What is a well tank?A well tank is just one part of a private well water system. If you're connected to city water, you don't have a well tank. A well tank is usually found in your basement. Sometimes, it's in a crawl space or utility room. It's shaped like a cylinder and is blue or gray. The job of the well tank is to store the water that your well pump produces.
It's also known as a holding tank, water tank, or pressure tank. There's a bladder inside the tank that's surrounded by pressurized air. The well pump will pump water into the system until it senses that the bladder has contracted enough. How does the well pump sense this happening? A pressure switch is the communicator between the well tank and well pump.
What is a pressure switch?The well pump shuts off when the pressure switch senses the optimal pressure has been reached in the tank. The well tank is now full of water and pressure, ready to be used. When you jump in the shower and turn it on, that nice blast of water is a result of the pressure that the well tank built up. The pressure decreases bit by bit, the longer you're enjoying your shower. The pressure switch will sense once the pressure decreases too much, and switches on the power to the well pump. This can also be described as the switch "calling for water." You'll hear the pump kick on which will pump water into the home and into the well tank until the optimal pressure is reached. The pressure switch will sense once the correct pressure is re-established inside the well tank and signal the well pump to turn off. The process will repeat itself over and over, each time you use the water.
What causes well tank failure?There are a few reasons that a well tank fails. The bladder can weaken over time. The tank itself can corrode and leak due to old age or poor water quality. Another cause is when the pressure switch fails.
A Columbia CT customer called us because her basement was flooding. She could tell the water was pouring in from somewhere but was unable to pinpoint the source. One of our plumber technicians was quickly dispatched. He was able to find the issue after a short diagnostic assessment. The well tank pressure switch was burned out. Because it couldn't send the message to the well pump to stop pumping water, the well pump continued to deliver water into the home. The water was pouring out of the safety relief valve. This caused the basement to flood. Our plumber technician was able to replace the pressure switch and the safety relief valve so that water could be restored to the home. The well tank was not damaged and did not need to be replaced.
This is what the burned out pressure switch looked like: