humming noise/pressure in combi boiler

Hi

For several weeks we've had a badly leaking bath faucet that it seems has caused some humming in our pipes. (The landlord if finally coming tomorrow to fix it.) I took a look at the pressure in the combi boiler (Biasi) and noticed that it was nearly 0 and wondered if this might be a cause of the humming or merely another symptom of the leak (?). I decided to use the filler loop to increase the pressure and didn't realize it would increase so fast! The pressure is now at 2.5, which I gather is too high. But I'm wondering how big a problem this is and what I should do. I don't know where the pressure relief valve is, and I vaguely recall someone advising not to use it, since they often leak. Anyone with any tips?

thanks

RH

Sorry I missed this earlier, Ron.

Low pressure could indeed cause a noise from the boiler, not such much from the pipes tho'.  A leak on your taps will not cause the system pressure on your boiler to drop.

It's ok to top up your pressure, but I wouldn't go above 1.5 bar.  If you top up 3 bar or more you will cause the pressure relief valve (PRV) to blow off which can bring problems of its own.  Always make sure you have securely closed the filling loop.  If it does not close properly, water will continuously fill the system and cause the PRV to blow off.

2.5 bar is a bit high, but you can try to release some of the pressure by bleeding your rads, but do keep an eye on the pressure as you do it so that you don't drop down below 1 bar.

Having to regularly top up the system is indication that there's a problem somewhere ... most likely a leak.  This often happens on rads but can be difficult to find; as the rads heat up the moisture evaporates.

If you are refilling the system with fresh water, chances are your system inhibitor levels have become low and may need replacing.

Thanks, Mrs C. As it happened, the landlord came and sorted out the noise in the water pipes and the problem with the boiler pressure.