Irrigation controllers are essential components of a Irrigation Sprinkler System.When DIY sprinkler system, the following article can help you better understand how to choose, install and replace a controller / timer.

What is an Irrigation Controller?

Hunter Pro-C Timer

Irrigation controllers, also known as irrigation timers or lawn sprinkler system timers, are the nerve centers or brains of the sprinkler system. Sprinkler system timers send electric signals to the irrigation valves. The valves regulate the flow of water to the sprinkler system.

Irrigation Sprinkler System timers are the devices that allow you to set a watering schedule to meet your needs. You can set the days you want to water, the time of day you want the sprinklers to come on, and how long you want them to apply water.

Sprinkler system controllers may be mechanical, partly automatic, or fully automatic. Although irrigation sprinkler system timers are largely maintenance-free, the home or property owner might wish to upgrade and replace irrigation controllers or install irrigation controller parts or extra features. Sprinkler timer installation or replacement is very straightforward and easy and can be done by either the homeowner or by an irrigation professional.

How to Choose an Irrigation Controller / Timer

The only important decisions you need to make when selecting a controller / timer are as follows:

1. Controller mounting location: indoor or outdoor
2. Number of stations or zones – must be at least as many zones or areas your sprinkler system is broken up into.
3. Number of programs (1, 2, 3, or 4) – should have at least 2 or more programs to give you the watering flexibility you want or need. The programs on a controller are very different from the number of stations on a controller. This is explained below.

IMPORTANT: The rest of the features you can choose from on a controller are just for added benefits or increased flexibility.

Indoor vs. Outdoor models
Sprinkler system controllers come in a wide range of makes and models. Choose lawn sprinkler system timers depending on the size of the sprinkler system and the user’s needs. Lawn sprinkler system timers come in two different types: indoor models and outdoor models. Indoor sprinkler system timers need to be sheltered from weather, and can be conveniently plugged directly into a 110-volt outlet. This is because they come with an external transformer as part of the plug-in cord that converts the 110-volts to 18 volts. Typical locations for mounting indoor timers are in the garage, building, covered patio, shed, pump house, closet, etc. Outdoor lawn sprinkler system timers are convenient, weather resistant, durable, and typically need to be hard wired for power instead of plugged into a 110-volt outlet. This is because the transformer is located inside the protective weather resistant cabinet and it is assumed that the electrical connection will need to be weather resistant also.

Outdoor controllers can be used as indoor controllers just by adding a pig tail (3 prong plug and power cord) to the power wires of the timer. People do this all the time to be able to get all the benefits of an outdoor timer with a weather resistant cabinet and typically all kinds of added features. An example of this is the Hunter ICC model controller which is one of Hunter’s best controllers. It has so many nice features that people will just add a pig-tail and make it an indoor timer.

Controller Stations
Typically, residential systems use irrigation controllers with 2 to 9 stations, while systems for commercial or public properties can have 32 – 48 stations or more. Each station regulates one zone or area of the lawn sprinkler system. When selecting irrigation controllers, know how many stations the system needs. Choose a sprinkler timer with extra stations, in case of later expansion.

Controller Programs
The number of programs a controller or timer typically has can range from 1 up to as many as 4. They are usually labeled as Program A, B, C, and D. Some controllers only have 1 program while most have at least 2 or more. A program is a set of watering instructions for stations that will run on the same days. When you set up Program A on the controller, you are setting the days you want to water, the time of day you want to start watering, and how long you want to water. If you have a controller with two programs, the lawn areas can be set up to be watered every day on one program and the flowerbeds and shrubs every other day on the second program. When a controller starts a program, it will go through the entire program before stopping or repeating the program.

Types of Controllers – Mechanical or Solid-State (Digital)

Some irrigation controllers are fully digital, including easy touch screen features. Digital sprinkler system controllers with basic features are suited to a more conservative budget. Other lawn sprinkler system controllers have an array of features and options for convenience and ease of operation.

Mechanical sprinkler system timers use manually-operated sliders and switches for programming. An electromechanical controller uses both an electric clock and mechanical switching. That is to say, they are made of a motor, wheels, dials, gears, and pins. These controllers are typically, easy to understand how to operate and program, and are less susceptible to power spikes and surges, but are much more limited in features than solid-state digital irrigation controllers.

Solid-State controllers have digital readout screen, have no moving parts, and use integrated circuits for the clock, memory and control features. These controllers are adaptable, offering many more features at a reasonable cost. More advanced Solid-State controllers such as Smart Controllers can adjust the watering schedule automatically throughout the year. Still other controllers operate solely on battery power, for areas with limited or no electricity. Solar-powered controllers are also available.

