Flue

[David Banks]

Flue only goes too roof line then stops. Only brick from roof up. Oil fired boiler.
Would this not cool the gases before exiting the chimney?

[Eric Barker]

Dave,

Technically, the flue goes to the top of the chimney - the liner stops at the roof line. The flue is actually the space inside the chimney, it's not a component of the chimney (or a vent).

It warrants correction by a certified sweep.

[Nick Ostrowski]

I think the flue interior of the chimney could only be called lined if the chimney were constructed with two thicknesses of bricks. Then the inside layer is the liner. If it is single brick thickness for Dave's scenario, you only have a liner in half the chimney. Even if no spalling or deterioration were present, I would recommend a liner in the full length of the chimney interior.

[Jerry Peck]

David's photo shows an unlined chimney.

Probably needs a SS liner installed.

[Robert Dalga]

Yes, the photo shows an unlined chimney and Yes, flue gases could possibly condense accelerating the decomp of the bricks and mortar. You didn't say how old the furnace was (I'll assume not new), but if a new furnace was to ever be installed it would/should have a flue liner installed with it.

[David Banks]

Yes, the photo shows an unlined chimney and Yes, flue gases could possibly condense accelerating the decomp of the bricks and mortar. You didn't say how old the furnace was (I'll assume not new), but if a new furnace was to ever be installed it would/should have a flue liner installed with it.


Thanks Robert. 1990 Boiler.