Troubleshooting Common Issues - Centrifugal Pumps and Controls

Transcription

1 roubleshooting ommon Issues - entrifugal Pumps and ontrols

2 roubleshooting ommon Issues - entrifugal Pumps and ontrols his guide was developed to assist you in troubleshooting common centrifugal pump issues for small turf and irrigation applications (5hp and below). If you need additional assistance, please contact Munro Pump at or contact your local irrigation wholesaler. ommon Issues My pump is running, but the sprinklers are not acting normal. See Reduced Performance (Pg. 4) he pump is running, but there is no water coming out. See Pump Runs ut Water (Pg. 5) he water comes out, then goes away. hen it comes out See Pump Surging/Flow ycles (Pg. 6) he motor just sits there and hums. See Motor Hums (Pg. 7) When I turn the pump on, nothing happens. See Motor Does t Run t ll (Pg. 8) he pump runs for a little while and then stops and then starts again. See Motor ycles and/or thing Happens (Pg. 9) thing is happening. I have a pump start relay. See Startox (Pg. 10) My pump runs for 30 seconds and shuts off and does not restart. See Smartox (Pg. 11) Evaluating the System 1. Have there been any changes to the system environment? a. New fencing Possible post damage to pipework b. dded zones Pump is now undersized c. eration or animals Damage to sprinkler heads or pipework d. Water source Lower levels than usual 2. Look for obvious problem areas a. Leaking from case or seal area b. racked or worn components c. logged filters or screens d. Damaged gaskets in camlocks and o-rings 3. Determine the primary issue a. Reduced Performance (Pg. 4) b. Pump Runs but Water (Pg. 5) c. Pump Surging/Flow ycles (Pg. 6) d. Motor Hums (Pg. 7) e. Motor Does t Run (Pg. 8) f. Motor ycles (Pg. 9) g. Munro Startox (Pg. 10) h. Munro Smartox (Pg. 11) Safety Precautions LWYS turn the breaker off to work on a pump. Some troubleshooting checks require the pump to be energized, be sure the area is secure prior to the task. e sure to turn the breaker off again if problem persists. NEVER examine, make wiring changes, or touch the motor before disconnecting the electrical supply. hermal overload protectors automatically reset and can close the electrical circuit without warning.

3 How o heck Volts Entering Pump: the breaker box. heck for ir Leaks Using Plastic Wrap: Wrap plastic wrap tightly around a potential air leak path (union joint or cam fitting), turn pump lear entrifugal Switch: Debris can get caught in the centrifugal switch inside the motor. soft hammer or 2x4 board can be used to firmly tap the butt of the motor. fter three or four taps, try to engage the motor. If necessary, repeat. ccess the Wrench Slot: heck the motor shaft for a slot to fit an open-ended wrench. his can aid in diagnosis and teardown/assembly procedure. ear Down and Reassembly of a Pump, Including to Replace a Seal or lean the Impeller: seal, clean the impeller, or access the inside of the pump for any reason. ools You May Need pressure gauge on the pump is a good indicator of system performance. Low pressure while the pump is running indicates a suction or obstruction problem. rmal pressure readings at the pump commonly indicate a sprinkler head or pipework problem. Possible Replacement Parts 3

4 roubleshooting Guide - Reduced Performance You cannot always find a suction leak by pressurizing a line. ir can escape even if water will not. Has anything in the system environment changed? Was it fencing, aeration, animals or something similar? Refer to Pump Runs but Water (Pg. 5) heck the pipework for damage or breaks. Repair if needed. Is the performance better? Were new sprinkler heads added to an existing zone? Pump Works Is there a change to the water source? D Reduce the number of heads per zone, change nozzles, or add a seperate zone. Is the performance better? Refer to Pump Runs but Water (Pg. 5) Refer to Pump Surging (Pg. 6) Refer to Pump Runs but Water (Pg. 5) Pump Works Refer to your pump s performance curve. You may need to replace the pump. If the pump is appropriate for the system, refer to Pump Runs but no Water (Pg. 5) D

5 roubleshooting Guide - Pump Runs but Water Is your pump primed? (Is it filled with water?) am fittings are best used with the handles to the top and bottom. It reduces the chance of leaking from the weight of the hose. heck to make sure the valves are open. Does the water flow Fill the case with water. Does the water flow heck the suction assembly for air leaks (tip on Pg. 3) and repair/replace if needed. Does the water flow E Does the pump maintain prime after restarting the pump? heck the suction assembly for air leaks (tip on Pg. 3) and repair/replace if needed. Does the water flow E heck/clean foot valve, filter and strainer for debris. Does the water flow Is water leaking from the pump? heck foot valve, filter and strainer for debris. Does the water flow heck/clean impeller for debris.* Does the water flow Identify the problem, (seal, case, suction line) and repair or replace. Does the water flow E & ontact qualified service heck/clean impeller of debris.* Does the water flow ontact qualified service ontact qualified service ontact qualified service D E *

6 roubleshooting Guide - Pump Surging (Flow ycles) gaskets can harden over time and become brittle, causing air leaks. Is this a new install or has anything changed on the suction side of your pump? *heck/repair gaskets and unions for air leaks. (See Pg. 2) Is the flow normal? E heck the level of the water in the ditch. Is the foot valve fully submersed? heck the suction assembly for air leaks and repair or replace if needed. (See Pg. 2) Is the flow normal? *heck/repair gaskets and unions for air leaks (tip on Pg. 2). Is the flow normal? E Submerse the foot valve. Is the flow normal? ontact qualified service heck the suction assembly for air leaks and repair or replace if needed (tip on Pg. 2). Is the flow normal? heck/clean obstructions in line and foot valve. Is the flow normal? ontact qualified service heck/clean impeller of debris.* Does the water flow ontact qualified service D E * 6

