diff --git a/watpy/utils/coreh5.py b/watpy/utils/coreh5.py
index 459142f282fb92c05406a01f286915967b8b6cbe..f2e1ea05d110333e49476f2e369d123853daed37 100644
--- a/watpy/utils/coreh5.py
+++ b/watpy/utils/coreh5.py
@@ -49,7 +49,7 @@ class CoRe_h5():
         - Dasets are named after filenames
         - Appends to and/or overwrites HDF5
         """
-        if path is None: path == self.path
+        if path is None: path = self.path
         if not dfile:
             self.dfile = 'data.h5'
         else: