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The Natural Philosopher[_2_] The Natural Philosopher[_2_] is offline
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Default Where does air come from in a sealed heating system?

On 01/03/17 14:00, Tim Lamb wrote:
In message , Bob Eager
writes
On Wed, 01 Mar 2017 12:11:16 +0000, charles wrote:

In article ,
Tim Lamb wrote:
In message , Harry Bloomfield
writes
Tim Lamb was thinking very hard :
And quite right too. The switch contacts are designed to break the
current cleanly. The pin contacts may suffer a series of arcs
leading to pitting and degradation. In the worst case heating such
that the Beryllium copper contacts lose their *spring*.

Were the sockets not designed to break the current, then all sockets
would be fitted with switches.

Worst case is domestic staff switching off kettles by lifting the
jug
from the base as you might from a kitchen range!

I do that too. They have a switch in the base to swith the supply when
the kettle is lifted. Even if the base switch does eventually fail, by
then the kettle will need to be replaced. They are not expensive these
days.

I'm not sure if you can purchase an unswitched 13 Amp socket these days

[Snip]

According to TLC's catalogue Contactum make them.


And MK.


OK chaps. You can buy them! Would you?

Oh yes. In some application they are ideal, when you don't want anything
accidentally switched off

Like a washing machine or a fridge
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