How To Choose Windmill Equipment

We have provided information below that can be used to determine the approximate size of windmill that is required for your application. It should be noted that a ground water professional should be contacted to insure that all factors have been considered before ordering a windmill such as sucker rod type, prevailing wind speeds, etc.

About Pumping Capacities

Capacities are approximate and based on the mill operating in winds as shown below. The short stroke increases pumping elevation one-third and reduces pumping capacities one-fourth.

In 12 MPH winds, capacity is reduced about 20%; in 10 MPH winds, about 38%. If prevailing winds are low, use of a cylinder smaller than shown will permit your mill to operate in lower winds.

Never use pipe smaller than the size specified for the cylinder. For deep wells, use ball valve or Marcy cylinders with ash rod, other type of floating pump rod or fiberglass rod.

General Guide

This is a general guide. Ask your American West Windmill distributor to assist you in choosing the equipment that best fulfill your specific pump requirements.

  • Figure average daily water consumption by using the following guidelines.
  • Divide average daily water consumption by 5 to arrive at equivalent hourly pumping capacity required from your mill. This is based on wind conditions permitting your mill to pump the equivalent of about 5 hours of rated capacity per day. Naturally, this varies by locality.
  • Choose the cylinder diameter that is closest to the equivalent hourly pumping capacity by using the Table of Capacities.
  • Figure the total pumping elecation from the water level in the well to the point of discharge.
  • Choose the size mill to operate the cylinder when pumping to the total elevation by using the Table of Capacities.
  • Choose a tower that will place the center of the wheel at least 15 feet above wind obstructions within a radius of 400 feet.
  • Choose cylinder with a stroke at least 2 inches longer than the pumping stroke of the mill.
  • Choose pump rod, pipe and other accessories to size recommended for the specific cylinder.