diff --git a/src/MNH/read_dummy_gr_fieldn.f90 b/src/MNH/read_dummy_gr_fieldn.f90
index 314b6f31979dc3aa6773bba5f6e3e7f8eed149ec..2a65668c552456fe1c3478830064cd7740560502 100644
--- a/src/MNH/read_dummy_gr_fieldn.f90
+++ b/src/MNH/read_dummy_gr_fieldn.f90
@@ -200,14 +200,14 @@ IF (.NOT. ASSOCIATED(XDUMMY_GR_FIELDS)) &
 ALLOCATE(XDUMMY_GR_FIELDS(SIZE(XXHAT),SIZE(XYHAT),NDUMMY_GR_NBR))
 !
 DO JDUMMY=1,NDUMMY_GR_NBR
-  WRITE(YRECFM,'(A8,I3.3,A5)') 'DUMMY_GR',JDUMMY,'     '
+  WRITE(YRECFM,'(A8,I3.3)') 'DUMMY_GR',JDUMMY
   TZFIELD%CMNHNAME   = TRIM(YRECFM)
   TZFIELD%CSTDNAME   = ''
   TZFIELD%CLONGNAME  = 'MesoNH: '//TRIM(YRECFM)
   TZFIELD%CUNITS     = ''
   TZFIELD%CDIR       = 'XY'
   ! Expected comment is not known but is in the following form:
-  ! 'X_Y_'//YRECFM//YSTRING20//YSTRING03
+  ! 'X_Y_'//TRIM(YRECFM)//YSTRING20//YSTRING03
   TZFIELD%CCOMMENT   = ''
   TZFIELD%NGRID      = 4
   TZFIELD%NTYPE      = TYPEREAL
@@ -223,8 +223,8 @@ DO JDUMMY=1,NDUMMY_GR_NBR
   ENDIF
   XDUMMY_GR_FIELDS(:,:,JDUMMY) = ZWORK(IIINF:IISUP,IJINF:IJSUP)
   !
-  YSTRING20=TZFIELD%CCOMMENT( 4+LEN(YRECFM)+1                : 4+LEN(YRECFM)+LEN(YSTRING20) )
-  YSTRING03=TZFIELD%CCOMMENT( 4+LEN(YRECFM)+LEN(YSTRING20)+1 : 4+LEN(YRECFM)+LEN(YSTRING20)+LEN(YSTRING03) )
+  YSTRING20=TZFIELD%CCOMMENT( 4+LEN_TRIM(YRECFM)+1                : 4+LEN_TRIM(YRECFM)+LEN(YSTRING20) )
+  YSTRING03=TZFIELD%CCOMMENT( 4+LEN_TRIM(YRECFM)+LEN(YSTRING20)+1 : 4+LEN_TRIM(YRECFM)+LEN(YSTRING20)+LEN(YSTRING03) )
   !
   CDUMMY_GR_NAME(JDUMMY) = YSTRING20
   CDUMMY_GR_AREA(JDUMMY) = YSTRING03
diff --git a/src/MNH/write_dummy_gr_fieldn.f90 b/src/MNH/write_dummy_gr_fieldn.f90
index a4e06fee0502925900ca01df2c27a8843ccc5972..8c87543aa80291af1704dae06f2686fb181fe088 100644
--- a/src/MNH/write_dummy_gr_fieldn.f90
+++ b/src/MNH/write_dummy_gr_fieldn.f90
@@ -120,7 +120,7 @@ TZFIELD%NDIMS      = 0
 CALL IO_WRITE_FIELD(TPFILE,TZFIELD,NDUMMY_GR_NBR)
 !
 DO JDUMMY=1,NDUMMY_GR_NBR
-  WRITE(YRECFM,'(A8,I3.3,A5)') 'DUMMY_GR',JDUMMY,'     '
+  WRITE(YRECFM,'(A8,I3.3)') 'DUMMY_GR',JDUMMY
   YSTRING20=CDUMMY_GR_NAME(JDUMMY)
   YSTRING03=CDUMMY_GR_AREA(JDUMMY)
   !