Jim GM4DHJ ... wrote:
On 23/08/2019 14:35, Jim GM4DHJ ... wrote:
On 23/08/2019 12:16, Max Demian wrote:
On 23/08/2019 10:21, Harry Bloomfield wrote:
Andrew laid this down on his screen :
The high pressure pipelines apparently
are the 'storage' for a quite a while because of the enormous pressures
involved.

Plus underground storage.

Its potentially dangerous to turn gas supplies off. Some older
appliances lack a flame failure and would spew gas out if it came
back on, with the appliance left on.

I thought they always had a bimetallic strip heated by the (pilot) flame.

used to be only caravans
no sorry I meant dwelling flats ...sorry...but caravans as well ....no
idea the logic behind that...things may have changed ... new cookers may
now all have them......much safer

'Flame Failure' device. They're mandatory on caravan and boat cookers
certainly, I'm not sure about ordinary domestic ones though it would
make a lot of sense. I've occasionally missed a burner turned on but
not alight on our hob.

The ones I've come across (boat installed hobs) have thermocouples
rather than bimetallic strip (which I take to be a 'clicky' type
thing). The thermocouple generates enough voltage/current to hold a
small solenoid valve open. Working this way means it's pretty fail
safe unless the valve sticks open. They do occasionally fail the
other way though, failing to stay open when you release the manual
override for turning on.

--
Chris Green
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