Features Available on a Controller

Some controllers come fully loaded with features for efficiency and convenience of operation. In others, extra features may be optional. Key features available on a controller can include:

• Clock and calendar settings
  The user can program watering times, control watering cycles, and make seasonal adjustments.
• Manual start and manual station operation
  The user can operate the stations or start the automatic cycle without affecting the programmed start time. This is helpful when you need to do some maintenance to your system. This feature makes it easier to check for leaks, misaligned or broken sprinkler heads and even perform basic tune-ups steps such as adjust spray patters and replace nozzles.
• Master Switch
  The master switch overrides the automatic functions of the stations.
• Master Valve Control
  The master valve prevents flow to the system, in case of water problems or system failure.
• Station Omission
  The user chooses which stations operate, and which do not.
• Pump Start Lead
  This turns on a pump start relay whenever a station activates, to combine irrigation and pump control. A Pump Start Relay is an electronic device that uses a signal current from the irrigation controller to activate a pump to provide water to the irrigation system. Never connect the controller directly to a pump as damage to the controller will result.
• Rain Sensor
  A rain sensor shuts down the irrigation system if it detects rain. The purpose of a rain sensor is to stop watering when precipitation is sufficient. Most controllers allow for a sensor to be connected directly to the controller and allow you to easily override the sensor by using a Rain Sensor Bypass switch on the controller.
• Battery backup
  The controller reverts to battery power in case of power interruption or outage.The battery typically will just allow the timer to maintain the time, date, and watering schedule. On some controllers it allows the user to program the controller without AC power. IMPORTANT: watering will not occur without AC power. The battery only keeps the time, date, and watering schedule in memory until the AC power is restored or the battery dies.
• Non-Volatile Memory
  The controller retains its program data without a battery, even if the power fails.  The non-volatile memory allows the timer to maintain the time, date, and watering schedule indefinitely. IMPORTANT: watering will not occur without AC power.
• Delay
  The delay feature allows time for valves to close fully in one zone, before opening the valves in another zone.

Where to Buy a Controller / Timer

For more information about irrigation controllers, options and features, or to purchase a new irrigation controller or sprinkler timer, go to www.SprinklerWarehouse.com.
If you need more irrigation help, questions about irrigation system repair, or how to install a spinkler system, please visit IrrigationRepair.com

Irrigation Sprinkler System Guide
Irrigation valves or lawn sprinkler valves are an essential component of lawn sprinkler systems. They control the flow of water in lawn sprinkler systems. Sprinkler system valves come in a variety of models, including below ground inline valves and above ground anti-siphon valves.

Available in solid brass or durable plastic, sprinkler valves operate from a manifold above or below ground to regulate water flow to the lawn sprinklers.

Shop for Anti-Spihon Valve or Inline Valves

Lawn sprinkler systems may be manual or automatic. Automatic lawn sprinkler systems consist of the controller / timer, the sprinkler valves, the pipes, and the lawn sprinklers. Each valve controls a different zone, or area, of the lawn sprinkler system. The controller sends electric low voltage (24 volt AC) signals to the valves, telling them to open or close.

Sprinkler valves come in many different styles. Globe or angle irrigation valves work with a separate backflow preventer, and anti-siphon valves have the backflow preventer built-in. Rain Bird valves, Toro valves, Hunter valves, Irritrol valves and Weathermatic valves are all reliable, well-known products that, with proper maintenance, will last for many years.

Irrigation Valves – Types of Valves and What They Are Used For Shut-off Valves

Emergency shut-off valves stop the flow of water to the irrigation system. If repairs are needed to the sprinkler system valves or any other part of the irrigation system, the shut-off valve prevents the need to turn off the entire water system to the house or what ever else the water feeds.

Emergency shut off valve: You should install this sprinkler system valve as close to the water source as possible and should be the same size as the pipe you are installing it on. If you do not install this valve, you will have to shut the water off to the entire house when you want to make repairs or work on the irrigation line. You only need to install one of these shut off valves for your irrigation system and it will either be installed under ground in a valve box or in the basement depending on where your water supply connection is located.

If you are using a water meter from the city as your source of water, it is best to tee off the pipe coming out of the water meter (the one headed to feed the house) as close to the meter as possible and use the tee to start the water supply to the sprinkler system. In this case, you would install the shut off valve close to the tee on the line headed to feed the sprinkler system. Some people will put the tee close to the meter but then install the shut off valve just before the backflow device which may be installed on the side of the house. If you are in an area that freezes and you will be using the basement water supply piping as your sprinkler system water supply, install the shut off valve in the basement on the piping before the backflow device.

The most popular valves used for this purpose are the gate valve, ball valve, disc valve or butterfly valve. The gate valves are the most inexpensive and tend to NOT Close completely plus they are typically metal and corrode quickly making it difficult if not impossible to use. Your best bet is to use a PVC ball valve (highly recommended) since they are a more reliable choice. They close completely and they do not corrode or rust which means you should always be able to open and close them easily even when buried under ground in a valve box.

Control Valves (as known as Zone Valves)

Irrigation control valves are used to turn the irrigation system on and off and there are two different types to choose from:
1.) Globe and Angle Valves
2.) Anti-Siphon Valves

The globe and angle valves come in any size and are usually installed under the ground or in a vault or valve box. Since there is not a backflow preventer attached as part of the valve, you will need to add that separately. This is the most common type used in sprinkler systems. However, you may choose to use the anti-siphon valve, which comes only in 3/4- and 1-inch sizes and comes complete with a backflow preventer. The anti-siphon valve absolutely must be installed above the ground and must also be 6 inches higher than that of the highest sprinkler head.

