No boiler pressure?

[oliverwbarnes]

Hi, just after some advice before I call somebody out to have a look.
For the last few days the boiler (Ferroli Optima) has been working but all of the radiators only getting lukewarm (I don't think they need bleeding but might be wrong). Today I added a little water to the system thinking this might sort it (I put the pressure up to just under 2). The boiler will now not hold any pressure for longer than about half an hour. The central heating still works when the boiler has pressure as does the hot water (which is as hot as normal).

Anybody got any ideas? Thanks.

 

[bolshy]

You've either got a leak or a pressure problem and the PRV is lifting. What did the pressure rise to when the CH was on?

 

[oliverwbarnes]

Only slightly, about 0.2 bar maybe? AFAIK it's always just risen slightly but I've not really paid much attention to it until now so could be wrong.

 

[bolshy]

Well, the water is going somewhere. Are you sure you didn't overfill it and lift the PRV when you ran the CH? They quite often fail to re-seat again, unless they're new. I'd check the pressure relief pipe work outside, see if it's dribbling water.

 

[oliverwbarnes]

There's a little pipe outside behind the boiler which is dribbling. How do I sort that, presumably that's the problem?

 

[bolshy]

The pipe is connected to the PRV, you need a new valve. If you don't know what you're doing, don't attempt it. Get a heating engineer in, shouldn't cost much to repair.

 

[oliverwbarnes]

Right ok at least I know, thanks very much