1. What is a Residential Boiler Sizing Calculator?

Definition: This calculator estimates the required boiler power in kilowatts based on the heat output in BTU/h.

Purpose: It helps homeowners and HVAC professionals properly size residential boilers for efficient heating.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Boiler power (kilowatts)
• \( Q_{btu} \) — Heat output (BTU per hour)

Explanation: The formula converts British Thermal Units per hour to kilowatts using the conversion factor 3412 BTU/h = 1 kW.

3. Importance of Proper Boiler Sizing

Details: Correct boiler sizing ensures energy efficiency, proper heating capacity, and prevents short cycling or insufficient heating.

4. Using the Calculator

Tips: Enter the required heat output in BTU/h. The value must be > 0. The calculator will output the equivalent boiler power in kW.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine my home's heat output?
A: Perform a heat loss calculation considering square footage, insulation, windows, and climate.

Q2: What's the typical BTU requirement for a house?
A: Roughly 30-60 BTU per square foot, but this varies significantly based on insulation and climate.

Q3: Why convert to kW instead of using BTU?
A: Many modern boilers are rated in kW, and this provides a standardized measurement.

Q4: Should I round up the boiler size?
A: It's common practice to add 10-20% capacity to the calculated value for safety margin.

Q5: Does this account for hot water needs?
A: No, this calculates heating needs only. Add 3-5 kW if the boiler will also provide domestic hot water.