Irrigation Troubleshooting Guide RAIN BIRD
RAIN BIRD TABLE OF CONTENTS SUBJECT Page 1 Introduction Section 1 Section 2 Section 3 Section 4 Section 5 Section 6 Section 7 SPRAY HEADS Common problems, troubleshooting 2 IMPACT SPRINKLERS, & MAXI-PAW Operation, common problems, and troubleshooting 3 CLOSED CASE ROTORS T-Bird Operation, arc adjustment, and troubleshooting 5 R-50 Operation, arc adjustment, and troubleshooting 6 R-70 Operation, arc adjustment, and troubleshooting 7 REMOTE CONTROL VALVES Operation, common problems, and trou
RAIN BIRD INTRODUCTION The following pages are a compilation of class information from the Rain Bird ASC seminar “Troubleshooting an Irrigation System.” Its purpose is to serve as a reference manual for troubleshooting problems. We hope that you keep this manual and refer to it when needed. Remember, you don’t have to know the answer, you just need to know where to look for the answer. We also encourage you to share this information with your coworkers.
RAIN BIRD SPRAY HEADS Spray heads are relatively simple to troubleshoot. Below are the most common problems found with spray heads. Misting - This is a result of excessive water pressure. Reducing the pressure may be done in one of two ways. 1. Using the flow control on the remote control valve, or 2. Installing a pressure regulator before or on the valve Inaccurate pattern - This is usually caused by some type of blockage, either in the nozzle itself or in the screen.
RAIN BIRD IMPACT SPRINKLERS All impact sprinklers work in the same basic fashion. This includes impact style rotors as well as most of the different styles or brands available today. The following is a quick overview of how an impact sprinkler works. Operation Water enters the bottom of the sprinkler through the bearing nipple, proceeds up through the body and exits out the nozzle. When the water hits the arm, it is propelled out away from the sprinkler.
RAIN BIRD Common Problems The sprinkler is stuck or won’t return - The most common reason for this is water pressure that is too high or to low. Impact sprinklers can fail under either scenario. To determine what the operating pressure is, a pitot tube and a pressure gauge may be used to get a pressure reading at the head. This is done by placing the end of the pitot tube in the water stream, as close to the nozzle as possible.
RAIN BIRD T- Bird The T- Bird is Rain Bird’s first gear driven sprinkler. It is designed to operate in the 25-60 PSI range and cover a radius of 16-30’. It has a pressure compensating flow bushing, resulting in matched precipitation and pressure activated wiper seal. Arc Adjustment To increase the arc - Keep in mind that the part circle T- Bird comes preset at 180°. Pull up on the stem, and while holding the textured area, rotate the nozzle until it is turning to the right (clockwise).
RAIN BIRD R-50 TROUBLESHOOTING Operation The R-50 is an internal impact sprinkler. This means that there are two small stainless steel balls that act as the drive mechanism. Arc Adjustment To increase the arc - Keep in mind that the sprinkler is preset to approximately 180°. Pull up on the stem, slide the vandal collar out of its groove. Push down on the nozzle slightly, and rotate the nozzle to the right (clockwise). The arc will be increased by the amount the nozzle is turned.
RAIN BIRD R-70 The R-70 is a piston driven, water lubricated sprinkler. The R-70 was designed to emulate, or mimic, our impact sprinklers. Impact sprinklers are considered to have the most efficient water distribution. The R-70 uses only 2% of the water passing through the unit to drive the head. This gives the R-70 a distinct troubleshooting advantage in that it is an excellent closed case dirty water rotor.
RAIN BIRD Common Problems Variable arc - As stated above, the adjustment screw must be returned to the locked (LKD) position when the arc adjustment procedure has been completed. Failure to do so may allow the arc to change. The stem should also be inspected to determine if it is of current design. A prior version had a slip clutch built into the stem. Refer to the water distribution section for further information. Water distribution - The current design for R-70 nozzles are referred to as Phase Ι.
RAIN BIRD REMOTE CONTROL VALVES The valves covered in this section will be electrically operated remote control valves (RCV’s). All remote control valves can be separated into two different types. The difference between the two is how the water enters the upper chamber. The upper chamber is the area between the cover and the top side of the diaphragm. Once the water has entered the upper chamber there are only two paths for it to escape: the manual bleed or the solenoid exhaust port.
RAIN BIRD 1. The plunger is missing or stuck in the up position. Remove and inspect the solenoid. 2. Diaphragm filter plugged. This will prevent water from entering the upper chamber. 3. Flow control turned up too high. The diaphragm can stick in the up position under low flow/low pressure conditions. 4. Constant voltage from the controller. The solenoid will usually be warm to the touch and a slight vibration can be felt if this is happening. 5. Leak between the bonnet and body.
