Veissman 100 series combo boiler farts propane

Installed a Veissman 100 Series combi and noticing intermittent light smell of propane which appears to be coming from somewhere internal to the unit. Sprayed the external propane connections multiple times and have experienced tech scratching his head as to where the "fart" originates when it blows one out. I saw someone else reach out on the internet with a similar issue on this series boiler, however, the only response to the guy was for him to call the fuel provider and have it checked. Volume of propane that comes out of this boiler must be very low, otherwise the garage its in with apartment above would not be standing. Boiler ran all last winter in this condition. No excessive fuel usage noted. Perhaps something was missed in the startup procedure which leads to this condition. If so, I'd love to know what I need to do to rectify this intermittent smell of propane.