Boiler dropping pressure

Hello all,


Just moved into a new house and was met with a nasty surprise. The boiler (Ferroli DOMICOMPACT F30D or F24D) is losing pressure within a span of 4 hours or so. It goes from 2.0bar down to 0.8 - 1.0 bar. The boiler itself appears to be working fine and heats the house up withouth a problem when pressurised.

I suspect a faulty PRV as the pipe outside that connects boilers manual release (to release pressure from the boiler) and inner part within the boiler (I suspect the PRV) always appears to be dripping water when the boiler is pressurised.

Not sure if I should attempt the fix myself or get someone? What would a PRV replacement cost?


Thank you.

It shouldn't be at 2.0 bar in the first place. 1.2-1.5 is sufficient. The PRV will probably need changing but look at the expansion vessel as that is the most likely culprit. Ferroli parts tend to be quite expensive unfortunately

Yeah it appears that the expansion vessel is shot too but the boiler is 18 years old and thus was advised not to repair but replace.
What they are going to install is Main eco compact 30 for £1300