1. What is a Combi Boiler Sizing Calculator?

Definition: This calculator determines the appropriate size (power output) of a combi boiler based on the required heat output.

Purpose: It helps homeowners and heating professionals select the correctly sized combi boiler for efficient operation.

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 (BTU/h) to kilowatts (kW), which is the standard unit for boiler sizing.

3. Importance of Correct Boiler Sizing

Details: Proper boiler sizing ensures energy efficiency, adequate 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.

5. Frequently Asked Questions (FAQ)

Q1: What's the conversion factor 3412?
A: 3412 BTU/h equals 1 kW, which is the standard conversion between these units.

Q2: How do I determine my required heat output?
A: Calculate your building's heat loss or consult a heating professional for a heat load calculation.

Q3: What's a typical BTU requirement for a house?
A: Averages range from 30,000 BTU/h for small apartments to 150,000+ BTU/h for large homes.

Q4: Should I round up the boiler size?
A: It's common practice to round up to the nearest available boiler size for a safety margin.

Q5: Does this account for domestic hot water needs?
A: No, combi boilers must be sized for both space heating and hot water demand - consult a professional.