Causes of Premature Well Pump Failure - And What You Can Do About It

by Quin Trimble

A reliable supply of fresh water is vital for many of the functions of the modern home. Some uses for fresh water include bathing, cooking, laundry, flushing toilet, drinking water, watering landscaping, and many others. Most homes get their water from a municipal water district, or from a well. Homeowners who use a water well typically save money over those who use municipal water. However, for homes that rely on well water, it is critical that the well pump be reliable at all times.

As with any other mechanical device in your home, an electric powered submersible well pump can malfunction, and it can do so at the most inopportune time. This can be quite inconvenient and costly for the homeowner.

There are several things that can cause failure of a well pump, including the pump being undersized, voltage is too low, the pump is set too deep in the well, or the pump runs too often. It’s beyond the scope of this article to examine all potential problems, but let’s take a look at one: the pump motor runs too often.

It May Be the Pressure Switch

When the motor on a well pump starts and stops too often, the first place to look is at the pressure switch. It is common for the settings on the pressure switch to be incorrect. Just reset the switch and see if that solves the problem. If this doesn't solve the problem, the switch may be defective, and will need to be replaced.

Check the Check Valve

Another thing to look at is the check valve. When the check valve is left open, the well pump will continuously run and not turn off. As with the pressure switch, if the check valve is defective, you will need to replace it.

Is The Storage Tank Too Small?

Premature well pump failure may also occur when the storage tank is too small. Also known as a pressure tank or expansion tank, the primary purpose of this unit is to extend the life of the well pump. When the tank for your well pump is undersized, the motor will have to work harder, stopping and starting more frequently to fill the tank, which causes unneeded wear and tear. The constant on and off operation can cause the pump to fail before its time.

To prevent this, you may need to purchase a larger tank. A small tank will cause frequent short operations of the pump. Conversely, a larger tank will hold more water, thus requiring the pump to come on less frequently and extending its life. A general rule of thumb is to size the tank for one gallon of drawdown for each gallon of pump capacity. Sizing in this way will minimize the start and stops, and run the pump for the proper length of time.