Philippe 25/02/2019: bug correction for the file unit numbers

src/MNH/ch_init_constn.f90

-!MNH_LIC Copyright 1994-2018 CNRS, Meteo-France and Universite Paul Sabatier
+!MNH_LIC Copyright 2001-2019 CNRS, Meteo-France and Universite Paul Sabatier
 !MNH_LIC This is part of the Meso-NH software governed by the CeCILL-C licence
-!MNH_LIC version 1. See LICENSE, CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt  
+!MNH_LIC version 1. See LICENSE, CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt
 !MNH_LIC for details. version 1.
 !-----------------------------------------------------------------
 !!    ################################ 
@@ -56,8 +56,8 @@ END MODULE MODI_CH_INIT_CONST_n
 !!    MODIFICATIONS
 !!    -------------
 !!    Original 16/02/01
-!!  Philippe Wautelet: 05/2016-04/2018: new data structures and calls for I/O
-
+!  P. Wautelet: 05/2016-04/2018: new data structures and calls for I/O
+!  P. Wautelet: 25/02/2019: bug correction for the file unit numbers
 !!    EXTERNAL
 !!    --------
 USE MODI_CH_OPEN_INPUT  ! open the general purpose ASCII input file
@@ -241,6 +241,7 @@ IF (KVERB >= 5) WRITE(KLUOUT,*) &
    "CH_INIT_CONST: reading effective Henry constant", &
    " and its temperature correction "
 CALL CH_OPEN_INPUT(CCHEM_INPUT_FILE, "HENRY_SP", TZFILE, KLUOUT, KVERB)
+ICHANNEL = TZFILE%NLU
 !
 ! read number of molecular diffusivity IHENRY
 READ(ICHANNEL, *) IHENRY