Valiant EcoTech Not filling

[Lsmith]

My Valiant boiler has come up with the F22 fault a few times since it was installed which we have easily rectified.
Yesterday I noticed a radiator was leaking- we bled the radiator and there was quite a lot of air in it.
This morning the F22 fault happened so I went with my screwdriver to fill it up but nothing is happening this time- HELP!!!!
If any one has any suggestions it would be greatly appreciated

 

[gas4you]

Why are you trying to fill it using a screwdriver?

There are two grey plastic filling knobs under the boiler to open to fill it

 

[Lsmith]

Hmmm not on my boiler there isn't we were shown to turn the valve on the right hand side of the hose to fill it- just looked for some plastic knobs and there aren't any

 

[gas4you]

Is this the Ecotec pro then?

 

[Lsmith]

Yes sorry the Pro28

 

[gas4you]

Perhaps the non-return valve in the filling loop has jammed?