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Controller/Timer: This controls the watering cycles by automatically activating the control valves on the days and times you pre-select, thereby directing when, how long, and how often the irrigation system operates.
Backflow preventer: This device prevents irrigation system water from being siphoned back into the pipe that carries drinking water into your home. All cities have ordinances that require installation of a backflow preventer. Contact your city for permit and installation requirements.
Control valves: Manually or automatically operated control valves are used to turn the water on and off. Automatic control valves are wired to a controller.
Filter: All drip systems need some type of filter to keep dirt and debris from clogging the emitters.
Pressure regulator: Most drip systems operate at low pressure, between 20 and 30 PSI (pounds per square inch). Pressure regulators reduce incoming water pressure to the ideal pressure for the drip system.
Pipe/Poly tubing: This is the main water conduit in a drip irrigation system. It is also called an irrigation line or lateral. Polyethylene tubing and hard PVC pipe are the two most commonly used types of pipe.
Micro tubing:This delivers water from the emitters or poly tubing to the plants.
Emitters: These connect to the poly tubing or micro tubing and deliver water at a slow, consistent rate, usually 1/2, 1 or 2 gallons per hour (gph).
Goof plugs: Goof plugs correct mistakes by plugging extra or misplaced holes in the poly tubing.
Flush cap: A flush cap is attached to the end of each irrigation line so that dirt and debris can be flushed out of the irrigation system.