To provide a fire extinguisher capable of effectively scattering fire extinguishing liquid to a fire generating position even when a heat exchanging rotary element cannot rotate due to the fire upon generation of the fire of the heat exchanging rotary element of a regenerative air pre-heater.

On the upper surface of the heat exchanging rotary element 7, a substantially rod type movable fire extinguishing nozzles 11 formed by arranging a plurality of fire extinguishing liquid scattering openings 12 is disposed. The fire extinguishing nozzle 11 can rotate about the same rotation axis as that of the heat exchanging rotary element 7 on the upper surface of the heat exchanging rotary element 7 by a motor 13, gears 15 and 16 and a manually rotating handle 14. The fire extinguishing nozzle 11 is moved to the fire generating position to scatter the fire extinguishing liquid.