Rotors

Rotors or rotary sprinklers use slow rotating, high-velocity streams to distribute water over large areas in circular or semi-circular patterns. The diameter of coverage can range from 30 to 200 feet or more depending on size and available pressure. Commercial and residential lawns that have large open areas can benefit by this type of irrigation.

Benefits:

• Biggest benefit is you are able to keep the piping further away from trees and roots which can cause major damage to both. (See repairs)
• Less heads will cover larger areas of turf.

Drawbacks:

• Takes three to four times as long to water same area vs. spray heads.
• More water loss due to evaporation and wind effects.
• Complete coverage is more difficult due to trees and other obstructions.
• Low precipitation rates in some climates.

Very important information about rotors!

When we first started in the irrigation business we almost exclusively used sprays. After years of repairs from root damage costing customers thousands of dollars, we have exclusively started using rotors where possible. This will not only save you repair costs but any damage to your valuable landscape.

Rotors need to be installed correctly. We usually don't space them more than 25 to 30 feet max. I have seen them installed 40 to 50 feet apart which is no different than companies stretching sprays more than 15 feet. This is when you start seeing green circles. The water just won't cover.

Rotor also need to be nozzled properly.
It is very simple and amazed us as to how many people in the business just don't know. Rotors come with various nozzles allowing so many gpm (gallons per minute) through them and according to the pattern you are using you match it accordingly. Ex: A rotor that turns 360 degrees or full circle takes four times as long to water the same spot as a rotor turning 90 degrees or one quarter circle. The 90 will water that area three more times before the 360 reaches that area again. A number 5 nozzle on a hardie puts out 3.8 gpm at 30 psi. If you used that same nozzle on a 90 degree nozzle it would put 3.8 gpm in the same area but do it three more times before the 360 reached that area again. You have to put a number one on the 90 which puts 1 gpm in that area to match the precipitation rate.