Furnace and AC Size Calculator

BTU Calculation Formulas:

\[ \text{Furnace BTU} = \text{Sq Ft} \times 30 \] \[ \text{AC BTU} = \text{Sq Ft} \times 25 \]

BTU Required:

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1. What is the Furnace and AC Size Calculator?

The Furnace and AC Size Calculator helps determine the appropriate BTU (British Thermal Unit) capacity needed for heating and cooling systems based on square footage. Proper sizing ensures optimal efficiency and comfort.

2. How Does the Calculator Work?

The calculator uses industry-standard formulas:

\[ \text{Furnace BTU} = \text{Sq Ft} \times 30 \] \[ \text{AC BTU} = \text{Sq Ft} \times 25 \]

Where:

\( \text{Sq Ft} \) — Total area in square feet
\( \text{Furnace BTU} \) — Heating capacity required (BTU per hour)
\( \text{AC BTU} \) — Cooling capacity required (BTU per hour)

Explanation: These formulas provide baseline estimates for standard residential applications, with furnaces typically requiring more BTU capacity than AC units for the same area.

3. Importance of Proper Sizing

Details: Correctly sized HVAC systems operate more efficiently, provide better comfort, have longer lifespans, and reduce energy costs. Oversized systems short-cycle, while undersized systems struggle to maintain temperature.

4. Using the Calculator

Tips: Enter the total square footage of the space to be conditioned. Select the system type (furnace, AC, or combined system). For combined systems, both heating and cooling requirements will be displayed.

5. Frequently Asked Questions (FAQ)

Q1: Why are furnace and AC BTU requirements different?
A: Heating typically requires more energy input than cooling for the same space due to larger temperature differentials and heat loss factors.

Q2: Are these calculations accurate for all situations?
A: These are general estimates. Actual requirements may vary based on insulation, climate, window placement, ceiling height, and other factors.

Q3: What if my space has unusual features?
A: For rooms with high ceilings, many windows, poor insulation, or unusual layouts, consult with an HVAC professional for precise calculations.

Q4: How does climate affect sizing?
A: Colder climates may require larger furnace capacity, while hotter climates may need larger AC units. These calculations assume moderate climate conditions.

Q5: Can I use this for commercial spaces?
A: This calculator is designed for residential applications. Commercial spaces have different load calculations and should be evaluated by professionals.