We have had a woodburner for about 4 years now, but in the last few days we have had a problem with smoke coming back from the burner.
The flue was swept at the end of October and the fire has been in daily use since. We burn compressed rape seed husks that have given us no problems in the past.
There is a vent at the top (to keep the glass clear), two dampers at the bottom front of the fire and a flue damper.
Generally we start with all dampers open, when it is going well we shut the bottom dampers and can control it on the flue damper. The top vent always stays open.
BUT, in the last few days whenever we start the fire, or in fact at any time that it is lit, if the bottom dampers are opened, copious quantities of smoke come out the top vents. This means that to have the fire on (and to breathe!) we need to have all the dampers shut, which leads to a "sulky" fire, not a lot of heat and as this is also the back boiler for the radiators, a cold house.
I have looked inside the fire and there is nothing obvious blocking anywhere (including the flue damper).
We originally thought it may be to do with the weather, high pressure and very still, but I am now wondering if we have a partial blockage of the flue (there is some smoke coming out of the top of the chimney).
Before I call a sweep out, is there anything obvious that I have missed?
Cheers
Peter
Train set at