i had to take off 2 radiators a while ago and ive just re-connected them, i tightened the nuts, and opened the valves, then i bled them...
as i bled them the pressure decreased so i shut the vent and when to fill the system. the boiler was flashing 0.0 bar. i got my key and opened the filler but no water is coming in to fill the system up...
what do i have to do to fill up the system??