When to read the dial??

[Aquaman]

When I said easy.....perhaps I should of said could I do it with my basic plumbing skills if I bought the part?

Boiler is a Worcester Bosch 28i junior

 

[Aquaman]

Also, today's new symptom is when the toilet cistern finishes filing....there is rather strangely a loud clunk coming from inside the boiler....is this related to my problems?????

 

[Phill Peck]

Do you have incredibly high water pressure

 

[Aquaman]

it does seem really powerful(there's noway you could have a tap on full for example)....but I've no way of testing