Brick fallen down chimney

[harbinger]

What should I do?

Our wood stove has a liner, so probably not down that one. Or is it? Have not dared light the fire today.
Two more are unused (bedroom) and the other has a gas fire in the room.

at a guess, it probably fell from the top. In which case the mortar at the top is perished, with many years exposure to weather and acid fumes. If so, then the top of the stack needs rebuilding, which will mean scaffolding, bricklaying and reflashing with lead. Properly done with modern cement it will last 50 years or maybe 100.

On the other hand it might be something less expensive.

Have a look with binoculars and start asking round for recommendations for a local builder. Your chimneysweep will probably know someone reliable, or may do chimney repairs himself, or at least take a look and advise.

Chimney sweep was round on Tuesday (weep) and very busy.
I've a feeling, from what I heard (tumble,tumble,thump) that it was probably the upstairs fireplace. Front or back, I don't know. Will light fire tomorrow...... will soon know if it's that chimney!