Valves come in brass and plastic; the most common ones used today are the plastic ones. The brass valves will ultimately last longer if installed in the sunlight. Both types are reliable for an automatic system, but for manual systems the manual brass valve is the best choice because it lasts much longer. Valves today are fairly maintenance free.

As for pressure losses and valve size, the automatic valves should be sized based on the manufacturer’s flow range chart and will not necessarily be the same size as the pipe. However, it is more common that it will be the same size as the pipe it is installed on. A manual valve is much more adaptable than the automatic and you do not have to depend on electricity to power it, rather it is done manually, hence the name. A manual irrigation control valve needs to be either an angle or globe type with replaceable rubber seals and not the gate type as the gate valve is not made to be opened and closed regularly.

Above Ground Anti-Siphon Valves

Anti-siphon valves have a built-in backflow preventer to keep irrigation water from washing back into the household’s main water supply. Use Anti-Siphon valves in locations where the use of a pressure vacuum breaker (PVB) or double check valve is not required by city codes. Some areas of the country, such as in California and Arizona, require backflow prevention for every zone. Check your local city codes to determine what type of valves are required. The Anti-Siphon valve is a combination valve that has an atmospheric vacuum breaker and an electronic control valve all in one unit. It provides backflow prevention on every zone, saving costs by eliminating the need for a separate backflow preventer. Anti-Siphon valves are installed above ground and will prevent back flow if properly installed. Anti-Siphon valves should always be installed at least 6” above the highest head on the valve line, and should never have another valve installed further down the line from the main valve

Below Ground Inline Valves

These valves are often globe valves or angle valves. Inline valves are installed underground, protected by a valve box. Below ground inline valves require a separate backflow preventer, installed to meet local bylaws and regulations. However, the great thing about inline valves is that they are typically less expensive than anti-siphon valves and you can install them in the middle of each zone (or section) of your sprinkler system which keeps the pressure loss in the zone more balanced and uniform. Furthermore, you save money on pipe since you end up with one mainline traveling through your yard supplying all you valves instead of having multiple runs of pipe in the same trench heading from the anti-siphon valve manifold to each zone. Plus you only need one backflow preventer device protecting the whole sprinkler system instead of paying for one on each anti-siphon valve. Using a single backflow device with inline valves is a better way of installing your system and it will last longer than the anti-siphon valve plastic backflow device which relies on gravity and has no other parts to assure it functions properly. One other important note: anti-siphon valve back flow vales can not be tested to see if the backflow prevention is functioning, however, backflow devices purchased separately to be used with inline valves can be tested to assure they are functioning correctly. Using inline valves is a more professional way of installing your sprinkler system.

Globe Valves

Globe valves once had a spherical body, but modern globe valves have changed in shape, and only the name remains. Water flows through the valve without changing direction. The two halves of the valve body are separated by an internal baffle. A movable plug, or disc, screws in to shut off the valve. In manual globe valves, the plug connects to a stem which operates by hand wheel. In automatic globe valves, the stem is smooth.

Angle Valves

Named for their angular design, angle valves direct the flow of water at a right angle to the valve. Water flows into the valve, then changes direction 90%.

The Valve Manifold

The manifold is a group of control valves attached to a pipe. Water enters the manifold from the main water supply line. The water is then routed through the control valves. The valve manifold may be below or above ground.

To build the valve manifold, use a length of PVC pipe. Space the valves about three to six inches apart. The number of valves determines the overall length of the manifold pipe. Include an extra connection or two, for possible expansion to the system later. Save time and work by purchasing a ready-to-install manifold kit, which includes the sprinkler valves and all necessary parts and instructions. Many manifold kits have a flow control feature, to help conserve water.

Valve Boxes

A valve box is a plastic cover that protects the valves and wiring from damage and debris. Above ground, the valve box also protects the valves and manifold piping from harsh sunlight and inclement weather, or damage by accident, animals or vandalism.

Backflow Prevention Devices

Backflow prevention devices will prevent irrigation water from lawn sprinkler systems from backing up into the drinking water. Irrigation water may contain contaminants such as pesticides and other chemicals, as well as waste products and dirt. While these elements don’t harm the lawn, they create health risks in public or household drinking water.

If you go with Hunter, make sure you use the Pros series or the Institutional series sprays for areas under 15 feet radius, and as far as their rotor models You can not go wrong with the PGP series, or I-20 series rotors.

If you go with Rain Bird, make sure you use 1800 series sprays for smaller areas (less than 15 feet radius) and as far as their rotor models You can not go wrong with the Rain Bird 5000 series or the 5000 Plus Series Rotors.

Please visit IrrigationRepair.com to learn more about irrigation sprinkler system.