There are many ways in which a well pump can malfunction, and many reasons for each malfunction to occur. Whether your well pump motor is not starting, will not stop starting, or never stops at all, there are several avenues you can explore to see what might be wrong. Troubleshooting a well pump problem generally involves inspecting the many parts of the pump for signs of damage or improper functioning. Often a diagnosis is made through the process of elimination. Depending on your knowledge of plumbing and electrical systems, many of the repairs can be done without professional advice.
When the Motor does Not Start
Your well pump motor may not start for a number of reasons. Some are simple to fix and some require additional labor and expertise: Check the fuses and the circuit breaker box. If a circuit breaker has tripped simply flip the switch. Look for any dirty, loose or corroded fuses that may require replacing.
Inspect the wiring, cabling and pressure switch. Similar to the fuses, look for corrosion or loose connections that may need to be replaced. Check the pressure switch by testing the voltage at the contact points. If there is little or no voltage first try to clean the contact points. If that fails try replacing the pressure switch. Measure the voltage at the line terminals. Use a voltage meter to see If the voltage is at plus or minus ten percent of the rated voltage. If the voltage is reading incorrectly you will need to contact the power company.
When the Motor Starts too Often
Check the pressure switch. If the pressure switch setting is incorrect simply reset. If there are any noticeable defects it will need to be replaced. Inspect the check valve. If the check valve is stuck open it will not hold the proper pressure and continue to start. If this is the case it will require replacing. Check the air charge. A faulty air charge can lead to a tank that is waterlogged and will need to be replaced. Inspect the pipes. Take a look at the pipes connected to the well pump to see if you find any obvious leaks that require pipe replacing or repairing.
When the Motor Won't Stop Running
Check the pressure switch. See if adjusting the pressure switch stops the motor and solves the problem. Otherwise try and clean the contacts. If this does not work you may need to replace the pressure switch. Look for loose or broken well pump parts. Inspect the pump for loose couplings or a broken motor shaft, If you see any obvious damage it will need to be repaired or replaced. Inspect the check valve. If the check valve is in the closed position it will stop the motor. Simply adjust the valve. Check the pump screen. If it is blocked or clogged by dirt or debris remove it by wiping whatever is clogging it away.
Signs of a Well-Worn Pump
The signs that a well pump has lived out its lifespan are similar to what happens when there is a low leak or when the well's water level is too low. You can diagnose a worn pump via the process of elimination. Rule out a leak by inspecting the pipes. Next lower the pressure switch. If the pump shuts off then worn parts may be to blame and the parts and/or the entire well pump may likely need replacement.
It is clear that certain aspects of well pump troubleshooting require some knowledge and comfort working with electrical and plumbing systems. When in doubt, choose safety by calling a licensed repair person. Don't try to make electrical or plumbing repairs if you are not qualified.