On 26/08/2020 19:20, Stephen wrote:
Thank you. What is the advantage of using a flexible hose? I
assumed this would perish over time due to the heat? I thought
most boiler manufacturers specified copper only within a metre of
the boiler? Thanks again!

But as I said, you don't need to be that close to the boiler. External
vessels usually hang on a bracket to keep the weight off the pipework.
Having a flexible hose makes it easier to connect. Mine is tucked up
quite close to the boiler so there is not much room around the Schraeder
valve. By unhooking it, it becomes easy to attach a pressure gauge or a
hose from a bicycle pump. Also, if I do want to depressurise it to check
the pressure, by unhooking it from the bracket and swinging it out from
the wall it is easier to direct the drain valve outlet into a suitable
bucket.

I'm not sure what type of rubber is used in these hoses but I've never
had one fail. They are mechanically well protected by the mesh which
stops them getting kinked; a common failure mechanism for rubber is
attack from UV or ozone which is always worse at stressed regions. And a
dead leg like this (or a filling loop) will never get very warm from the
water side even if it goes into the boiler outlet pipe.