diff --git a/src/netcdf/netcdf.f90 b/src/netcdf/netcdf.f90
index c36408a72..60e17fa0c 100644
--- a/src/netcdf/netcdf.f90
+++ b/src/netcdf/netcdf.f90
@@ -767,21 +767,36 @@ module subroutine netcdf_read_hdr_system(self, iu, param)
       end select
 
       if (param%lenergy) then
-         call check( nf90_get_var(iu%ncid, iu%KE_orb_varid,      self%ke_orbit,    start=[tslot]), "netcdf_read_hdr_system nf90_getvar KE_orb_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%KE_spin_varid,     self%ke_spin,     start=[tslot]), "netcdf_read_hdr_system nf90_getvar KE_spin_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%PE_varid,          self%pe,          start=[tslot]), "netcdf_read_hdr_system nf90_getvar PE_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_orbx_varid,      self%Lorbit(1),   start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_orbx_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_orby_varid,      self%Lorbit(2),   start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_orby_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_orbz_varid,      self%Lorbit(3),   start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_orbz_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_spinx_varid,     self%Lspin(1),    start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_spinx_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_spiny_varid,     self%Lspin(2),    start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_spiny_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_spinz_varid,     self%Lspin(3),    start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_spinz_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_escapex_varid,   self%Lescape(1),  start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_escapex_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_escapey_varid,   self%Lescape(2),  start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_escapey_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%L_escapez_varid,   self%Lescape(3),  start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_escapez_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%Ecollisions_varid, self%Ecollisions, start=[tslot]), "netcdf_read_hdr_system nf90_getvar Ecollisions_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%Euntracked_varid,  self%Euntracked,  start=[tslot]), "netcdf_read_hdr_system nf90_getvar Euntracked_varid"  )
-         call check( nf90_get_var(iu%ncid, iu%GMescape_varid,    self%GMescape,    start=[tslot]), "netcdf_read_hdr_system nf90_getvar GMescape_varid"  )
+         status = nf90_inq_varid(iu%ncid, KE_ORB_VARNAME, iu%KE_orb_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%KE_orb_varid,      self%ke_orbit,    start=[tslot]), "netcdf_read_hdr_system nf90_getvar KE_orb_varid"  )
+         status = nf90_inq_varid(iu%ncid, KE_SPIN_VARNAME, iu%KE_spin_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%KE_spin_varid,     self%ke_spin,     start=[tslot]), "netcdf_read_hdr_system nf90_getvar KE_spin_varid"  )
+         status = nf90_inq_varid(iu%ncid, PE_VARNAME, iu%PE_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%PE_varid,          self%pe,          start=[tslot]), "netcdf_read_hdr_system nf90_getvar PE_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_ORBX_VARNAME, iu%L_orbx_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_orbx_varid,      self%Lorbit(1),   start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_orbx_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_ORBY_VARNAME, iu%L_orby_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_orby_varid,      self%Lorbit(2),   start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_orby_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_ORBZ_VARNAME, iu%L_orbz_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_orbz_varid,      self%Lorbit(3),   start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_orbz_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_SPINX_VARNAME, iu%L_spinx_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_spinx_varid,     self%Lspin(1),    start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_spinx_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_SPINY_VARNAME, iu%L_spiny_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_spiny_varid,     self%Lspin(2),    start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_spiny_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_SPINZ_VARNAME, iu%L_spinz_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_spinz_varid,     self%Lspin(3),    start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_spinz_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_ESCAPEX_VARNAME, iu%L_escapex_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_escapex_varid,   self%Lescape(1),  start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_escapex_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_ESCAPEY_VARNAME, iu%L_escapey_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_escapey_varid,   self%Lescape(2),  start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_escapey_varid"  )
+         status = nf90_inq_varid(iu%ncid, L_ESCAPEZ_VARNAME, iu%L_escapez_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%L_escapez_varid,   self%Lescape(3),  start=[tslot]), "netcdf_read_hdr_system nf90_getvar L_escapez_varid"  )
+         status = nf90_inq_varid(iu%ncid, ECOLLISIONS_VARNAME, iu%Ecollisions_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%Ecollisions_varid, self%Ecollisions, start=[tslot]), "netcdf_read_hdr_system nf90_getvar Ecollisions_varid"  )
+         status = nf90_inq_varid(iu%ncid, EUNTRACKED_VARNAME, iu%Euntracked_varid)
+         if (status == nf90_noerr) call check( nf90_get_var(iu%ncid, iu%Euntracked_varid,  self%Euntracked,  start=[tslot]), "netcdf_read_hdr_system nf90_getvar Euntracked_varid"  )
+         status = nf90_inq_varid(iu%ncid, GMESCAPE_VARNAME, iu%GMescape_varid)
+         if (status == nf90_noerr)  call check( nf90_get_var(iu%ncid, iu%GMescape_varid,    self%GMescape,    start=[tslot]), "netcdf_read_hdr_system nf90_getvar GMescape_varid"  )
       end if
 
       return