Broken boiler
Broken boilers sometimes appear in the Lava Flow Mine as a distraction due to chaos dwarf attacks. To fix it, players must have a hammer (there is a spawn at the entrance of the mine) and the appropriate Smithing level (varies depending on the boiler). Boilers may only be fixed once per hour. The Assist System CANNOT be used to fix a boiler.
The calculator below will show you how much Smithing experience you will get based on the level required to fix the boiler (not the player's Smithing level):