DH is a Gas safe heating engineer. He has access to pretty much every boiler’s manufacturer’s instruction/fault finding manuals to help you narrow down the issue , so pm me if you want a bit of free advice. Obviously evenings are when you will get a reply.
there are some cowboys out there - when contacting a gas engineer you should ALWAYS check the gas safe register first, which includes an up to date photo 😉
If you are in Staffordshire /South Cheshire and need Domestic gas
( not oil or Lpg) boiler related stuff doing / fixing then you can pm me.
I won’t be advertising his details here.