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Quick Tips For Simple Sprinkler Tune-Ups

Keeping your irrigation system working properly is very important in order to conserve water and money. There are is plenty of tips and advice to follow in order to keep your irrigation system working efficiently. This article explains how to tune up a sprinkler system. Before explaining each tip, there are some terms that will be helpful if understood.

Useful Sprinkler System Terms You Should Know:

  1. Spray-type sprinklers- better known as sprays, create a fan-shaped spray pattern, much like a shower nozzle spray.
  2. Rotor-type sprinklers or rotors- are often used for very large areas. It also has one or more streams of water that rotate over the landscape.
  3. Valve circuit or valve zone- a group of sprinklers that are all turned on and off by the same valve. A sprinkler system must be divided into zones since there is not enough water pressure to run all the areas of your yard at one time. Dividing the yard into common areas allows you to have more control over how much water you apply to each area. A typical yard is divided at the front, back, front flower beds, back flower beds, both sides of the house, parking strip, and down the edge of the driveway.

A well-designed and well-functioning system should apply water uniformly over your plants. It should work so that each plant’s needs are met. The system should also meet the needs of each type of soil.

Detecting some problems may be easy, including broken nozzles, clogged or blocked ducts, or geysers shooting up from the nozzles, instead of spraying as usual. Or it may be as simple as adjusting the nozzle or spray level to make sure areas that don’t need water aren’t getting them, like sidewalks, streets, etc.

However, there are also problems that may not be quite so easily noticeable. By manually starting your system monthly, or using the “test” mode on your irrigation controllers, you can cycle through each zone and make sure they are working properly.

Below Is A List Of Some Of The Problems You Should Be Looking For:

Spray heads or rotor heads that are too low:

  •  If the heads are too low they will not pop up over the top of the grass and spray a proper pattern. The grass can intercept the spray pattern and cause the spray to fall short.
  • It could cause the area around the head to flood while the area farther from the head to be dry. You will need to raise any head that is too low by digging it up. Then you will need to replace the riser under the head with a taller riser.
  • An easier method is to dig up the head and unscrew it from the old riser. Then replace the riser with a Hunter pre-made swing joint.

Spray heads or rotors that are out of adjustment:

  • This causes them to spray areas that should not be watered or to spray too far or too short. Any spray or rotor out of adjustment should be adjusted by following the directions for the type and brand of head you have.

Zone valves that are leaking by allowing water to puddle around the lowest spray heads or rotor heads:

  • If the valve does not close all the way it will allow water to leak by like a dripping faucet. The water will travel in the pipe to the lowest sprinkler heads in the zone. Then leak out the heads slowly causing a puddle or constant wet spot around the heads.

Zone valves that either will not turn on or will not shut off:

  • This is a common problem after the valves have become old. The way to fix this problem is to locate the valve for the zone and replace it. You can do this either by cutting it out or replacing it. You could also buy the exact model valve and use the top and internal parts from the new valve to replace the old parts. (Diaphragm and solenoid).

Controller or timer that will not work properly:

  • If the controller does not turn on either it is not getting electricity or it needs to be replaced.
  • If the controller comes on but it blows a fuse while trying to water an area then you will need to determine if you have a zone valve that needs to be replaced or if you have a wiring problem. In this scenario, the wiring problem would be between the controller and the valve zone.
  • You would also need to check for valve replacements and wiring problems if the controller indicates that a particular zone has a problem and keeps skipping that zone.
  • Almost always it is the solenoid of the zone valve that needs to be replaced.

Additional Steps To Take While Tuning Up Your Sprinkler System:

Turn on each zone valve, one at a time to inspect the zone for problems:

  • If you have above-ground zone valves, carefully inspect the irrigation control valves for leaks, drips, or puddles around the valves. In the event that you see leaking valves, you will need to replace them. If you have below-ground valves, you can skip the valve inspection if you do not know where they are located.
  • Below ground valves typically do not leak around the valve. Instead, they tend to have problems like not turning on or shutting off. They could also not be shutting completely which is indicated by water puddling around the lowest heads in the zone.
  • Some people say that you may be able to fix leaking valves by opening them up and cleaning the diaphragm, which will rid them of debris. You should replace the top of the valve (solenoid, diaphragm, and valve top) using the parts from a new valve of the same brand and model.
  • If you are going to take the time to locate and open the valve, you should replace the parts. The parts are inexpensive. Cleaning the parts of a valve does not repair a deformed diaphragm or weak solenoid. These areas are typically the cause of a leaky valve.

With spray-type sprinklers, you can remove the nozzle from the head and clean the screen under the nozzle. Use a bent paperclip to remove the screen:

  • An old toothbrush does a great job cleaning the filter as well. Check the nozzles and make sure there is no debris blocking them. If you have any doubts about a nozzle, the best option is to replace it.
  • Rotor-type sprinklers have a filter and screen that can be cleaned. Although depending upon the type of rotor, a special tool may be required. It can be trickier to successfully clean rotors without getting additional debris into them. Do not attempt to clean them unless you are certain they need it.

