Currently taking the CH apart and updating various things. The system
and pipework are over 30 years old and we live in a very hard water
area.

Had to remove a section of incoming main (15mm) and to my astonishment
it was virtually limescale free. There was a very fine layer of
powdery limescale but you could wipe this off with a finger.

Also, removing a section of pipework from the radiator circuit showed
that to have only a very fine layer of magnetite. The water removed
from the rads had a slight dark "tinge" to it but nothing severe.

The pipework genuinely hasn't been touched in 30+ years. The previous
owner stated that he did nothing to the CH system apart from hoover
the boiler out every year.

I'm starting to think all this stuff about limescale blocking pipes is
a load of rubbish.

Kettles and appliances yes (I have seen that) but pipework no..I
assume heat makes the difference?

Has anyone any first hand experience of pipework becoming seriously
scaled up or is it a myth?

Can anyone explain why my 30 year old pipework is scale free?

sponix

On Mon, 09 Jan 2006 14:03:02 GMT, (sPoNiX) wrote:

Currently taking the CH apart and updating various things. The system
and pipework are over 30 years old and we live in a very hard water
area.

Had to remove a section of incoming main (15mm) and to my astonishment
it was virtually limescale free. There was a very fine layer of
powdery limescale but you could wipe this off with a finger.

Also, removing a section of pipework from the radiator circuit showed
that to have only a very fine layer of magnetite. The water removed
from the rads had a slight dark "tinge" to it but nothing severe.

The pipework genuinely hasn't been touched in 30+ years. The previous
owner stated that he did nothing to the CH system apart from hoover
the boiler out every year.

I'm starting to think all this stuff about limescale blocking pipes is
a load of rubbish.

Kettles and appliances yes (I have seen that) but pipework no..I
assume heat makes the difference?

Has anyone any first hand experience of pipework becoming seriously
scaled up or is it a myth?

Can anyone explain why my 30 year old pipework is scale free?

sponix

Depends where you live. Some parts of Wales have lovely soft water,
London has cement in the pipes.

On Mon, 09 Jan 2006 14:03:02 GMT, (sPoNiX) wrote:

Currently taking the CH apart and updating various things. The system
and pipework are over 30 years old and we live in a very hard water
area.

Had to remove a section of incoming main (15mm) and to my astonishment
it was virtually limescale free. There was a very fine layer of
powdery limescale but you could wipe this off with a finger.

Also, removing a section of pipework from the radiator circuit showed
that to have only a very fine layer of magnetite. The water removed
from the rads had a slight dark "tinge" to it but nothing severe.

The pipework genuinely hasn't been touched in 30+ years. The previous
owner stated that he did nothing to the CH system apart from hoover
the boiler out every year.

I'm starting to think all this stuff about limescale blocking pipes is
a load of rubbish.

Kettles and appliances yes (I have seen that) but pipework no..I
assume heat makes the difference?

Has anyone any first hand experience of pipework becoming seriously
scaled up or is it a myth?

Can anyone explain why my 30 year old pipework is scale free?

sponix

You wouldn't expect to find scale in the cold water pipes. If you
think about it, if that were to happen, all the street mains would be
in severe trouble by now. The calcium and magnesium compounds in
scale come out of solution on heating and generally on the heating
surfaces, so you would expect to find it on the surfaces of the coil
inside the HW cylinder and possibly inside some of the pipes in the
near vicinity. On older systems with a direct cylinder where there
is no coil and the DHW circulates by convection through the boiler,
you would expect to find scaling of the boiler and pipework from it.

The water in the heating circuit seldom changes, so no significant
scaling there. If the system doesn't have problems with pumping over
or sucking down because of pump placement and pipework, then initial
dissolved oxygen, causing corrosion would be used up.

You might find that if you check the radiators, there is more
magnetite in these since the water is crossing radiators at a lower
speed at a given point than it will be through the pipes feeding them.
Hence material is deposited, typically in a triangular shape at the
bottom.


