1. What is a Well Pump Size Calculator?

Definition: This calculator determines the flow rate (GPM) of a well pump based on horsepower, efficiency, and total head.

Purpose: It helps select the properly sized pump for water wells, irrigation systems, and other water supply applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( HP \) — Pump horsepower
• \( \eta \) — Pump efficiency (0-1)
• \( H \) — Total dynamic head (feet)

Explanation: The formula calculates how much water a pump can move based on its power, efficiency, and the height it needs to lift the water.

3. Importance of Proper Pump Sizing

Details: Correct pump sizing ensures efficient operation, prevents overworking the pump, and matches water demand with supply capacity.

4. Using the Calculator

Tips: Enter the pump horsepower, efficiency (default 0.8 for 80%), and total head in feet. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is total dynamic head?
A: It's the total height the pump must lift water, including vertical lift and friction losses in pipes.

Q2: What's a typical pump efficiency?
A: Most submersible pumps operate at 70-85% efficiency (0.7-0.85).

Q3: How do I determine the required horsepower?
A: Use our Horsepower Calculator or consult pump performance curves for your specific application.

Q4: What flow rate do I need for my home?
A: Typical homes need 5-12 GPM, but this depends on the number of fixtures and simultaneous water use.

Q5: Does this account for pipe size and length?
A: No, these factors should be included in your total head calculation through friction loss calculations.