To calculate combustion air, multiply the volume of the space (V) by the area of the opening (A), then multiply by the temperature and pressure factors (TP), the required air per unit of fuel (R), and the safety factor (Z). This gives you the amount of air needed for proper combustion.

A **Combustion Air Calculator** is an essential tool used to determine the amount of air required to properly combust fuel in appliances such as furnaces, boilers, and water heaters. Proper combustion requires the right balance of air to ensure efficiency and safety.

**Formula:**

**CA = V × A × TP × R × Z**

Symbol | Meaning |
---|---|

CA | Combustion Air (amount required) |

V | Volume of the space |

A | Area of the air opening |

TP | Temperature and pressure factors |

R | Required air per unit of fuel (e.g., BTU) |

Z | Safety factor |

### Solved Calculation:

**Example 1:**

Calculation |
Instructions |
---|---|

Given: V = 500 ft³, A = 1.5 ft², TP = 1.1, R = 50 BTU, Z = 1.2 |
Start with the known variables. |

CA = 500 × 1.5 × 1.1 × 50 × 1.2 | Multiply volume, area, TP factor, air requirement, and safety factor. |

CA = 49,500 | The total combustion air required is 49,500 ft³. |

**Example 2:**

Calculation |
Instructions |
---|---|

Given: V = 800 ft³, A = 2.0 ft², TP = 1.05, R = 60 BTU, Z = 1.15 |
Start with the known variables. |

CA = 800 × 2.0 × 1.05 × 60 × 1.15 | Multiply volume, area, TP factor, air requirement, and safety factor. |

CA = 115,920 | The total combustion air required is 115,920 ft³. |

### What is Combustion Air Calculator ?

A **Combustion Air Calculator** is a crucial for ensuring proper ventilation in heating systems, such as furnaces and boilers. It helps users determine the amount of fresh air needed for efficient combustion.

Typically, the calculation involves understanding the **combustion air requirements** for the fuel being used, such as propane or natural gas.

For instance, a common guideline is that you need **50 cubic feet of air per 1,000 BTU** of heating output. This ensures that the burner receives enough air to operate efficiently and safely, preventing issues like backdraft in gas furnaces.

To effectively use this calculator, start by entering the BTU rating of your appliance. This will help you understand **how much combustion air is required for a 100,000 BTU burner** or any other size.

You can also explore options like the **combustion air calculator app** or Excel templates for more detailed calculations. Understanding the importance of **furnace room ventilation** and adhering to local codes, such as the **furnace fresh air intake code**, is essential for safety. Proper installation of combustion air vents, often referred to as **fan in a can**, can significantly improve air quality and system performance.