diff --git a/istl/solvers.hh b/istl/solvers.hh
index 4b897f173189424e57ee976c77301354f38fc177..7aa3a8be9b765caba8b0e6ed3092b85388d9a080 100644
--- a/istl/solvers.hh
+++ b/istl/solvers.hh
@@ -480,7 +480,7 @@ namespace Dune {
     //! apply inverse operator
     virtual void apply (X& x, X& b, InverseOperatorResult& res)
     {
-      const double EPSILON=1e-20;
+      const double EPSILON=1e-40;
 
       int it;
       field_type rho, rho_new, alpha, beta, h, omega;