as i said its going to be signed off with gas safe and local council and with wb, i do have second thoughts about using this guy becuase of the price, but being approved by baxi & vallent i was thinking i cant go wrong here along with 000s positive reviews, im going to be taking a day off work (2nd day of fitting) which is i believe thats when the powerflush will be done, i will if i can post pictures on here of the installation and let you guys see the end result