Question
The system starts at pproper time on proper days and runs for programmed duration, however after zone 4 finishes the system immediately cycles through the 4 zones a second time.
I expect the system to be near 20 years old. Am I due for a new
controller???

Answer
Hey Duane, it sounds like you have more than one start time programmed. Make sure you only have a start time for start time #1 and not a start time #2 or #3. If for instance you have a start time at 7:00am and a second start time at 7:15am. after the first start time at 7:00am runs, it will run a second time because you have a second start time programmed. Take out the other start times, and it should only cycle once. Good luck and have a great day.