I don't recall their name, will have to look it up. They were the only authorised repairer here. They told me nothing at all! They just took my money.
Kinda looks like one of the valves (the top left of the 4) was replaced as it is a slightly different shade of grey to the others so maybe that's all they did.
So if no-one here has any ideas does anyone know who I can ask?
Thanks,
Sarah