What Size Well Pump Should I Buy For My Water Well

 How To Size a Residential Well Pump

How To Size a Residential Well Pump

Determining the size of a home’s water well pump is largely based on the amount of water your family will need on a daily basis, but other factors, such as the capacity of the well and cost should also be considered.

The average American household needs 100 to 120 gallons per person per day, and a flow rate of about 6 to 12 gallons per minute. A quick way to estimate your home’s water needs is to count the number of water fixtures in your home, including showers, faucets, outdoor water spigots and water-using appliances like dishwashers and clothes washers. Calculate 1 gallon per minute for each appliance. That will show you the average gallons per minute needed for your home.

For example, a small home with one bathroom would have the following fixtures:
1 shower
1 toilet
1 bathroom sink
1 clothes washing machine
1 refrigerator ice maker
1 dishwasher
1 kitchen sink
1 outdoor spigot
= 8 gallons per minute
Types of pumps

Once you determine the required yield of your pump, consider the different types of well pumps. This is largely based on the depth and type of well servicing your home.
•    Jet pumps come in two varieties, shallow and deep, and are often combined with a pressure tank. The shallow well pumps use a single pipe to draw water from about 25 feet. Deep well jet pumps can draw water from more than 100 feet and use a two pipe system to draw water from the ground.
•    Centrifugal pumps consist of one pipe inserted into the water column at a shallow depth, usually no more than 25 feet. The pump then sucks water from the ground and into the home.
•    Submersible pumps are installed near the bottom of a home well and pumps water into the home only when needed. These are the most common type of well pump and can be used in deep wells.

Well Capacity

The general rule of well drilling is to never install a well pump that has a larger capacity than the well. If the home’s peak demand exceeds the rate of water available from the well, adjustments need to be made to the home water system to ensure adequate flow. This could be resolved by adding an additional water storage tank for use during peak times. You could also install a larger pressure tank. This added storage can also prolong the life of your pump because it does not need to run as often.

Water pressure

Adequate water pressure is needed to make sure the well meets the home’s needs. Water pressure refers to the force behind the water that pushes it through the home. The amount of water pressure for a home is usually between 40 and 60 pounds per square inch(psi).  

Low pressure can be the result of clogged or inadequate piping. Most pipes run from wells are less than an inch in diameter. If a well is hundreds of yards from the home it serves, the pipe will need to be large enough to allow more water flow. To see whether the pipes are clogged with sediment or corrosion, remove the aerator screen at the kitchen faucet. If bits of sediment or debris are visible, clogged pipes are likely to blame.

Purchasing a new well pump is an important investment that could affect your home’s water supply for up to 15 years. When making such a purchase you want to be sure you are buying the right pump for your home. We recommend calling a water system professional to help you make that choice. Skillings & Sons, Inc. has over 40 years experience installing new water wells and replacement well pumps. Contact us today and we can help you determine the size pump and cost of a new well pump for your residential or commercial property.