Rotor screens typically only need to be cleaned when you are using dirty water (Ponds, lakes, sandy wells) as your water supply:

  • If you are using the water from the city main, you should not really ever have to clean a rotor screen.

It is also necessary to adjust the sprinklers to make sure only the area needing water is being irrigated:

  • All too often areas like sidewalks, streets, and decks are receiving water from the sprinkler systems, which is wasteful. In order to adjust spray sprinklers, you must turn the adjustment screw on the top of each spray nozzle. If the mist is a problem, turn the screw clockwise.
  • For rotor sprinklers, turn the radius adjustment screw clockwise just until it touches the water stream. Then turn the screw counter-clockwise just until it is not touching the stream. This is the best position for the screw and should be left there in most cases. It may take a few tries to find the best amount of adjustment for the screws.
  • If the screw is too far into the water stream, it can cause dry areas. If it is not far enough, the pressure can be too great. You should always check the water pressure to make sure it is where it needs to be. Overgrown grass and shrubs can easily block areas of the sprinkler causing the water pressure to be compromised.
  • Overgrown grass and shrubs can easily block areas of the sprinkler causing the water pressure to be compromised.

Adjustments to the direction of the spray a rotor or spray head may need to be corrected:

  • All rotors have a fixed side where the rotation stops and a side that opens up for more rotation. An example is a Hunter rotor that has the right side as the fixed side and it opens to the left for more of a rotation angle.
  • Rain Bird has the left side as the fixed side. It opens to the right for more of a rotation angle. By digging a small area around the body of the sprinkler, adjust the position of the fixed side of rotation. Now line it up with the boundary you are trying to water along. Then adjust the head to spray more or less of a circular pattern. Do this by using the adjustment on the top of the rotor. Follow the manufacturer’s directions for specifications.
  • Then by using the soil from which you dug, you can replace it to hold the head in place. Another way to realign the fixed stop of the rotor head is to turn the whole sprinkler body assembly and the fitting below it left or right to the desired position. This may require temporary removal of the soil around the sprinkler to allow you to grip the sprinkler housing.
  • Another way to reset the fixed side of the rotation arc is to unscrew the body cap counterclockwise and remove the internal assembly from the body.
  • Once removed, rotate the nozzle turret to the fixed stop, and screw the internal assembly back into the body with the nozzle aligned to the fixed side of the area you want to be irrigated. At this point, you have realigned the fixed side arc stop, and you can adjust the opposite arc to an appropriate setting.

For spray heads, the direction of the spray pattern can be adjusted by grabbing the pop up shaft while it is spraying and rotating it to the correct direction:

  •   It will typically make a clicking or ratcheting sound but that is okay it is designed to sound like that as you forcefully rotate the pop-up shaft. There may be times when there may be issues with the landscape that surrounds the sprinklers.
  • Try to keep obstacles from obstructing your sprinkler heads, or consider retrofitting your sprinkler system in order to better fit the needs of its surroundings.
  • Additionally, make sure that the heads are placed for “head to head” coverage. This means that the water from one head reaches all the way to the next sprinkler, with a 100% overlap in coverage. Another important step is to make sure your sprinkler heads are not tilted and are in the correct position.
  • If the heads are leaning to the side, they need to be corrected so they are perpendicular to the ground. If they are not properly positioned, they can create dry spots and wastewater.
  • However, if the sprinkler is located on a steep hill, some tilting may be necessary to make sure all areas are reached. Common sense can be used to determine if this is necessary.

Each year you should check the battery in your system, and replace it at least every two years:

  • Set the irrigation controller and make sure it is on the current date and time. If after a power outage the system does not go back to the correct time, the battery needs replaced.
  • You can also set the days that your plants need to be watered, as well as the amount of water the plants should receive. A good rule of thumb is one inch of water per irrigation cycle. This will moisten the soil around 8-9 inches deep, which encourages deeper rooting. This will in turn make the area more tolerant of droughts.
  • In order to figure out how to maintain the system so that one inch of water is dispensed, you will need to calibrate your system. This involves operating your system and using gauges to collect the water and measure it.
  • By timing how long that takes, you can determine an average amount of time in which to set your system. Between 4-7 A.M. is the best time to water plants, because evaporation is reduced.
  • If you want to figure a precise time, you can figure the run times from each zone of your system and subtract it from 7 A.M. This should give you a good idea of what time in the morning you should start your system.
  • Don’t be afraid to only water on an as-needed basis, however.

A rain sensor is a great way to avoid over-watering:

  • These sensors can be easily installed in an area such as attached to the edge of a roof, pointed toward the sky. If installed properly, it will prevent your irrigation system from watering during or immediately after heavy rain.
  • You can adjust the sensor to stop irrigation after an inch of rain as well. Make sure to test it monthly to ensure it is working as well. All of these maintenance procedures are very easy to detect.
  • Regardless of the problem, it is important to take measures to quickly correct the issue so that you are making the best use of your irrigation system possible.
  • Keeping your system properly tuned will save you both time and money in the long run.