FERROLI PROBS?

not sure if am in the rite place here... hv a question for the plumbers... i also have a nuisance ferroli... pressure reading at 3 bit despite bleeding loads of water from radiator it refills itself... overflow constantly dripping water... where abouts can i attach a bike pump to? (no rude replies plz!) is there any danger in doing this? hv kids to think about... if i cant fix this myself plz can u advise me of what would be a reasonable price to fix this problem... yr response would be much appreciated!