diff --git a/_modules/runtest/tempest_sections/heat_plugin.py b/_modules/runtest/tempest_sections/heat_plugin.py
index da680cd..945ea39 100644
--- a/_modules/runtest/tempest_sections/heat_plugin.py
+++ b/_modules/runtest/tempest_sections/heat_plugin.py
@@ -165,11 +165,10 @@
             'nova.client.server.admin_identity.flavor', c)
         if not flavors:
             return
-        instance_type_name, _ = sorted(
-            flavors.items(),
-            key=lambda (k, v): (v, k)
-        )[-1]
-        return instance_type_name
+        flavor = [f for f in flavors if flavors[f]['disk'] > 3]
+        if not flavor:
+            return
+        return flavor[0]
 
     @property
     def ip_version_for_ssh(self):