So boiler broke, veissmann, damn good and lots less than vailant and Bosch the Audi and BMW of boilers. Won’t bore you with detail, but couldn’t get a plumber at short notice but rather than just say No booked solid like the rest, PK Plumbing of Reading said ‘what’s wrong’ then proceeded to diagnose by text over course of about 1.5hrs, telling me what to check. Then sold me the required part via his missus, at trade price. Just a worn sparj ignitor.
Bloke clearly knew his stuff and obviously more than fair. Even refused a bottle for his trouble (I gave his missus some fizz anyway).
Sooooo, I heartily recommend him, just Google.