Burner Calculators
Burner Capacity Calculator
Calculate maximum burner heat output capacity from fuel flow rate and heating value.
Burner Firing Rate Calculator
Calculate a burner's current firing rate as a percentage of its maximum fuel flow.
Burner Fuel Pressure Calculator
Calculate the fuel supply pressure required to deliver a target flow rate through a burner's fuel train, using its flow coefficient (Cv).
Burner Orifice Size Calculator
Calculate the required burner orifice diameter from target flow rate, pressure drop, and fluid density.
Burner Pressure Drop Calculator
Estimate burner pressure drop at a new flow rate by scaling from a known reference flow and pressure drop.
Burner Sizing Calculator
Calculate recommended burner capacity from peak heat demand plus a safety margin.
Burner Turndown Ratio Calculator
Calculate a burner's turndown ratio from its maximum and minimum stable firing rates.
Sizing a Burner to Match the Actual Load
A burner sized purely on peak demand often runs most of its life far below that peak, which is exactly why turndown ratio — how far a burner can modulate down from maximum firing rate — matters as much as raw capacity. Seven calculators here cover burner capacity, sizing, firing rate, and the pressure and orifice math behind fuel delivery.
Popular Burner Calculators
Seven tools span capacity, modulation, and fuel delivery:
- Burner Capacity Calculator — calculates maximum heat output a burner can deliver from fuel flow and heating value.
- Burner Turndown Ratio Calculator — calculates the ratio between maximum and minimum stable firing rate.
- Burner Firing Rate Calculator — calculates the actual heat input rate at a given fuel flow.
- Burner Pressure Drop Calculator — estimates pressure loss across a burner at a given flow rate.
- Burner Orifice Size Calculator — sizes a fuel orifice to deliver a target flow rate at a given supply pressure.
Why Turndown Ratio Matters More Than Peak Capacity
A burner with a high maximum capacity but poor turndown has to cycle on and off to handle low-load periods, which wastes energy on purge cycles and creates more temperature swings than a burner that can simply modulate down smoothly — this is exactly why a 10:1 turndown burner is often preferred over a larger, higher-capacity burner with only 3:1 turndown for a load that spends most of its time well below peak. Matching turndown ratio to the actual load profile, not just peak demand, is one of the most common burner selection mistakes to avoid.
Frequently Asked Questions
What turndown ratio is considered good for a modern burner?
5:1 is common for standard burners, while 10:1 or higher is available for burners designed for highly variable loads, letting them modulate down to 10% of capacity or less without cycling off.
Explore More
Sizing the boiler this burner feeds? See the Boiler & Furnace Calculators, or check the air side of combustion in the Air & Fuel Calculators.