Help with Valliant Error Code F28

[sushil]

Can any one help me understand what Error code F28 means on my valliant Combi Boiler, The boiler is about 5 years old.
The book states it is lock out.
How do I go about resetting it or is there a major problem.

 

[micky p]

ive just checked in the manual and it has failed to light by the sounds of things. Is the gas turned on( iknow it sounds silly but may not be on if a card meter) Other than that could be a few things like gas valve etc.

 

[bobw1956]

F28 Boiler goes to lockout.

No Gas

Insufficient gas

Incorrect gas valve adjustment
Electrode defective
Ignition lead defective
Electronic igniter defective

Try reseting by pressing the reset button on the front of the boiler