I just completed my electric brewing system and I have been trying to test it prior to brewing the first batch. However, this is my problem..... I have been unsuccessful in getting the PID controllers to Auto tune. I heated the water up to apron 15 degrees below target temperature and set the controller to "2" to start the auto tune in 10 sec. I let it flash an continue to run. per the instructions it will run for up to 30 minutes and then it will be complete. However, it kept heating up until it was almost boiling until is shut it off. looking for any suggestions on why this is not working correctly.