diff --git a/cara/apps/expert.py b/cara/apps/expert.py
index c6ee010e..e553aac4 100644
--- a/cara/apps/expert.py
+++ b/cara/apps/expert.py
@@ -288,8 +288,9 @@ baseline_model = models.Model(
     room=models.Room(volume=75),
     ventilation=models.WindowOpening(
         active=models.PeriodicInterval(period=120, duration=120),
-        inside_temp=293, outside_temp=283, cd_b=0.6,
-        window_height=1.6, opening_length=0.6,
+        inside_temp=models.PiecewiseconstantFunction((0,24),(293,)),
+        outside_temp=models.PiecewiseconstantFunction((0,24),(283,)),
+        cd_b=0.6, window_height=1.6, opening_length=0.6,
     ),
     infected=models.InfectedPerson(
         virus=models.Virus.types['SARS_CoV_2'],
diff --git a/cara/tests/test_known_quantities.py b/cara/tests/test_known_quantities.py
index 350efa68..9a9342be 100644
--- a/cara/tests/test_known_quantities.py
+++ b/cara/tests/test_known_quantities.py
@@ -29,8 +29,9 @@ def baseline_model():
         room=models.Room(volume=75),
         ventilation=models.WindowOpening(
             active=models.PeriodicInterval(period=120, duration=120),
-            inside_temp=293, outside_temp=283, cd_b=0.6,
-            window_height=1.6, opening_length=0.6,
+            inside_temp=models.PiecewiseconstantFunction((0,24),(293,)),
+            outside_temp=models.PiecewiseconstantFunction((0,24),(283,)),
+            cd_b=0.6, window_height=1.6, opening_length=0.6,
         ),
         infected=models.InfectedPerson(
             virus=models.Virus.types['SARS_CoV_2'],
@@ -50,8 +51,9 @@ def baseline_model():
 def baseline_periodic_window():
     return models.WindowOpening(
         active=models.PeriodicInterval(period=120, duration=15),
-        inside_temp=293, outside_temp=283, cd_b=0.6,
-        window_height=1.6, opening_length=0.6,
+        inside_temp=models.PiecewiseconstantFunction((0,24),(293,)),
+        outside_temp=models.PiecewiseconstantFunction((0,24),(283,)),
+        cd_b=0.6, window_height=1.6, opening_length=0.6,
     )