7 roubleshooting Guide - Motor Hums o avoid an unnecessary trip, try jostling any debris inside the pump free before bringing your pump to a repair man. (ip on Pg. 3 lear entrifugal Switch ) Does the shaft spin freely? Firmly tap butt of motor 3-4 times with a soft-faced hammer or 2x4 to jostle free debris. Does the pump turn on? With a wrench in the wrench slot on the shaft, apply gentle torque on the wrench. an you break the impeller free? While the pump is turned on check voltage at the motor with a voltmeter (tip on Pg. 3) Is the voltage the same as indicated by the breaker? Repeat the previous step. Does the motor turn on Does the pump run Remove housing and diffuser to clean.* Reassemble. Does the pump run ake motor to motor shop for diagnosis. all electrician to While the pump is turned on check voltage at the motor with a voltmeter (tip on Pg. 3) Is the voltage the same as indicated by the breaker? all electrician to ake to qualified repair center. ake the pump to motor shop for diagnosis. all an electrician to ake to motor shop for diagnosis. *

8 roubleshooting Guide - Motor Does t Run at ll motor may start with low voltage but cannot maintain running at low voltage. It will eventually wind down to a stop. heck the breaker. Is it on? While the pump is turned on, check voltage at the motor with a voltmeter (tip on Pg. 3) Is the voltage the same as indicated by the breaker? & urn the breaker on. Does the pump run ake motor to motor shop for diagnosis. all electrician to Motor works. Is the pump working? While the pump is turned on check voltage at the motor with a voltmeter. (Pg. 3) Is the voltage the same as indicated by the breaker? & Refer to Pump Runs but Water (Pg. 5) ake motor to motor shop for diagnosis. all electrician to two-pull motor with 60 cycle current will run an estimated 3600 RPM. te: For systems without a pump start relay, also see Pg. 9. For systems with a pump start relay, also see Pg. 10.

9 roubleshooting Guide - Motor ycles and/or thing Happens capacitor start motor has 1.5 times more torque for starting a motor. Does the pump run a short time and then stop? Using voltmeter, check wire voltage at the pump (tip on Pg. 3) re they the same? K & L heck breaker box to assure breaker is on. Does the pump run ompare the "at the pump" voltage (from previous step) to the voltage listed on the motor nameplate. re they the same? V Wiring between pump and the breaker box may be damaged. all an electrician to he pump works! Is the pump controlled by a lawn controller? Motor may be damaged. ontact local ES rated motor shop for assistance. Rewire motor according to nameplate diagram. Does the pump work V Refer to Smartox or Startox (Pg. 10, 11) Is the pump controlled by a float? he pump works! Wiring may be damaged. all an electrician for assistance. Verify float control configuration. Does it work Is the pump controlled by a manual on-off switch? G Start/Stop (Signal) Voltage H Pump Start Relay reaker ox he pump works! all electrician to check wiring. Verify switch wiring and functionality. Is the pump working all electrician to K L he pump works! all electrician to Nameplate (Wiring Diagram)

10 roubleshooting Guide - Startox pump start relay can be signalled by a float switch. Is there a lawn controller? Does your relay click when the lawn controller starts? Is the start/stop signal voltage the same voltage getting to the coil? (24/110/220). G & H to & Is there power at the top of the relay (110/220)? & D Does the signal voltage match the relay coil voltage? S Wiring problem between start/stop signal and Startox. all electrician to Is there continuity from the top of the relay to the bottom? to E or D to F Is the breaker turned on? he pump control works. Refer to pump (See Pg. 2) Replace relay. Is the pump running? Replace the relay. Wiring between the pump and the breaker box may be damaged. all electrician to urn it on. he pump control works. Refer to pump (See Pg. 2) D S G H E F K L te: he Startox & Smartox troubleshooting guides do not apply to 2-wire decoder systems.

11 roubleshooting Guide - Smartox During a normal run cycle, no lights should be lit on the time delay. Should a sensor detect a possible system problem, the on light will engage. If the system is shut down during a cycle both the on and up lights will be lit for the duration of the lawn controller cycle. Does your relay click when the lawn controller starts? Does the pump run at all? Verify that the start/stop signal voltage leaving is the same voltage getting to the relay. G & H to Q & P to R & P to & heck time delay.* Is it working? U, ross M & N heck wiring according to the wiring diagram. Is the wiring correct? Verify voltage matches coil voltage. Does the voltage match? S Wiring problem between lawn controller and Smartox. all an electrician to Is this a seasonal or a first time fill up? See te below. djust or replace the time delay. Does it work U he control works. Refer to the pump (See Pg. 2) all manufacturer for further troubleshooting. he pump control works. Replace the relay. Restart irrigation system and/or increase time on time delay to allow for filling. U heck pressure sensor with a voltmeter for continuity. he pump control works. all electrician to D * urn the time delay down to 5 seconds. Next, cross the red and blue wire. he on light should turn on. fter 5 seconds the system should shut off and both the on and up lights should be on. te: Filling system lines may require multiple run cycles to build enough pressure to initiate the sensor. G H IME DELY PRESES 1 1/10 M Seconds/Minutes UP ON U R Q P S E F I J PRESSURE SENSOR N M K L

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