On 2 Dec, 15:58, Andy Dingley wrote:
On 2 Dec, 15:10, John Rumm wrote:

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.

Not true. It's a pressurised system with an air reservoir. If
punctured, it will spray hot water at system pressure in a way that
vented systems won't. That's itself a hazard (depending on location).

Any central heating system capable of sinking a trawler (look it up!)
needs some degree of care in its maintenance.

The point, that annual certificated inspection of unvented hot water
tanks (at £50+ a pop) is not mandatory. I had been mislead into
thinking was is by people trying to sell me a thermal store. Being
lied to irritates me!

It is non sequitur to assume no checking or maintenance will be done.
I can assure you (never having had one of these things before) my
checking will be daily for quite some time after installation, even
knowing that there must be literally millions of the systems installed
safely across Europe, and that mine (with its internal expansion
chamber) is guaranteed for 25 years.

I will take your advice however, and refrain from attacking it with an
axe!

T