3 Common Causes Of Well Pump Failure

Posted on: 30 November 2021

If you own a home that relies on well water, you know your well pump is one of the most critical components of your freshwater system. For deep wells, you'll typically have a submersible pump that can sit anywhere from 50 feet below ground to several hundred feet below the surface. Replacing these deep pumps can often be costly and labor-intensive.

Because submersible pump replacement isn't a trivial job, it's helpful to know why your pump may fail and what you can do to extend its life. Although these machines are relatively straightforward, they can still fail in a variety of different ways. This article will outline three common causes of pump failure along with some tips to keep your pump running for as long as possible.

1. Seal Failures

Although your pump sits partially below water, the motor itself isn't waterproof. Instead, it relies on the casing to keep it dry and free of contamination. Of course, the housing for a pump isn't a single, seamless unit, which means that it relies on seals to prevent water from entering the housing. 

These seals can fail with age, causing the pump motor to wear out and seize. Unfortunately, there's not much you can do to avoid this situation. You can't easily remove a deep pump for routine maintenance, and these seals will typically fail as the pump nears the end of its lifespan. Once the motor seizes, you'll usually have no option except to replace the pump.

2. Dry Running

Running a pump with a dry well can produce several effects, most of which will quickly render the pump unusable. Short periods of dry running can wear out the seals, resulting in seal failure and ultimately causing the motor to seize up. Longer periods of dry running will cause the pump's motor to overheat, eventually destroying it and forcing you to replace your submersible pump.

If your well frequently runs dry, you may want to consider installing a dry well protection device. These cut-offs will prevent your pump from running when it's pulling nothing but air. Although these systems aren't fool-proof, they can help minimize the damage that a dry well can cause to your submersible pump.

3. Continuous Operation

Your pump operates on a relatively limited duty cycle. Instead of running continuously, it fills a pressure tank up to a high-pressure limit. The pump then shuts down until the tank's pressure falls below a minimum threshold. A faulty pressure switch or pressure tank, as well as leaky home plumbing, can cause your pump to run continuously or rapidly cycle, ultimately burning out the motor.

The best way to avoid this situation is to pay attention to your pump and address any issues that cause it to run more often than it should. If you notice your pump running when you aren't using water in your home, that's a good indication that you need to quickly address a potential issue before it leads to pump failure.