diff --git a/opm/simulators/wells/MultisegmentWell_impl.hpp b/opm/simulators/wells/MultisegmentWell_impl.hpp
index 7f8ff9146..2b8f7a07e 100644
--- a/opm/simulators/wells/MultisegmentWell_impl.hpp
+++ b/opm/simulators/wells/MultisegmentWell_impl.hpp
@@ -814,8 +814,18 @@ namespace Opm
                     diag_ell -= matel;
                 }
             }
-        
-            assert(diag_ell > 0.0);
+
+#define EXTRA_DEBUG_MSW 0
+#if EXTRA_DEBUG_MSW            
+            if(not(diag_ell > 0.0)){
+                std::stringstream msg;
+                msg << "Diagonal element for cprw on "
+                          << this->name()
+                          << " is " << diag_ell;
+                OpmLog::warning(msg.str());
+            }
+#endif
+#undef EXTRA_DEBUG_MSW            
             jacobian[welldof_ind][welldof_ind] = diag_ell;
         }else{
             jacobian[welldof_ind][welldof_ind] = 1.0; // maybe we could have used diag_ell if calculated
@@ -1579,6 +1589,7 @@ namespace Opm
                 sstr << " " << measure_history[i] << " \n";
             }
 #endif
+#undef EXTRA_DEBUG_MSW
             deferred_logger.debug(sstr.str());
         }