ok thanks for that.
say on a pumped ch gravity dhw, im wondering of best ways to isolate dhw,
also do you isolate cold feed and cap vent or prefer to remove f&e tank and join pipes together as suggested in training?
when connecting to a system where theyre keeping old boiler for instance mexico or classic do you run through boiler or take boiler out of equation
the way i was tought to do it was to begin flush with all rads open add chems change direction frequently isolate all rads except 1 flush that for a while (how long do you do it for?) then open another and close that then when you get to the end start dumping 1 by 1 until theyre all clean as a whistle
sorry for the essay