diff --git a/oven.py b/oven.py
index 6e17762..c0dd022 100644
--- a/oven.py
+++ b/oven.py
@@ -13,6 +13,7 @@ class Oven (threading.Thread):
 
     def __init__(self):
         threading.Thread.__init__(self)
+        self.daemon = True
         self.profile = None
         self.start_time = 0
         self.power = 0.0
@@ -67,6 +68,8 @@ class TempSensor(threading.Thread):
     
     def __init__(self,oven):
         threading.Thread.__init__(self)
+        self.daemon = True
+        
         self.temperature = 0
         self.oven = oven
         
diff --git a/picoreflowd.py b/picoreflowd.py
index 84f950a..72d8974 100644
--- a/picoreflowd.py
+++ b/picoreflowd.py
@@ -28,6 +28,8 @@ def notifyAll(message):
 class OvenWatcher(threading.Thread):
     def __init__(self,oven):
         threading.Thread.__init__(self)
+        self.daemon = True
+        
         self.oven = oven
 
     def run(self):