solartwin, then you'd see much
higher output temperatures.

"Andy Dingley" wrote in message
...
On 10 Oct, 09:47, "Mary Fisher" wrote:

water isn't going to get to over 100C by any system.

Well it would do, if you didn't have a Thermal Twin!

?

Sorry, Solar twin, not Thermal twin.

If you had a heatpipe system instead, even compared to a vacuum tube
system with a water loop like the Solartwin, then you'd see much
higher output temperatures.

You need to brush up, Andy :-)

Mary

On Oct 14, 4:14 am, Bruce wrote:
"Doctor Drivel" wrote:

"Matty F" wrote in message
...
On Oct 13, 7:07 am, Andy Champ wrote:

Seems to me that if you foamed the void between tank and container fully
(expanding foam foamed in place, not bits) the outer, cold, container
would take the strain, not the hot inner.

OK, so I'll look out for two containers, and use that expanding foam
stuff between them.
Perhaps I don't need a lot of insulation, and then the water won't
reach boiling point. It would be better to have a large tank at a
lower temperature.
We've never run out of hot water anyway. It costs nothing to heat it,
and the water is collected on the roof, going into a tank that holds
about 30 cubic metres.

30 cubic metres? Do you need that much hot water?

Does he need that much weight?

30 tonnes of water! I hope the foundations are built to take it.

The large cold water tank is on the ground uphill from the building.
There's a small cold water tank on the ground below the building fed
by rainwater from the roof. Water is automatically pumped to the large
tank when the level drops.