There is no definite time a sprinkler system should run. The best way to determine if your lawn is getting enough water is to do a “Catch Can Test”.
When using an automatic irrigation system we use the rule of thumb to allow 15 minutes for spray heads to run and 45 minutes for rotor heads to run. Rotor heads are designed to irrigate the grass and lawn areas. Because they are watering a larger area they need to run for a longer period of time. Spray heads are designed to irrigate small areas or for landscaped areas and provide a mist of water. They need to run a shorter period of time then a rotor head does.
Using a programmable timer will help you set each zone for optimum worry free watering. If you need help setting your timer please let us know.