diff --git a/libecl/src/ecl_region.c b/libecl/src/ecl_region.c
index 2c3b06edc0..ca1a2faeb7 100644
--- a/libecl/src/ecl_region.c
+++ b/libecl/src/ecl_region.c
@@ -306,7 +306,7 @@ void ecl_region_deselect_cell( ecl_region_type * region , int i , int j , int k)
 static void ecl_region_select_equal__( ecl_region_type * region , const ecl_kw_type * ecl_kw, int value , bool select) {
   bool global_kw;
   ecl_region_assert_kw( region , ecl_kw , &global_kw);
-  if (ecl_type_is_int(ecl_kw_get_data_type( ecl_kw )))
+  if (!ecl_type_is_int(ecl_kw_get_data_type( ecl_kw )))
     util_abort("%s: sorry - select by equality is only supported for integer keywords \n",__func__);
   {
     const int * kw_data = ecl_kw_get_int_ptr( ecl_kw );
diff --git a/python/python/ert/ecl/ecl_region.py b/python/python/ert/ecl/ecl_region.py
index d340172a7f..c329f3bcff 100644
--- a/python/python/ert/ecl/ecl_region.py
+++ b/python/python/ert/ecl/ecl_region.py
@@ -417,6 +417,8 @@ def select_equal( self , ecl_kw , value , intersect = False):
            region.select_equal( pvtnum_kw , 4 )
 
         """
+        if not ecl_kw.data_type.is_int():
+            raise ValueError("The select_equal method must have an integer valued keyword - got:%s" % ecl_kw.typeName( ))
         self._select_equal( ecl_kw , value )
 
 
@@ -426,6 +428,8 @@ def deselect_equal( self , ecl_kw , value ):
 
         See select_equal() for further documentation.
         """
+        if not ecl_kw.data_type.is_int():
+            raise ValueError("The select_equal method must have an integer valued keyword - got:%s" % ecl_kw.typeName( ))
         self._deselect_equal( ecl_kw , value )
 
     @select_method
diff --git a/python/tests/core/ecl/CMakeLists.txt b/python/tests/core/ecl/CMakeLists.txt
index 2747cc0a96..e2cdb6551d 100644
--- a/python/tests/core/ecl/CMakeLists.txt
+++ b/python/tests/core/ecl/CMakeLists.txt
@@ -25,6 +25,7 @@ set(TEST_SOURCES
     test_kw_function.py
     test_layer.py
     test_npv.py
+    test_region.py
     test_region_statoil.py
     test_restart.py
     test_rft.py
@@ -62,6 +63,7 @@ addPythonTest(ecl.ecl_file ecl.test_ecl_file.EclFileTest)
 addPythonTest(ecl.ecl_grav ecl.test_grav.EclGravTest)
 addPythonTest(ecl.ecl_geertsma ecl.test_geertsma.GeertsmaTest)
 addPythonTest(ecl.ecl_type ecl.test_ecl_type.EclDataTypeTest)
+addPythonTest(ecl.ecl_region ecl.test_region.RegionTest)
 
 
 if (STATOIL_TESTDATA_ROOT)
diff --git a/python/tests/core/ecl/test_region.py b/python/tests/core/ecl/test_region.py
new file mode 100644
index 0000000000..921ef1457a
--- /dev/null
+++ b/python/tests/core/ecl/test_region.py
@@ -0,0 +1,37 @@
+#!/usr/bin/env python
+#  Copyright (C) 2017  Statoil ASA, Norway. 
+#   
+#  The file 'test_region.py' is part of ERT - Ensemble based Reservoir Tool.
+#   
+#  ERT is free software: you can redistribute it and/or modify 
+#  it under the terms of the GNU General Public License as published by 
+#  the Free Software Foundation, either version 3 of the License, or 
+#  (at your option) any later version. 
+#   
+#  ERT is distributed in the hope that it will be useful, but WITHOUT ANY 
+#  WARRANTY; without even the implied warranty of MERCHANTABILITY or 
+#  FITNESS FOR A PARTICULAR PURPOSE.   
+#   
+#  See the GNU General Public License at <http://www.gnu.org/licenses/gpl.html> 
+#  for more details.
+from ert.ecl import EclGrid, EclKW, EclRegion, EclDataType
+from ert.ecl.faults import Layer
+from ert.test import ExtendedTestCase
+
+
+class RegionTest(ExtendedTestCase):
+
+    def test_equal(self):
+        grid = EclGrid.createRectangular( (10,10,1) , (1,1,1))
+        kw_int = EclKW( "INT" , grid.getGlobalSize( ) , EclDataType.ECL_INT )
+        kw_float = EclKW( "FLOAT" , grid.getGlobalSize( ) , EclDataType.ECL_FLOAT )
+
+        kw_int[0:49] = 1
+        region = EclRegion(grid, False)
+        region.select_equal( kw_int , 1 )
+        glist = region.getGlobalList()
+        for g in glist:
+            self.assertEqual( kw_int[g] , 1 )
+
+        with self.assertRaises(ValueError):
+            region.select_equal( kw_float , 1 )