Ferroli boiler strange ignition problems

[simonrossi]

Had a FER Falcon boiler for 3 years with no problems at all.
Had it serviced last week and since then it manifests a bizarre problem.
Hot water ignition no problem starts fine every time.
The heating also works fine except every so often, when lighting for the heating system, it makes a much louder noise than the normal "Woof" sound it makes when lighting, however it obviously does not light, as then tries again same large sound, and fails. And on the third attempt tries again and always lights normally. It always lights on the third attempt when it never makes the loud noise.
The louder "woof" sound I describes sounds like when you leave the gas ring on a bit too long berfore lighting, and since a larger amount of gas is lighting you get a louder noise. Hope this makes sense!
I know i'll have to get my corgi plumber back out but does anyone have any idea of what this might be. As I say the heating and water work fine.Its just these 2 noisy attempts at ignition that are odd, especially when the boiler has only just been serviced. I know I need to get my cori man back but can anyone tell me what might cause this problem

Thanks
Simon Rossi

 

[yachty]

I have the same fault, what was your diagnosis and remedy.

much appreciated

 

[kevindgas]

OP has probably died of boredom after 6 years!!

problem though is possibly the low flame setting an RGI will know what to do.