Does anyone have any comments on whether regular descaling of a kettle
causes surface damage that can make it more susceptible to limescale
in the future?

We use one of those knitted wire thimble things in the kettle.

So long as you wash it out every couple of months, it totally solves
the scale problem.

Our kettle is about ten years old and the inside is perfectly clean,
but previous kettles have been badly furred up within just a few months
use.

On Tue, 02 Aug 2005 23:03:36 +0100, Peter
wrote:

Does anyone have any comments on whether regular descaling of a kettle
causes surface damage that can make it more susceptible to limescale
in the future?

Use filtered water.

On 2 Aug 2005 17:17:54 -0700, wrote:

We use one of those knitted wire thimble things in the kettle.

So long as you wash it out every couple of months, it totally solves
the scale problem.

Our kettle is about ten years old and the inside is perfectly clean,
but previous kettles have been badly furred up within just a few
months use.

Your water isn't particulary hard if it takes a few months to become
baddly furred, either that or you don't use the kettle that much. B-)

In a real hardwater area a kettle becomes badly furred in a few weeks.
Our rapid boil kettel would start to trip on the safety cut out if it
wasn't descaled every 5 weeks or so. The water Co changed the source
of our water about a year ago, from a local adit to a reservior in the
next vally. Haven't descaled the kettle since and there is virtually
no scale in there, pity about the brown stain, presumably from peat.

The knitted metal ball things do help with only mildly hard water and
are easier to clean, just scruch up under running water. But with
really hard water I doubt that it would make much difference.

--
Cheers
Dave. pam is missing e-mail

"Peter" wrote in message

Does anyone have any comments on whether regular descaling of a kettle
causes surface damage that can make it more susceptible to limescale
in the future?

Properly formulated kettle de scaler will be 'buffered' to reduce it's
effect on anything other than limescale. Ordinary acids not specifically
intended for this purpose may also attack other items.

Dave

Does anyone have any comments on whether regular descaling of a kettle
causes surface damage that can make it more susceptible to limescale
in the future?

Use filtered water.
Filtering water cannot remove dissolved ionic salts.

Mr F

Does anyone have any comments on whether regular descaling of a kettle
causes surface damage that can make it more susceptible to limescale
in the future?

Oddly enough, it is more likely that _using_ it has that effect. For
the scale to form the minerals (normally calcium/magnesium carbonate
plus a touch of silica) need a nucleation site to begin to form their
crystals on. once a seed crystal is formed, it will continue to grow as
long as there is available saturated solution. I have not got my
reference book to hand, but I think all three minerals have a positive
solubility coefficient i.e. they are more soluble in hot water than
cold. If the kettle cools with boiled water in it further
crystallisation will take place This is how Travertine marble (really a
limestone) is formed by hot springs. The buff squiggly stone on the
front of a certain very litigious burger chain is this rock. But I
digress.

When you boil water it cavitates i.e. a bubble forms and collapses. The
collapse is violent, so violent in fact that it can damage metal.
Eventually the bottom of the kettle will be microtextured, with myriad
nucleation points. If the cavitation is bad enough, it can, over time,
erode metal. If you try to put too much shear stress on water
cavitation occurs. I once the impeller of a Francis turbine
(hydrelectric use, water powers the turbine) which had been in service
for 20 years. A quite staggering amount of bronze (15%?) had been
removed. Cavitation also affects ships propellers, which keeps bronde
foundries in business. If the propeller is run grossly too fast the
cavitation can get to the stage where almost the entire propeller is a
cloud of cavitated water and the efficiency is greatly reduced.

Finally, should you wish to see nucleation points in action, buy
yourself a pint of fizzy cider or lager. When it was settled examine
the liquid near the side of the glass. Do you see a stream of little
bubbles heading to the surface? They are all coming fron the same
point. That is a nucleation point.

John Schmitt

In article ,
Mr Fizzion writes:
Does anyone have any comments on whether regular descaling of a kettle
causes surface damage that can make it more susceptible to limescale
in the future?

Use filtered water.
Filtering water cannot remove dissolved ionic salts.

Well, all the 'filter' jugs contain ion-exchange softeners as
well as filters, so they do in practice exchange out the salts
which cause hard water.

--
Andrew Gabriel

Nice chemistry/physics post John

To the point g

Dave

Your water isn't particulary hard if it takes a few months to become
baddly furred, either that or you don't use the kettle that much. B-)

If you go to www.calgon.co.uk there is a little box where you can enter your
postcode and it tells you how hard the water is!

Dave

David Lang wrote:
If you go to www.calgon.co.uk there is a little box where you can enter your
postcode and it tells you how hard the water is!


Only, I'm afraid it doesn't seem to be very accurate..... erring on the side
of "Please buy more Calgon" even for postcodes that I know don't have hard
water.

Rob

Rob Summers wrote:
David Lang wrote:

If you go to www.calgon.co.uk there is a little box where you can enter your
postcode and it tells you how hard the water is!



Only, I'm afraid it doesn't seem to be very accurate..... erring on the side
of "Please buy more Calgon" even for postcodes that I know don't have hard
water.

Rob


Mine, it claimed was a medium level area, and recommended Calgon for
every wash to avoid damaging the washing machine.

Hmmm

9 year old kettle - no scale

Washing machine packed up after 6 years - entirely due to a slipped
belt, which snagged the wiring loom and in repairing it, I knackered the
level sensor; New washing machine = 3 years and going strong.

Pinch of Salt?

On Wed, 03 Aug 2005 18:37:35 +0100, Mike Dodd wrote:

If you go to www.calgon.co.uk there is a little box where you can
enter your postcode and it tells you how hard the water is!

Only, I'm afraid it doesn't seem to be very accurate..... erring on
the side of "Please buy more Calgon" even for postcodes that I know
don't have hard water.

Mine, it claimed was a medium level area, and recommended Calgon for
every wash to avoid damaging the washing machine.

I got " Soft Sorry, we do not recommend using Calgon for soft water
areas." Sorry? I'm not but I guess they are... I'd have expected
medium if they had data for the old supply not the new.

I did notice that the full entered post code changed to just district
level (the first half) when I clicked submit. Bunging in the same full
postcode but without the central space gets " Not Available. We're
sorry! There are no records for your location, if in doubt use Calgon
in every wash."

So it looks like they are doing it on district sized areas and the
page coding can't cope with a postcode without the space. The area is
to large and the page coding hasn't been properly tested.

--
Cheers
Dave. pam is missing e-mail