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newshound newshound is offline
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Default Unvented system confusion.

On 16/08/2018 20:48, Chris B wrote:
On 16/08/2018 20:44, Tim+ wrote:


The hot water system is just a €śthrough the boiler/heat exchanger€ť system
so just turn off cold inlet to boiler, change washer, job done.


No, its the 185 lt of hot water in the pressurised cylinder I'm worried
about......


Tim



The great thing about it being a *tap* is that you can just open it to
check that you have managed to isolate it without causing a flood.

Exactly what you have to turn off depends on whether the cylinder is
pressurised by the rising main, or by a header tank. But you
*definitely* should have some some way of isolating it, without having
to drain down all that hot water. If not, then this is the time to add a
service valve. Often the easiest way is with something like this:

https://www.screwfix.com/p/flexible-...-x-300mm/3558g

since you then don't have to do any "precision" plumbing.