Struggling with my Worcester 18ri

[Sdemon]

Hi there

I recently had an issue with my Worcester 18ri boiler. It kept on trying to ignite and then after a while it would cut out. A plumber said that I had an unstable ignition and said that the gas valve is probably to blame.

The gas valve has been changed, the boiler serviced: cleaned, baffles, seals, electrodes. When the plumber changed the gas valve the boiler sounded like it was trying to get gas to flow when turned on and the green light would turn on for a moment and stop. This would happen 3-4 times and the boiler would cut out. The blue light would then go on then off for 3 seconds. He then did the min and max reset on the gas valve and the system worked all day.

Problem is now after the timer turned off the central heating, it’s doing that gas flow issue thing again but with no green light coming on at all. The boiler will then cut out and do that on and off for 3 seconds thing.

Really confused why this is happening and would appreciate and ideas.

Many thanks.

 

[Sdemon]

Update:

After adjusting the air gas flow in the valve it fires up.

My issue now is that it will randomly cut out at different stages. Sometimes before it ignites, at times when the central heating is fully operational. No fault codes just goes into system reset mode.

Any ideas?

 

[Sdemon]

Update:

Now the boiler will not activate at all. It tries to do a reset sequence then turns off. Blue light flashes more off than on and the. Eventually cuts out. The boiler is not kicking in at all

Any ideas would be helpful

Thanks