1. What is Heat Pump Sizing?

Heat pump sizing calculates the appropriate capacity (in BTU or kW) needed to efficiently heat or cool a space based on room size, insulation quality, and climate factors. Proper sizing is crucial for energy efficiency and comfort in New Zealand homes.

2. How Does the Calculator Work?

The calculator uses the standard heat pump sizing formula:

Where:

• \( Area \) — Room area in square feet
• \( Factor \) — BTU per sq ft (20-40 depending on climate and room type)
• \( Insulation\ Adjustment \) — Multiplier based on insulation quality (0.8-1.2)

Explanation: The calculation accounts for room size, typical heat loss/gain (factor), and insulation quality to determine the optimal heat pump capacity.

3. Importance of Correct Sizing

Details: Properly sized heat pumps operate more efficiently, last longer, and provide better comfort. Undersized units struggle to maintain temperature, while oversized units short-cycle, reducing efficiency and lifespan.

4. Using the Calculator

Tips:

• Measure your room area accurately
• Choose higher factors (35-40) for living areas, lower (20-25) for bedrooms
• Select insulation level based on your home's insulation quality
• For whole-house systems, calculate each room separately then sum

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between BTU and kW?
A: BTU (British Thermal Unit) is the traditional measure, while kW (kilowatt) is the metric standard. 1 kW ≈ 3412 BTU.

Q2: How do I measure my room area?
A: Multiply length by width in feet. For irregular rooms, divide into rectangles and sum the areas.

Q3: What factor should I use for my region?
A: Use 30-40 for colder South Island areas, 20-30 for warmer North Island regions.

Q4: How do I assess my insulation?
A: Good insulation = double glazing, insulated walls/ceilings. Poor = single glazing, uninsulated.

Q5: Should I round up the calculated size?
A: Choose the nearest standard size (typically in 0.5kW increments), but avoid oversizing by more than 20%.