No heating fault on a Y plan system Worcester Bosch boiler 15ri heat only wiring breakdown Bible

With silly season approaching 📚 Worcester Bosch 15ri heat only boiler combined with a Y plan system has no heating… Turned up to the job and the customers worried the heating won’t work come winter so first thing I do is check the programmer and roomstat is calling and then see what the boiler is doing.. The boiler is sat idle so it doesn’t even know there’s a demand.. I whip out the breakdown Bible to the no heating fault finding flow chart to make diagnosing this fault super easy.. I check for 240v on white… Then check for 240v on orange… New three port valve head required, so replace this on the first visit as this is standard van stock, customers now happy to have working heating ready for the cold months 🙏🏻