diff --git a/components/pid/temp_controller.py b/components/pid/temp_controller.py
index e0b9a16..c7dba24 100644
--- a/components/pid/temp_controller.py
+++ b/components/pid/temp_controller.py
@@ -2,7 +2,10 @@ from components.pid.temp_controller_base import TempControllerBase
 
 
 class TempController(TempControllerBase):
-	def __init__(self, dt, params):
+	def __init__(self, dt, params, model_params=None, theta_amb=20):
+		# model_params/theta_amb are accepted (but unused) for constructor
+		# compatibility with TempControllerSmith - PidFactory.create() calls
+		# either with the same arguments; "Normal" has no internal model.
 		TempControllerBase.__init__(self, dt, params)
 		self.dt = dt
 		self.last_theta_ist = 20