1. What is the Ducted Heat Pump HP Calculation?

The horsepower calculation for ducted heat pumps determines the required pump power based on flow rate, head pressure, fluid properties, and system efficiency. Proper sizing is critical for energy efficiency and system longevity.

2. How Does the Calculator Work?

The calculator uses the standard pump horsepower formula:

Where:

• \( Q \) — Flow rate in gallons per minute (GPM)
• \( H \) — Total head in feet (ft)
• \( SG \) — Specific gravity of fluid (1.0 for water)
• \( \eta \) — Pump efficiency (0.0-1.0)
• 3960 — Conversion factor (ft-lb/min per HP)

Explanation: The formula calculates the theoretical power required to move fluid against system resistance, adjusted for pump efficiency.

3. Importance of Proper Sizing

Details: Correct heat pump sizing ensures optimal performance, energy efficiency, and prevents issues like short cycling or inadequate heating/cooling capacity.

4. Using the Calculator

Tips: Enter flow rate in GPM, total head in feet, specific gravity (1.0 for water), and pump efficiency (typically 0.7-0.9 for most systems).

5. Frequently Asked Questions (FAQ)

Q1: What is total head pressure?
A: The sum of static head (vertical lift) and friction head (pipe resistance) in the system, measured in feet of fluid.

Q2: How do I determine my system's flow rate?
A: Flow rate depends on heat load and temperature difference. A typical residential system might be 3-5 GPM per ton of cooling.

Q3: What efficiency should I use?
A: Modern pumps range from 70-90% efficient. Check manufacturer specifications for your specific model.

Q4: Should I add a safety factor?
A: It's common to add 10-20% to the calculated HP to account for system variations and future needs.

Q5: How does this relate to tonnage?
A: 1 ton of cooling ≈ 12,000 BTU/hr. HP requirements vary based on system design and COP (Coefficient of Performance).