L2 error on Ideal Boiler

[Yanni]

My gas fitter repaired a leak on a radiator pipe.
Then the boiler started making very deep bassy noises and starting giving an F2 error.
I've asked him about the error and he said he doesn't know what it is maybe the wind.

I restarted the boiler a few times and then the F2 error disappeared and worked ok for a day.
This morning the tenant moved in and the boiler now gives an L2 error.

Any ideas? Very new boiler and British Gas has tested it and passed everything before.
I have cover with British Gas but the earliest appointment they give me is in 12 days!
My gas fitter said when he fixed the radiator he did not touch the gas.

Any ideas?

 

[ianmcd]

L2 means loss of flame , so check gas is turned on at the meter and it has credit if pre-pay and is actually on, anything else you cant sort yourself

 

[CBW]

F2 seems related to flame loss too, so could have been the gas running out on a prepayment meter as Ian suggests.

 

[kidgreen61]

My money is on partially blocked condi pipe

 

[Yanni]

Thanks guys, I watched a youtube video and fixed it. It was the siphon above the condensate pipe that was full with black sud.
I cleaned it as in this video:

and run the boiler, left it overnight, then switched it back on and voila!
All works fine.