diff --git a/avr/modules/heap/main.asm b/avr/modules/heap/main.asm
index 3dfb7c6..529a996 100644
--- a/avr/modules/heap/main.asm
+++ b/avr/modules/heap/main.asm
@@ -244,10 +244,10 @@ Heap_Free:
       st X+, r24                        ; write chunk footer
       st X+, r25                        ; X points to the next chunk header now
       rcall heapAdjustStatsFree         ; update stats (r16, r17)
-;      rcall heapCoalecseUp              ; try to coalecse following chunk with this (r16, r17, r24, r25, X)
+      rcall heapCoalecseUp              ; try to coalecse following chunk with this (r16, r17, r24, r25, X)
     pop xh
   pop xl
-;  rcall heapCoalecseUp                  ; try to coalesce this chunk with predecessor (r16, r17, r24, r25, X)
+  rcall heapCoalecseUp                  ; try to coalesce this chunk with predecessor (r16, r17, r24, r25, X)
   rjmp Heap_Free_ret
 Heap_Free_dblFree:
   lds r24, heapDblFree
@@ -361,6 +361,7 @@ heapUseChunk_split:
 heapUseChunk_directAlloc:
       ld r17, -X                          ; load allocated size from chunk header
       ld r16, -X
+      andi r16, 0xfc                      ; mask off lower two bits
       mov r18, r16
       sbr r18, (1<<HEAP_HEADER_BIT_USED)  
       st X, r18                           ; set USED bit in chunk header