Herz pellet boiler problem with engine failure

[Zelda]

Hello, thank you for accepting it on the forum, we had a Herz pellet boiler installed in December 2016, it was serviced every year and this year in June the technician said it was making a weird noise, but didn't know what it was . We have just restarted it, the engine has broken down, it is he who is making a rattling noise. Can you tell me who should take care of dispatch? The installer, the company that has done the maintenance so far, where is this our responsibility? We don't even know the cause of this problem. thanks for your advices