diff --git a/nuts_bolts.c b/nuts_bolts.c
index 614f3cd..0a8bf5c 100644
--- a/nuts_bolts.c
+++ b/nuts_bolts.c
@@ -9,10 +9,10 @@ int read_double(char *line, uint8_t *char_counter, double *double_ptr)
   
   *double_ptr = strtod(start, &end);
   if(end == start) { 
-    return(0); 
+    return(false); 
   };
 
   *char_counter = end - line;
-  return(1);
+  return(true);
 }
 
diff --git a/nuts_bolts.h b/nuts_bolts.h
index 7cd745d..bc0b892 100644
--- a/nuts_bolts.h
+++ b/nuts_bolts.h
@@ -33,6 +33,9 @@
 #define clear_vector(a) memset(a, 0, sizeof(a))
 #define max(a,b) (((a) > (b)) ? (a) : (b))
 
+// Read a floating point value from a string. Line points to the input buffer, char_counter 
+// is the indexer pointing to the current character of the line, while double_ptr is 
+// a pointer to the result variable. Returns true when it succeeds
 int read_double(char *line, uint8_t *char_counter, double *double_ptr);
 
 #endif
diff --git a/settings.c b/settings.c
index 1e6f290..ca1bc05 100644
--- a/settings.c
+++ b/settings.c
@@ -92,11 +92,15 @@ uint8_t settings_execute_line(char *line) {
   if(line[char_counter] == 0) { 
     settings_dump(); return(STATUS_OK); 
   }
-  read_double(line, &char_counter, &parameter);
+  if(!read_double(line, &char_counter, &parameter)) {
+    return(STATUS_BAD_NUMBER_FORMAT);
+  };
   if(line[char_counter++] != '=') { 
     return(STATUS_UNSUPPORTED_STATEMENT); 
   }
-  read_double(line, &char_counter, &value);
+  if(!read_double(line, &char_counter, &value)) {
+    return(STATUS_BAD_NUMBER_FORMAT);
+  }
   if(line[char_counter] != 0) { 
     return(STATUS_UNSUPPORTED_STATEMENT); 
   }