boiler making small explosion nosie when firing up

[browfish]

I installed an Ariston ACO 32 system boiler just over a year ago. I installed all teh plumbing around the house myself and my plumber connected the boiler up. It has works fine for the last year however very occasionally makes a noise like a small gas explosion, a whuump noise! Enough to make me jump in the adjacent room. It only does it when kicking into action and only every so often.

My plumber came out to have a look about 6 months ago but couldnt see anything wrong and it worked fine when he was there on numerous tests. The reason i ask now is that it did it againt this morning.

Any ideas on what the problem could be?
thanks

 

[gigz]

Sounds like explosive ignition, time to get an engineer in.

 

[spacethegas]

explosive ignition.

you need qualified boilerman.

 

[spacethegas]

SNAP

 

[browfish]

Thanks for that
Do you know what he should be looking out for and possible problems so that i dont get anyone try and rip me off?