--

..andy

"sPoNiX" wrote in message
...
Currently taking the CH apart and updating various things. The
system
and pipework are over 30 years old and we live in a very hard water
area.

Had to remove a section of incoming main (15mm) and to my
astonishment
it was virtually limescale free. There was a very fine layer of
powdery limescale but you could wipe this off with a finger.

Also, removing a section of pipework from the radiator circuit
showed
that to have only a very fine layer of magnetite. The water removed
from the rads had a slight dark "tinge" to it but nothing severe.

The pipework genuinely hasn't been touched in 30+ years. The
previous
owner stated that he did nothing to the CH system apart from hoover
the boiler out every year.

I'm starting to think all this stuff about limescale blocking pipes
is
a load of rubbish.

Kettles and appliances yes (I have seen that) but pipework no..I
assume heat makes the difference?

Has anyone any first hand experience of pipework becoming seriously
scaled up or is it a myth?

Can anyone explain why my 30 year old pipework is scale free?

sponix

Incoming main is cold - the lime tends to come out when warm.

C/H pipes - so long as system isn't constantly emptying and filling
you only have the lime held in 'one fill' of the system to deposit on
the pipes so not much should be there.

On the other hand the domestic hot water pipes and inside of the hot
cylinder I would expect to be encrusted in limescale.

AWEM

sPoNiX wrote:
Currently taking the CH apart and updating various things. The system
and pipework are over 30 years old and we live in a very hard water
area.

You can check your water hardness by entering your post code into a box on
www.calgon.com I have checked this with areas I know to be hard & softa
water and it hasn't failed yet.


Kettles and appliances yes (I have seen that) but pipework no..I
assume heat makes the difference?

It does indeed, at about 70 centigrade the calcium (mainly) salts come out
of solution and stick to metal items like pipes.

Has anyone any first hand experience of pipework becoming seriously
scaled up or is it a myth?

Sure can. Industrial high pressure hot water cleaner 160 bar @20 litres/min
I once installed in Gosport, Hants scaled up sufficiently to almost block a
10mm pipe completely - did it in less than a fortnight and kept doing it.
We added a chemical scale inhibitor, reduced the heat to below 70 c and made
the operator run it cold before stopping use. This didn't stop the problem,
just reduced it a lot.

Can anyone explain why my 30 year old pipework is scale free?

The cold would be, the calcium salts stayed in solution. With the hot, once
the scale had come out of the original fill water, that's it.

Dave

On Mon, 09 Jan 2006 14:38:08 +0000, Andy Hall
wrote:

You wouldn't expect to find scale in the cold water pipes. If you
think about it, if that were to happen, all the street mains would be
in severe trouble by now. The calcium and magnesium compounds in
scale come out of solution on heating and generally on the heating
surfaces, so you would expect to find it on the surfaces of the coil
inside the HW cylinder and possibly inside some of the pipes in the
near vicinity. On older systems with a direct cylinder where there
is no coil and the DHW circulates by convection through the boiler,
you would expect to find scaling of the boiler and pipework from it.

The water in the heating circuit seldom changes, so no significant
scaling there. If the system doesn't have problems with pumping over
or sucking down because of pump placement and pipework, then initial
dissolved oxygen, causing corrosion would be used up.

You might find that if you check the radiators, there is more
magnetite in these since the water is crossing radiators at a lower
speed at a given point than it will be through the pipes feeding them.
Hence material is deposited, typically in a triangular shape at the
bottom.

I'll check the cylinder when it comes out and see if it's more scaley.

sponix

In . uk,
david lang scribed:

You can check your water hardness by entering your post code into a box on
www.calgon.com I have checked this with areas I know to be hard & softa
water and it hasn't failed yet.

snipped

Thanks for this.

Nigel

david lang wrote:
sPoNiX wrote:
Currently taking the CH apart and updating various things. The system
and pipework are over 30 years old and we live in a very hard water
area.

