I have a 2010 Routan SEL with the automatic climate control. I get irregular heat from the system. This started a year ago. I flushed the system, replaced the thermostat, replaced the front and rear heater core, and replaced the water pump. I get 180 deg F going into the front heater core but 120 coming out. At the vents I get a range from 80 to 110 deg F but it fluctuates. I also noticed that the temperature gauge fluctuates between 200 and 175 deg F. When we take the system off automatic climate control and set it at the feet and try to recirculate the air the Recirc button blinks and I notice the recirc blend door does not move. I looked at the actuators and they are moving and there is no broken connection between the actuator and door. A mechanic shop reset the head unit and synchronized all the actuators. I feel like there is still an issue with the control system where the mechanic belives it is a coolant flow issue. Not sure where to look next.