diff --git a/inventoryManager.lua b/inventoryManager.lua
index f765ae7..766a10e 100644
--- a/inventoryManager.lua
+++ b/inventoryManager.lua
@@ -772,7 +772,37 @@ local function autoSmelt()
             -- Re-read after output pull
             contents = furnace.list()
 
-            -- 2) Refuel if fuel slot is empty or low
+            -- 2) Check for incompatible items in input slot and remove them
+            local furnaceType = peripheral.getType(fname)
+            local inputItem = contents[SLOT_INPUT]
+            if inputItem then
+                local recipe = SMELTABLE[inputItem.name]
+                local validHere = false
+                if recipe then
+                    for _, ft in ipairs(recipe.furnaces) do
+                        if ft == furnaceType then
+                            validHere = true
+                            break
+                        end
+                    end
+                end
+                if not validHere then
+                    -- This item doesn't belong in this furnace type — pull it out
+                    for _, chest in ipairs(chests) do
+                        local n = furnace.pushItems(chest, SLOT_INPUT)
+                        if n and n > 0 then
+                            print(string.format("[SMELT] Removed incompatible %s x%d from %s -> %s",
+                                inputItem.name, n, fname, chest))
+                            didWork = true
+                            break
+                        end
+                    end
+                    -- Re-read after removal
+                    contents = furnace.list()
+                end
+            end
+
+            -- 3) Refuel if fuel slot is empty or low
             local fuelItem = contents[SLOT_FUEL]
             local needFuel = not fuelItem or fuelItem.count < 8
 
@@ -803,9 +833,8 @@ local function autoSmelt()
                 end
             end
 
-            -- 3) Load smeltable items into empty input slot
-            local inputItem = contents[SLOT_INPUT]
-            local furnaceType = peripheral.getType(fname)
+            -- 4) Load smeltable items into empty input slot
+            inputItem = contents[SLOT_INPUT]
             if not inputItem then
                 -- Find something smeltable in chests that this furnace type can process
                 for itemName, recipe in pairs(SMELTABLE) do