1. What is Water Pump Power Calculation?

Definition: This calculator determines the required horsepower for a water pump based on flow rate, total head, and pump efficiency.

Purpose: It helps engineers, plumbers, and irrigation specialists properly size pumps for various applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( HP \) — Horsepower required
• \( Q \) — Flow rate (gallons per minute)
• \( H \) — Total head (feet)
• \( \eta \) — Pump efficiency (0-1)
• 8.34 — Weight of water (lbs/gallon)
• 3960 — Conversion factor (ft-lb/min to HP)

Explanation: The formula calculates the power needed to move water against gravity and system resistance.

3. Importance of Pump Power Calculation

Details: Proper pump sizing ensures efficient operation, prevents energy waste, and avoids premature pump failure.

4. Using the Calculator

Tips: Enter flow rate in GPM, total head in feet, and pump efficiency (default 0.85 for 85%). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is total head?
A: Total head is the vertical distance plus friction losses in the piping system (measured in feet).

Q2: What's a typical pump efficiency?
A: Most pumps operate at 50-85% efficiency. High-quality pumps may reach 90%.

Q3: Why 8.34 in the formula?
A: This represents the weight of one gallon of water in pounds at standard conditions.

Q4: Should I round up the HP result?
A: Yes, typically select the next available pump size above your calculated value.

Q5: Does this account for motor efficiency?
A: No, this calculates hydraulic horsepower. For brake horsepower, divide by motor efficiency.