You can check your water hardness by entering your post code into a box on
www.calgon.com I have checked this with areas I know to be hard & softa
water and it hasn't failed yet.


Hmm. I beg to differ. Out of three postcodes of which I tried and which I
know the hardness of the water it managed a not too amazing 1 out of 3.

Rob

Rob Summers wrote:
david lang wrote:
sPoNiX wrote:
Currently taking the CH apart and updating various things. The
system and pipework are over 30 years old and we live in a very
hard water area.

You can check your water hardness by entering your post code into a
box on www.calgon.com I have checked this with areas I know to be
hard & softa water and it hasn't failed yet.


Hmm. I beg to differ. Out of three postcodes of which I tried and
which I know the hardness of the water it managed a not too amazing
1 out of 3.

Rob

Rob,

If you mean it didn't recognise two of the post codes - I had the same
problem.

It would appear that their post code database is (shall we say) a little out
of date. Ours changed about 10 years ago from NP1 to NP11 and I had to
input the old one to get a result - a soft water area, which I already knew.

Brian G

"david lang" wrote in message
. uk...
sPoNiX wrote:
Currently taking the CH apart and updating various things. The system
and pipework are over 30 years old and we live in a very hard water
area.

You can check your water hardness by entering your post code into a box on
www.calgon.com I have checked this with areas I know to be hard & softa
water and it hasn't failed yet.

snip

If you check your local water co website it will tell you the hardness of
your water without bias ( they have no product to sell )

Regards Jeff

Regards Jeff

On Mon, 09 Jan 2006 14:03:02 +0000, sPoNiX wrote:

Currently taking the CH apart and updating various things. The system
and pipework are over 30 years old and we live in a very hard water
area.

Had to remove a section of incoming main (15mm) and to my astonishment
it was virtually limescale free. There was a very fine layer of
powdery limescale but you could wipe this off with a finger.

Also, removing a section of pipework from the radiator circuit showed
that to have only a very fine layer of magnetite. The water removed
from the rads had a slight dark "tinge" to it but nothing severe.

The pipework genuinely hasn't been touched in 30+ years. The previous
owner stated that he did nothing to the CH system apart from hoover
the boiler out every year.

I'm starting to think all this stuff about limescale blocking pipes is
a load of rubbish.

Kettles and appliances yes (I have seen that) but pipework no..I
assume heat makes the difference?

Has anyone any first hand experience of pipework becoming seriously
scaled up or is it a myth?

Can anyone explain why my 30 year old pipework is scale free?

Your system was in good order.

Where new water is being frequently added to the circuit scale can be a
problem and corrosion due to the dissolved oxygen.

Posts and replies here are often dealing with troubles causes by problems
which you simply have not had.



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://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
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

On Mon, 09 Jan 2006 15:48:44 +0000, sPoNiX wrote:

On Mon, 09 Jan 2006 14:38:08 +0000, Andy Hall
wrote:

You wouldn't expect to find scale in the cold water pipes. If you
think about it, if that were to happen, all the street mains would be
in severe trouble by now. The calcium and magnesium compounds in
scale come out of solution on heating and generally on the heating
surfaces, so you would expect to find it on the surfaces of the coil
inside the HW cylinder and possibly inside some of the pipes in the
near vicinity. On older systems with a direct cylinder where there
is no coil and the DHW circulates by convection through the boiler,
you would expect to find scaling of the boiler and pipework from it.

The water in the heating circuit seldom changes, so no significant
scaling there. If the system doesn't have problems with pumping over
or sucking down because of pump placement and pipework, then initial
dissolved oxygen, causing corrosion would be used up.

You might find that if you check the radiators, there is more
magnetite in these since the water is crossing radiators at a lower
speed at a given point than it will be through the pipes feeding them.
Hence material is deposited, typically in a triangular shape at the
bottom.

I'll check the cylinder when it comes out and see if it's more scaley.

An inch or two of flakey stuff is quite common after 20 years.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://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
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html