Is it time for a cleaning?
Now that we’re in the dead of winter, if you haven’t had your boiler serviced you really should. The burning of fuel creates exhaust and this exhaust contains soot that can adhere to the insides of the boiler exhaust tubes. As the build-up of soot continues it begins to restrict the ability of the boiler to vent the exhaust up and out to the chimney. The exhaust has to go somewhere and typically it vents into the basement through the chamber door. This allows carbon monoxide (CO2) into the home. In the photo to the right just under the silver oval combustion chamber door, the black soot that you see is exhaust that has escaped from the boiler and into the home. If the front of your boiler looks like the boiler above, it is need of cleaning and servicing to avoid allowing CO2 into the home.
When the back drafting is severe enough to the point where the boiler is almost completely clogged, flames will actually be visible from the chamber door. This is visible in the photo to the left. You don’t have to be a home inspector to see that the  situation is not healthy.
These are actual photos that were taken during home inspections. Our advice, of course, was to have a licensed heating contractor immediate view and service the heating system.
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