Hi, I'm trying to research requirements for a heavy fuel oil boiler regarding safe maintenance and inspection. 2 older fuel oil boilers (infrequently used) have been recently returned to service at our site to alow for maintenance of a new gas boiler. When returned to service it was reported there was a lot of soot ejected into the local internal area of the boiler house. Would anyone be able to help me with regards why there would be soot ejected and if this would indicate any problems with the system? Also, what required inspections are required for this type of equipment? cheer