1. What is Heat Pump Sizing?

Heat pump sizing is the process of determining the appropriate capacity (in tons) of a heat pump needed to efficiently heat or cool a space based on the calculated heat loss and the system's Coefficient of Performance (COP).

2. How Does the Calculator Work?

The calculator uses the heat pump sizing equation:

Where:

• \( Heat\ Loss \) — Total heat loss of the building in BTU per hour
• \( COP \) — Coefficient of Performance (dimensionless efficiency ratio)
• 3412 — Conversion factor from BTU/h to tons (1 ton = 12,000 BTU/h)

Explanation: The equation calculates the required heat pump capacity by dividing the total heat loss by the product of COP and the conversion factor from BTU/h to tons.

3. Importance of Proper Sizing

Details: Proper heat pump sizing is crucial for energy efficiency, comfort, and system longevity. An undersized unit will struggle to maintain temperature, while an oversized unit will short-cycle, reducing efficiency and equipment life.

4. Using the Calculator

Tips: Enter the total heat loss in BTU/h and the COP value. Both values must be positive numbers. The calculator will provide the required heat pump size in tons.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical COP value for heat pumps?
A: Modern heat pumps typically have COP values between 2.5 and 4.0, with higher values indicating better efficiency.

Q2: How do I calculate heat loss for my home?
A: Heat loss calculations consider factors like insulation, window quality, building materials, and climate. Professional energy audits provide the most accurate results.

Q3: What does "tons" mean in heat pump sizing?
A: One ton of cooling capacity equals 12,000 BTU per hour, a standard measurement derived from the amount of heat needed to melt one ton of ice in 24 hours.

Q4: Why is the conversion factor 3412 instead of 12000?
A: The factor 3412 comes from dividing 12,000 BTU/h by 3.517 (approximately √12), reflecting the relationship between energy input and output in heat pump systems.

Q5: Should I size my heat pump for heating or cooling?
A: In most US climates, heat pumps should be sized for the heating load, as it's typically the greater requirement, though professional assessment is recommended.