The customer stated black soot from the boiler. Pulled the flu pipe off the boiler and found it Sooted. Found the breach of the boiler top completely rusted and rotted out. We are not able to get the part right now and it is unsafe to clean the boiler and run it this way. We will need to get the part tomorrow and return to clean it and install the part if we are able to get it then. The boiler may not be Sooted due to this breech and it may be another issue which we will need to figure out when we clean it. Spoke with the landlord, he said this should have been addressed with the cleaning even though during the cleaning the breech was not this bad. Water had leaked into the flu pipe due to the gutters being clogged and it went through the power venter and into the boiler. The customer did nit agree to repairs or pay the diagnostic, he wants to speak with a manager.