I am having a system boiler with a pressurised water cylinder installed by a
I've just noticed on the cylinder it says that I should inform Building
Why? I'm not looking for unnecessary fees to pay.
Er... because it's the law.
They have to be installed by appropriately qualified fitters (ie not
just a bog-standard CORGI). If not done properly, with all the
appropriate safety features etc, they have the potential to be extremely
Interesting link. There is no issue with my plumbers qualifications.
My question was why does B.control need to know? Do they have to be informed
every time a gas appliance is installed etc. A gas bang will make that one
on you-tube look like a cheap firework.
Sure, take an unvented cylinder, and :
1) weld up all the inlets/outlets/safety vents;
2) bypass all the thermal input controlls
then you have an issue.
But you have the same issue with an unvented system.
Weld up the inlet /outlet /vent pipe and bypass the thermal controlls and
In either case its not a realistic scenario.
Yes..I think you are simply supposed to ge a signed off bit of paper
saying its been installed to spec and tested properly and send a copy
to building control.
OTOH as lg as it has been done to spec, and you have tat pare, and dont
tell BCO othg bad will happen.
At the worst we you want to sell some stupid lawyer will want to see all
the bits of paper.
AFAIK BCO powers are limited to making you take out or redo work that is
not to spec. He has no powers to fine you for failure to notify if work
is found to be to spec
The worst that can happen is somehow he gets to know and says 'I want a
fully signed off test on that installation or take it out'
Of late we (the population of this country and especially people in
construction and building services) have been subject to a large number of
extra regulations. I'd personally go for less rules and more enforcement.
Even replacing a VENTED hot water cylinder is a notifiable activity.
So also is adding an electric socket in a kitchen.
Any person qualified to install an UNVENTED cylinder (a good proportion of
heating engineers will be qualified) has the option to notify building
control via their guild (CORGI in this case). The cost of this is likely
to be £2.50 as oppose to over £100 if you do it yourself. What's more
unvented cylinders are not permitted to be fitted by anyone who is not
On 17 Nov, 22:46, "Ron Lowe"
It does happen, usually if someone finds the safety valve is dripping
and plugs the pipe. Or if it is installed by someone who doesn't know
what they're doing. Thermostats frequently fail by the contacts
welding themselves together.
It is rare enough that it has the status of an urban myth. It has
never yet happened with an unvented system in the UK. In the US they
only have one safety valve fitted.
Drivel used to post the waterheaterblast.com link; he always claimed
they were unsafe and advocated thermal stores, but he is a moron.
I agree to an extent (and I have an unvented cylinder myself), but the
above is a completely unfair comparison... a vented cylinder is
*designed* to operate not under pressure, so far a start if, it was
welded up and pressurised, it would go 'pop' at a much lower pressure
than an unvented one - sure, a nasty bang, but nothing like the one in
the video clip.
And since an unvented cylinder is designed to be pressurised, it doesn't
need welding up to produce a fault situation: that could be achieved by
a complete moron installing it wrongly without all the appropriate
safety valves etc.
store, and moreso heat banks, are a much better option, especially
integrated ones that also run the CH off them. About the same price as an
unvented cylinder yet offer far, far more.
If the OP has bought an unvented cylinder I would advise he takes it back
and gets a heat bank (Range Cylinders call them thermal stores). The
advantages are tenfold.
It is designed to operate under pressure. IT IS NOT at atmospheric pressure
as is a venetd thermal sgtore or heat bank.
Before you write this sort of stuff just ask me first.
An unvented cylinder can bring down the side of a house and few in the UK
The exercise was to show what can happen if they fail. Anyone with common
sense can see that. Murphy's Law says that if it can happen, it will
OK, you know what I mean - it operates under the small head of pressure
generated by the cold water tank; which is a completely different ball
game to an unvented system which has to cope with mains pressure.
Thanks for the advice - I'll take that under consideration...
A water heater exploded in the block of flats I used to live in - it
took out most of the partitions walls and most of the windows in the
flat in which it happened. It had been leaking alot and we suspect
that someone blocked up a safety valve to stop the leak.
AFAIU local council can choose to not allow unvented systems but I
would think that would be unlikely. Thus, I think you need approval
before the work begins.