Just been to see an elderly customer and need a bit of advise. She has a Baxi boiler that has the fault flashing of Lt, which according to the manual indicates a problem with the DHW Switch. Does anyone know a rough cost for this part and can it be replaced by a corgi registered or is it a specialist job? This customer has been riped off by 2 plumber so far and as she is 82 I think it is distgusting 
