Help! Gloworm 24cxi boiler not refilling pressure

[sgle230678]

Our boiler is 3 yrs old and never had any problems with it in past. When it has needed pressure topping up we have used the filling loop fine.
Today we took a radiator off to decorate and the pressure in boiler automatically dropped to 0.0 bar (digital display) and red warning light.So we switched boiler off.
Have now connected rad back up and cant fill the boiler back up. We have bled all the radiators, and the filling loop is definately turning but can not hear any water going in and display is still reading 0.0 bar.
As a result (we assume) have no hot water or heating.
Can not see any other thing thats obvious to fill it with, despite reading manual. Will this require a costly call out from a plumber, or are we missing somthing

 

[Rob]

If its the built in filling loop with the blue knob then theyre known for being troublesome.

Get a plumber round to install a new one underneath the boiler. Very reliable!

 

[sgle230678]

Yeah thats the one, worked fine before though but today its just turning and nothing happening!

 

[uknokianut]

Had to change one of these just last week, exactly the same problem . Very easy to fit though.