diff --git a/src/domain.cpp b/src/domain.cpp
index b0a32ce114..1becba5e0b 100644
--- a/src/domain.cpp
+++ b/src/domain.cpp
@@ -1873,6 +1873,7 @@ void Domain::set_boundary(int narg, char **arg, int flag)
   else zperiodic = 0;
 
   // record if we changed a periodic boundary to a non-periodic one
+
   int pflag=0;
   if ((periodicity[0] && !xperiodic)
       || (periodicity[1] && !yperiodic)
@@ -1889,23 +1890,27 @@ void Domain::set_boundary(int narg, char **arg, int flag)
         boundary[1][0] >= 2 || boundary[1][1] >= 2 ||
         boundary[2][0] >= 2 || boundary[2][1] >= 2) nonperiodic = 2;
   }
+
+  // force non-zero image flags to zero for non-periodic dimensions
+  // keep track if a change was made, so we can print a warning message
+
   if (pflag) {
     pflag = 0;
     for (int i=0; i < atom->nlocal; ++i) {
       int xbox = (atom->image[i] & IMGMASK) - IMGMAX;
       int ybox = (atom->image[i] >> IMGBITS & IMGMASK) - IMGMAX;
       int zbox = (atom->image[i] >> IMG2BITS) - IMGMAX;
-      if (!xperiodic) { xbox = 0; pflag = 1; }
-      if (!yperiodic) { ybox = 0; pflag = 1; }
-      if (!zperiodic) { zbox = 0; pflag = 1; }
+      if ((!xperiodic) && (xbox != 0)) { xbox = 0; pflag = 1; }
+      if ((!yperiodic) && (ybox != 0)) { ybox = 0; pflag = 1; }
+      if ((!zperiodic) && (zbox != 0)) { zbox = 0; pflag = 1; }
       atom->image[i] = ((imageint) (xbox + IMGMAX) & IMGMASK) |
         (((imageint) (ybox + IMGMAX) & IMGMASK) << IMGBITS) |
         (((imageint) (zbox + IMGMAX) & IMGMASK) << IMG2BITS);
     }
     int flag_all;
-    MPI_Allreduce(&flag,&flag_all, 1, MPI_INT, MPI_SUM, world);
+    MPI_Allreduce(&pflag,&flag_all, 1, MPI_INT, MPI_SUM, world);
     if ((flag_all > 0) && (comm->me == 0))
-      error->warning(FLERR,"Reset image flags for non-periodic boundary");
+      error->warning(FLERR,"Resetting image flags for non-periodic dimensions");
   }
 }