RAIN BIRD CONTROLLERS This section will describe some troubleshooting procedures that will determine if the controller is indeed the bad component in the irrigation system. The controller is usually the first component blamed from an irrigation system failure. Typically, once the controller has been removed and taken to a repair facility, a conservative estimate is that 25% are returned without a defect being found in the controller.
RAIN BIRD Electromechanical Controllers Time and/or day incorrect - As long as an electromechanical controller is connected to its primary power source the correct time and day can be determined upon visual inspection. If this is not the case, check the following: Primary power - Verify that the 117 volt VAC power is on and correctly connected to the controller. The acceptable range is between 105 and 129 VAC. If the voltage is above or below this range, contact a certified electrician.
RAIN BIRD Advance motor - This motor only received voltage and operates when the controller is changing stations and when returning the station dial to the rest position. When checking to determine if the motor is receiving the proper voltage, be sure that the motor is supposed to be engaged at that time. It may be necessary to apply the correct voltage directly to the motor from another source to verify operation.
RAIN BIRD Hybrid/Solid State Controllers Hybrid and solid state controllers are designed to provide the programming versatility that is needed to better protect our water resources. the technology that is necessary to accomplish this makes repairs by untrained persons. The following items should be checked before assuming that the controller is the problem. Visible damage - Inspect the controller for any visible signs of damage.
RAIN BIRD Microprocessor Lockup Problems The microprocessor is the “brains” of the controller. Occasionally, due to electrical problems, the microprocessor will freeze all of its functions. The symptoms of this are: Display blank, (the display does not show any information) or Frozen display, (the display shows erratic information that cannot be cleared or changed from the keypad) and The controller will not perform any of its programmed functions.
RAIN BIRD VOLT OHM-METER ( VOM ) A volt ohm-meter is an inexpensive piece of test equipment that is capable of measuring AC volts, DC volts, and resistance. By learning how to use this equipment, it is possible to troubleshoot controllers, solenoids, field wiring, and to verify AC and DC voltage levels. There are two styles of VOM’s, analog and digital. An analog VOM is the style that has a needle that moves across a face (similar to a speedometer). The DMM (digital multi-meter) has a digital display.
RAIN BIRD Hook-up Your VOM will have one jack labeled (-) COM, into which the Black lead will be inserted. Insert the Red lead into the jack marked (+) V - Ω - A. this same setup is used to measure AC volts, DC volts, and resistance. Taking measurements AC volts - Set the dial to the appropriate VAC scale. For example, if 117 volts is expected to be measured, the dial must be set to a scale above that. WARNING if the dial is set to the 50 ACV range and 117 volts is measured, damage to the VOM is likely.
RAIN BIRD Resistance measurements 1. Disconnect the common wire from the controller. 2. Set the VOM to the Rx1 scale and zero the meter. 3. Connect one of the VOM leads to the common wire (not the controller common terminal). 4. Touch the second VOM lead to each of the station terminals and record the resistance readings. Compare your readings to the acceptable range of 20-60 ohms. 5. If the measurements are within the acceptable range then the electrical circuit for that station is good.
RAIN BIRD 621970 Relay Description This relay has three sets of contact “families” called poles. Terminals 1, 4, & 7 make up pole #1 2, 5, & 8 make up pole #2 3, 6, & 9 make up pole #3 (Refer to figure 1) (Refer to figure 1) (Refer to figure 1) Each pole is electrically independent of the others. This means that there are no wires that internally connect the three poles.
RAIN BIRD OPERATION In its “rest” position within each pole, the wiper is making contact with its NC contact. Example: Pole #1, terminal 7 is touching terminal 1; pole #2, terminal 8 is touching terminal 2; pole #3, terminal 9 is touching terminal 3. Remember: the three poles are not connected to each other. Refer to figure 2. When 24 volts is applied to the coil (terminals A & B), the relay will be turned on, or energized. Once the relay has been energized, the coil will develop a magnetic field.
RAIN BIRD RELAY USES One of the most common uses of the relay is as a pump start relay. The pumps used for irrigation systems operate on 117 VAC or higher. The contacts of the 621970 relay are rated at 10 amps (per pole) at 240 VAC. If your pump or other devices has a higher current or voltage requirement, then contact an electrical supply for the availability of a different relay. Relays are available in a very wide range of shapes, sizes and electrical characteristics.
RAIN BIRD When the controller is not operating, the relay will not be energized. The 117 VAC needed to operate the booster pump is being interrupted at the relay. Refer to figure 5. As soon as the relay is energized by the controller, the 117 VAC is allowed to pass through the relay to the booster pump. Refer to figure 6.
