Why is My Controller Acting so Crazy?

When things start going wrong with an irrigation system, the controller is usually the first thing people blame.  Over the years, irrigation controllers have become much more dependable.  This isn't saying that the controller isn't the problem, it's just that the real problem is often elsewhere.  There are some simple steps to narrow down the source of the problem depending on the symptom.

The irrigation keeps starting over again after it's finished:
This is almost always caused by extra start times being accidentally entered.  Check the programming to be sure that it contains only the start time you want.  Delete any unwanted start times.  Duplicating information in more than one program can also cause this.  Remember that a dual program controller is like two controller in one box.  If you have the same information in two programs for the same stations, you have told it to run them twice.  This can be an easy mistake to make by not noticing which program is showing in the display when entering information.

The irrigation seems to run at strange times:
Again double check to make sure that only the start times you want have been entered.  Remember to check in all of the programs that your controller has available.  Also double check that the start times are correct as to A.M. and P.M.  If this seems to be OK then check to make sure the controller is displaying the proper current time and day.  If this is incorrect re-set it and check on it the next day.  One of the most common reasons your irrigation will run at strange times is if you've lost your programs and the controller has reverted to the factory default.  Occasionally the timing portion of the digital processor will malfunction and cause the controller to either run too fast or too slow.  If this is the case, contact the manufacture to locate a service center.

The irrigation runs longer than it's supposed to:
Check the station run times and make sure that they are correct.  If they are, check to see if your controller has a water budgeting feature.  If for example you have ensured that the run times are entered as ten minutes but they always run for twenty, the water budget may be set to 200%.  This feature won't physically change the run time you have entered, but it will run the percentage of that time.  Most controllers that have this feature will have an icon or symbol in the display to alert you when it is different than the normal 100%.

For more informative answers to questions contact the University of Arizona, Maricopa County, Cooperative Extension Service at (602) 470-8086.