Boiler Sizing Calculator
Determining the correct size for a domestic hot water (DHW) tank and its heating element is critical for ensuring user comfort while maintaining energy efficiency. Our Boiler Sizing Calculator provides precise estimates for tank volume, daily energy demand, and necessary heater power based on the number of occupants and building type.
Boiler Sizing
Tank Volume (L)
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Daily Energy Demand
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Heater Power
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Note: Calculation based on TS 11268 guidelines.
How to Use the Boiler Sizing Calculator
- Enter Occupancy: Input the total number of people who will be using the hot water system in the building.
- Select Building Type: Choose the appropriate building category (Apartment, Hotel, Hospital, or Sports Facility). This determines the specific daily hot water demand profile per person.
- Choose Energy Source: Select between Electric (Standard storage) or Gas (Fast recovery). Gas systems typically require smaller storage tanks because they heat water faster.
- Adjust Temperatures: The default design conditions are 60°C for hot water and 10°C for cold mains water. You can adjust these based on your local climate and system requirements.
- Review Results: The calculator instantly provides the recommended Tank Volume (L), the Daily Energy Demand (kWh/day), and the Heater Power (kW) required to meet the load.
Note: This calculation is based on TS 11268 guidelines and standard thermal engineering principles.
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