diff --git a/frappy_psi/dilhtr.py b/frappy_psi/dilhtr.py
index 4fd97a71..3c172be4 100644
--- a/frappy_psi/dilhtr.py
+++ b/frappy_psi/dilhtr.py
@@ -20,6 +20,7 @@
 from frappy.core import StringIO, HasIO, Writable, Parameter, FloatRange, IntRange, \
     IDLE, ERROR
 from frappy.errors import CommunicationFailedError
+from frappy.ctrlby import WrapControlledBy
 
 
 class IO(StringIO):
@@ -72,3 +73,7 @@ class Heater(HasIO, Writable):
         if reply != 'h':
             raise CommunicationFailedError(f'bad reply from status request: {reply}')
         return self.status_map.get(status, (ERROR, 'bad status'))
+
+
+class WrappedHeater(WrapControlledBy, Heater):
+    pass
diff --git a/frappy_psi/tcs.py b/frappy_psi/tcs.py
index e103f360..e27664c3 100644
--- a/frappy_psi/tcs.py
+++ b/frappy_psi/tcs.py
@@ -26,7 +26,6 @@ from frappy.ctrlby import WrapControlledBy
 class IO(StringIO):
     end_of_line = '\n'
     identification = [('ID?', '0\t.*')]  # senden: ID?<lf>, Antwort: 0<ht> str version information<lf>
-    #default_settings = {}
 
 
 class Heater(HasIO, Writable):