Burner Calculators
Burner Air Register Opening Calculator
Calculate actual air flow from register opening percentage using the standard sine-curve damper flow characteristic.
Burner Capacity Calculator
Calculate maximum burner heat output capacity from fuel flow rate and heating value.
Burner Combustion Air Fan Power Calculator
Calculate combustion air fan shaft power from air flow, system pressure rise, and fan efficiency.
Burner Combustion Air Preheat Savings Calculator
Estimate fuel savings percentage from combustion air preheat using a simplified heat balance against adiabatic flame temperature.
Burner Combustion Chamber Heat Release Density Calculator
Calculate volumetric heat release rate (kW/m3) from burner heat input and combustion chamber volume.
Burner Fan Total Static Pressure Calculator
Calculate total static pressure a combustion air fan must overcome by summing burner pressure drop and duct system losses.
Burner Firing Rate Calculator
Calculate a burner's current firing rate as a percentage of its maximum fuel flow.
Burner Flame Failure Response Time Calculator
Calculate total flame failure safety response time by combining flame detection delay and fuel valve closure time.
Burner Fuel Changeover Pressure Calculator
Calculate the equivalent supply pressure needed when converting a burner between two different fuel gases through a fixed orifice.
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 Gas Train Pipe Sizing Calculator
Calculate minimum gas train pipe diameter from flow rate and maximum allowable gas velocity.
Burner Ignition Spark Energy Calculator
Calculate ignition spark energy from capacitance and discharge voltage using the standard capacitor discharge energy formula.
Burner Nozzle Exit Velocity Calculator
Calculate burner nozzle exit velocity from volumetric flow rate and nozzle cross-sectional area using the continuity equation.
Burner Orifice Size Calculator
Calculate the required burner orifice diameter from target flow rate, pressure drop, and fluid density.
Burner Pilot Sizing Calculator
Calculate pilot flame BTU/hr sizing as a percentage of main burner capacity.
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 Standby Heat Loss Calculator
Calculate ongoing heat loss from a hot burner enclosure during standby off-cycles using U-value, surface area, and temperature difference.
Burner Turndown Ratio Calculator
Calculate a burner's turndown ratio from its maximum and minimum stable firing rates.
Burner Warm-Up Time Calculator
Estimate burner cold-start warm-up time from refractory mass, specific heat, temperature rise, and heat input rate.
Sizing the Heart of Every Combustion System
A burner has to deliver the right fuel and air flow across a wide range of firing rates — too small and it cannot meet peak demand, too large and it runs inefficiently at partial load. These seven calculators cover burner sizing, pressure, and turndown math.
How to Approach Sizing a Burner, Step by Step
- Find peak heat demand. Use the Burner Capacity Calculator against your system's maximum required output, not the average.
- Check the turndown range. The Burner Turndown Ratio Calculator shows how low the burner can throttle while still burning cleanly — a 10:1 ratio means it can run as low as 10% of rated capacity.
- Confirm fuel pressure and orifice size match. The Burner Fuel Pressure Calculator and Burner Orifice Size Calculator need to agree with each other for the target flow rate.
- Check typical, not just peak, load against the turndown range. A burner spending most of its life at the bottom of its turndown range loses efficiency — often 5-10 percentage points lower than running closer to its middle range — from poorer air-fuel mixing at low flow.
Popular Burner Calculators
- Burner Sizing Calculator — combines fuel type and heat demand into a recommended burner capacity.
- Burner Pressure Drop Calculator — estimates pressure loss across the burner at a given flow rate.
A burner oversized for typical demand spends more time at the inefficient bottom of its turndown range than a correctly sized one would — matching size to actual load, not just peak, is often the bigger efficiency lever than the burner model itself.
Related: Boiler & Furnace Calculators for full system sizing, Air & Fuel Calculators for the ratio math underneath.