Key takeaways
- Water comes from your supply through a backflow device to the valves.
- The controller opens one valve at a time, and each valve feeds one zone.
- Each zone has pipe and heads matched to its area and plants.
- Knowing the parts makes it easier to spot a problem.
From the water source to the valves
Most systems tap into the home's water supply and run through a backflow preventer, which protects drinking water. From there, the main line carries water to a manifold of valves, usually in a box in the yard.
Each valve is the on-off switch for one zone. Only one zone runs at a time, so the supply only has to feed that one.
The controller and its wires
The controller is the brain. It keeps the schedule and sends a small electrical signal down a wire to the valve it wants open. A rain or freeze sensor can tell it to skip a run.
If a zone will not start, the cause is often the controller output, the wire, the solenoid or the valve, in that order.
Pipe, heads and nozzles
Underground pipe, usually PVC or poly, carries water from the valve to the heads. Rotors cover large areas with a slow stream, and spray heads cover small areas with a fan of water. Drip lines serve beds and trees.
Heads in the same zone should apply water at the same rate, or one part of the zone will be wetter than the rest.
How the pieces work together
A good system matches the zone size to the water pressure and flow available, groups plants with similar needs and covers every area with overlapping heads. When one of those is off, you get dry spots, wet spots or wasted water.
A walk through the yard while each zone runs is the quickest way to see how yours is doing.
Quick answers
How many zones does a house need?
It depends on the size of the yard, the water supply and the mix of lawn and beds. A design visit sorts it out.
Where is my backflow preventer?
It is usually near the house or the meter, above ground or in a box.
Do I have to turn the system off for winter?
The water has to be cleared from the pipes before a hard freeze, which is why a winter blowout is common.
