On 2 Dec, 17:13, fred wrote:
In article , Tim Downie
writes



John Rumm wrote:

I think there is another misconception here as well. The only time a
pressurised water cylinder is at explosion risk is going to be when it
has the possibility of being heated to over the boiling point of the
water content. Then there is the risk of the explosive production of
steam should it rupture.
For a cylinder heated via a water flow from a boiler, the chances of
super heating it seem minimal.

You're forgeting Sods law. *The only time the safety valve is likely to get
stressed is when your CH boiler packs up on Christmas Eve and you turn on
the immersion element that's not been used in years. *A sticky stat in that
and a sticking safety valve can then lead to an explosive situation. *A
vented cylinder needs another level of system failure before it can blow..

So, just to summarise, for an unvented cylinder to be at risk of over
pressure failure following oveheating:

a) The immerser must be in use and the stat fail
and
b) The manditory overheat stat must fail
and
c) The manditory over pressure relief valve must fail

Still scared?
--
fred
BBC3, ITV2/3/4, channels going to the DOGs- Hide quoted text -

- Show quoted text -

You forgot the mandatory overtemperature relief valve!