diff --git a/src/cmfd_execute.F90 b/src/cmfd_execute.F90
index 04b767855d..f3a0959bdb 100644
--- a/src/cmfd_execute.F90
+++ b/src/cmfd_execute.F90
@@ -52,7 +52,7 @@ contains
     write(108,*) cmfd % dhat
 
     ! write cmfd object to hdf5 file
-!   call write_hdf5()
+    call write_hdf5()
 
     ! solve diffusion equation
     call cmfd_solver()
@@ -668,7 +668,7 @@ use timing, only: timer_start, timer_stop
 
     ! calculate dimensions of matrix
     if (allocated(cmfd % coremap)) then
-      n = cmfd % mat_dim
+      n = cmfd % mat_dim * ng
     else
       n = nx*ny*nz*ng
     end if
diff --git a/src/cmfd_utils.F90 b/src/cmfd_utils.F90
index 370bc62bff..f40b944c21 100644
--- a/src/cmfd_utils.F90
+++ b/src/cmfd_utils.F90
@@ -134,7 +134,7 @@ contains
 
       ! get idx from core map
       nidx = ng*(cmfd % coremap(i,j,k)) - (ng - g)
-
+      write(200,*) g,i,j,k,nidx
     else
 
       ! compute index