Troubleshooting: Sand Not Smelting in the Blast Furnace

Check the Basics First

If sand sits in the blast furnace without converting, confirm three things: the mod is actually loaded (check your mods list), the sand is in the top input slot and not the fuel slot, and you have valid fuel in the bottom slot. A blast furnace with no fuel will not process anything, even valid recipes.

Verify the Config

Open the mod's config screen or the blastingsand.json file in your profile folder. Confirm that sand is still listed as a valid input and that glass is its output. If you or another modpack author edited the file, an accidental deletion or typo could have removed sand from the list. Restore the sand entry and save.

Mod Conflicts and Recipe Overrides

Other mods can override or remove blast furnace recipes. If you recently added a mod that changes smelting behavior, it may be intercepting sand before this mod can process it. Try removing recently added mods one at a time to isolate the conflict. Also make sure you are using actual sand and not a modded sand variant that has a different registry name — only the exact block registered in the config will smelt. If all else fails, delete the config file so the mod regenerates it with defaults on next launch.