Hi I am looking for some advise on this water heater please. The blend valve is leaking (90000010) is it just a case of isolating cold mains and opening taps hot/cold to drain of water to be able to change this part without having a bath ?. I have Got part on order for next week ,is there any potential problems that I may encounter or is it just as easy as it looks?.:rolleyes2: many thanks mark.