Topping up Boiler

[towser]

Hi - I have what is probably a basic question.

I have what I think is called a system boiler - essentially one that feeds a a hot water tank in the airing cupboard, it also drives the central heating. Worked fine for the last couple of years - radiators had a few cold spots so I bled them and then went to top up the boiler.

Pressure guage is at the bottom but boiler (Worcester Bosch Greenstar 24i) will still fire and provide hot water.

Located the filling loop under the sink and turn it on - sounds like water entering the boiler, let it run for a minute but guage has hardly moved up - but it has increased very slightly.

Let it run longer guage barely moved and it doesn't sound like water is entering the boiler anymore from the filling loop.

Any advice most welcome!

[ARHarh]

Unless you have a massive system, or bled pints of water out of the rads it should fill back up reasonably quickly, probably 30 seconds or so.

Is it the sort with a filling key?
is there a tap at both ends of the filling loop.
You have done the radiator bleed keys back up tight?

[towser]

Problem solved - I traced the cold water pipework and found that there was a fill loop on the cold water pipe beside the hot water tank in the airing cupboard.

Turned that on and the boiler topped up. Bit random as it's the other side of the house from the boiler itself. So managed to get it up to 1.5 bar in 30 seconds.

I've no idea what the other loop does, maybe it was for an old boiler.