Jet Pump Troubleshooting
Jet pumps can be used for several different types of applications. Whether you are using a jet pump to supply water to your home from a water well or irrigate a garden, crops, or landscaping, you will need to know some common jet pump issues and identify ways to troubleshoot to keep your pump in top working condition.
Here are some common symptoms, possible causes, and corrective actions for maintaining a jet pump.
Symptom 1: Jet Pump Will Not Star
If your jet pump will not start, there are a few possible causes:
- System pressure has not dropped to switch's "On" or "Cut-in" pressure.
- Fuse or circuit breaker in your fuse box or breaker box has blown or tripped.
- The pump's motor is set to incorrect voltage, or, voltage being fed to motor does not match the motor's rated voltage.
- The hose from the pump body to the pressure switch is blocked, clogged, or frozen or has come off one end.
- The pressure switch contacts are dirty or burned.
- The power wires are loose or disconnected.
- The starting component of the pump's motor has failed.
- The pump's motor has failed.
Go down the list of possible causes to determine the problem with the pump.
Has the System Pressure Dropped?
- The zone valve may not be opening to allow water to move. Try checking or repairing the zone valve.
Has the fuse or circuit breaker blown?
- Check all wiring, pressure switch, and motor to make sure there aren't any loose wires or connections.
Is the Motor Set to the Wrong Voltage?
- Relieve pressure from system by removing the hose from the pump body and pressure switch and see if you can blow through it. If you cannot, it's clogged. Remove whatever is clogging it and reinstall the hose.
Are the Pressure Switch Contacts Dirty or Damaged?
- Measure the voltage on the motor side of the switch to see if the proper voltage is getting through. If not, replace the pressure switch.
Are Wires Loose or Disconnected?
- Check the voltage at motor (and/or pressure switch) to determine which wire(s) are loose and repair as needed.
Has the Motor's Starting Component Failed?
- Test the motor's capacitor and start contactor to see if they are functioning properly. Replace as needed.
Has the Motor Failed?
- If everything else checks out okay, then the motor on the jet pump has probably failed. Replace the motor or the entire pump.
Symptom 2: Jet Pump Motor Runs but No Water is Being Delivered
If your jet pump sounds like it's running, but you aren't seeing any water coming out, there are a few possible causes:
- The jet pump has not been primed.
- The jet pump is sucking air.
- The depth-to-water in the well is too deep.
- The check valve is installed upside down or is stuck in the closed position.
- The pump motor is running on the wrong voltage.
- There is too much restriction in the suction pipe.
- The check valve, tee, or elbow is installed too close to the pump inlet.
- The suction pipe is not far enough down into the water source.
- The suction pipe is frozen.
Has the Pump been Primed?
- Follow the directions in your owner's manual regarding priming the pump.
Is the Pump Sucking Air?
- Your suction pipe may have small leaks around the joints or other connection points where air can be pulled in. The entire length of the suction pipe and all fittings must be completely air tight. You can test this by wrapping every joint with plastic wrap to temporarily seal air leaks.
Is the Well Water Too Deep?
- The depth-to-water is the height in elevation from the pump to the surface water source. Some jet pumps are not powerful enough to pump water more than 25' up. Check the requirements for horsepower, GPM, and PSI.
Is the Check Valve Installed Upside Down or Closed?
- The pump's check valve must be installed in the direction of water flow according to the arrow on the valve.
- Make sure the valve is able to open and allow flow.
Is the Motor Running on the Wrong Voltage?
- For dual-voltage motors, confirm that the motor is set to the same voltage that you have it connected to.
- For single voltage motors, make sure you have connected the same voltage that the motor is built to accept.
Is there Too Much Restriction in the Suction Pipe?
- Using a suction pipe that is too narrow, too long, or has too many elbows can cause restriction in the pump. Never use a pipe that is narrower than the suction port.
- Limit the number of elbows.
- Keep the suction pipe as short as possible. If you do have a long suction pipe, increase the pipe size from that of the suction port size.
Is the Check Valve, Tee, or Elbow Installed Too Close to the Pump Inlet?
- Use a straight section of pipe at the pump's suction port (between the pump and the first elbow, tee, or check valve) that is a minimum of ten times the pipe's diameter. Use 24 inches to be safe. Having an elbow, tee, check valve, or other disruption too close to the inlet of the pump can cause cavitation inside the pump.
Is the Suction Pipe Submerged Deep Enough?
- Make sure the end of the suction pipe is submerged far enough into the water.
Is the Suction Pipe Burried in Mud?
- Make sure the suction pipe is not too close to the bottom of the well, lake, or water source so that it cannot pick up mud, dirt, or other debris. Raise the level of the pipe by putting bags of concrete on the floor of the water source so the pipe can rest on top without getting clogged.
Is the Suction Pipe Frozen?
- Make sure suction pipe is not frozen due to exposure to cold. Bury the pipes below frost line for permanent solution.
Symptom 3: Jet Pump Runs for a Short Time, Delivers Water, but Shuts Off Again
If your jet pump is running for a short amount of time, delivering water, but shutting off again, there are a few possible causes:
- The voltage is too low.
- The circuit breaker has tripped or a fuse has blown.
- The pressure switch is out of adjustment.
Is the Voltage Too Low?
- Measure the motor's voltage while it is trying to run. Comapare to the base voltage of what is supposed to go to the motor. If the voltage at the motor is more than 5% lower than the base voltage, check for loose connections or wire that is too light in gauge for the horsepower and length of wire.
Has the Circuit Breaker Blown?
- Inspect the pump for a jammed impeller or other damage. Clear the blockage if possible so the impeller can rotate freely.
- Ensure that the wire that runs from the breaker or fuse box to the pump is of a heavy enough gauge. Replace as needed.
- Make sure the power wires are not touching or grounded where they connect into the motor.
- Restrict the pump's output to keep the pump within its designed performance range. Since the motor on a jet pump is free flowing, it will draw more amps when it is allowed to flow lots of water with no back-pressure.
Does the Pressure Switch Need Adjusting?
- · Adjust the pressure switch on your jet pump properly, or replace the switch if found to be faulty.