Water Well Pumps, Pitless Adapters, and Pressure Tanks Explained

If you live in a home that receives water from a water well, you have a complete water system that is responsible delivering the water to your home. A typical home water system consists of several components including a pump, a pitless adapter or unit, a pressurized storage tank and control devices that allow the system to run automatically.


The Components Of A Water Well System

Let’s examine these components and their relationship within a typical water well system.



The well pump handles drawing or lifting the water from your well and directing it through your plumbing into your home. There are several factors that go into sizing the correct pump for your families needs including:
• Well diameter
• Water table level in the physical well
• The number of fixtures needing water
• The amount of water use
• Peak demand


The typical residential use pump can deliver about ten gallons per minute and is powered by a 1/2 – 3/4 amp motor. There are two common water well pumps used in most residential water wells. The most common is called a submersible pump. Submersibles are used in drilled wells and are lowered directly into the well and placed below the water level deep enough to ensure replenishment during down times. The second type, known as a jet pump, Jets pumps are used in smaller diameter or shallow wells and are often located above ground and connected to the water well via piping. An easy way to understand the difference is that submersible pumps push water up from the well, while jet pumps pull the water to the surface.



Years ago, wells were often completed in large pits dug below ground level. This prevented the pump and pipes from freezing during cold weather. Unfortunately, well pits were also accessible to surface run off contamination and often dangerous to pets and small children who could fall into the pit if the pit cover became compromised. Current regulations prohibit the construction of well pits. Luckily, the invention of the pitless adapter or pitless unit has made the practice of well pits obsolete.


Pitless adapters are a special fitting that attaches to the water well casing below ground about 6 or 7 feet and discharges water through a buried water service pipe. It is buried below the frost line to prevent freezing. The well casing extends above ground and is covered with a well seal, which allows access for service and protects the well from surface contaminants. Pitless units are more complex and replace the well casing between the frost line and surface.



Most home water systems include a storage tank called a pressure tank. Usually located in the basement of the home, certain types of pressure tanks may also be buried underground. The pressure tank serves three main functions in a home water system.


1. To store water and deliver water under pressure when the main pump is not running.
2. To store a reserve supply of water when the pump is running so that it has to start and stop less often reducing wear and prolonging pump life.
3. To provide a water reserve during times of peak use or higher than normal demand.


A pressure tank is aptly named as it holds the reserved water under pressure. As the water is pumped in, it compresses the air in the tank until it reaches a predetermined pressure of usually between 40 and 60 pounds PSI, which automatically shuts down the pump. When a faucet is opened, this pressure forces water through the pipes until it drops to another preset level (usually 20-40 PSI) which starts the pump and repeats the process. A pressure switch is used to regulate the starting and stopping pressure at preset levels so the system works automatically.


These three components make up your home’s water system. Regular annual inspections and maintenance can keep your water system running perfectly for many years. If you’ve been putting it off, contact your local well water specialist and schedule an inspection. Keep your system running in top condition and it will provide fresh, clean water for you and your family for years to come!


Contact Skillings & Sons for advice on well problems and water well service.