Reading Kitchen Burner Ratings by the Minute Instead of the Hour
Every piece of gas cooking equipment carries an input rating in BTU per hour on its plate, and that is the figure a kitchen schedule is built from. Once the pipework, the meter and the regulator come into it, the useful view is what the burners swallow in a minute — the rate that a manifold has to sustain while a whole line fires at once during service.
What the Plate Rating Actually Tells You
It is input, not delivered heat
Wok ranges dominate a schedule
Meters are quoted per hour, but sized for peaks
Same rating, different gas
Building a Kitchen's Connected Load Line by Line
The schedule comes off the equipment supplier's cut sheets one appliance at a time; the conversion is what makes the totals comparable with meter and regulator data.
Type in the nameplate input
Enter the appliance's BTU/h figure — 54,000 for a convection oven, 232,000 for a range with its oven — and the per-minute rate appears as you type. A comma works as the decimal mark and spaces in the number are ignored.
Total the line, then convert once
Add the appliances sharing a branch and run the sum through in one go. The eight-item kitchen in the table below comes to 987,000 BTU/h, which is 16,450 BTU/min, or close to 16 cubic feet of natural gas every minute.
Reverse it for specs written per minute
Burner and pilot data occasionally arrives in BTU/min. The swap button (↔) runs BTU/min → BTU/h so a supplier's figure can go into the schedule in the same units as everything else — multiply by 60 if you are checking it by hand.
Drop the value into the schedule
The copy button puts the bare number on the clipboard with no unit and no spaces, which is what a spreadsheet column of appliance loads expects. Ctrl + C in a field does the same thing.
Firing Rates and Connection Sizes for Commercial Cooking Equipment
Representative input ratings for a mid-sized restaurant line. Connection sizes are the manufacturer's inlet on the appliance itself, which is not the same thing as the branch that feeds it.
| Appliance | Input (BTU/h) | Firing rate (BTU/min) | Typical inlet |
|---|---|---|---|
| Salamander broiler | 36,000 | 600 | 1/2 in |
| Full-size convection oven | 54,000 | 900 | 3/4 in |
| 36 in griddle | 90,000 | 1,500 | 3/4 in |
| Boilerless steamer | 100,000 | 1,667 | 3/4 in |
| 40 lb fryer | 105,000 | 1,750 | 3/4 in |
| 36 in char-broiler | 120,000 | 2,000 | 3/4 in |
| Six-burner range with oven | 232,000 | 3,867 | 3/4 in |
| Two-burner wok range | 250,000 | 4,167 | 1 to 1-1/4 in |
Added together, that line is 987,000 BTU/h — 16,450 BTU/min, or roughly 958 cubic feet of natural gas an hour. Two appliances out of eight account for nearly half of it, which is the usual shape of a kitchen schedule: the heavy cooking suite decides the service size and the small equipment barely moves the total.
Working Through an Equipment List
Both boxes live while you total the line
Type into either field and the other keeps pace, so you can run down a page of cut sheets entering one appliance after another with nothing to reset.
One tap back to plate units
The swap button flips the pair, which is what you want when a burner is specified per minute and the rest of the schedule is written per hour.
kW-rated imported equipment fits too
Searchable dropdowns on both sides reach kW, BTU/s and every other power unit, so a European combi oven quoted in kilowatts lands in the same schedule as the domestic kit.
Clean figures for the load sheet
Results carry up to eight decimals with thousands spaced apart, and copying hands over the number alone, without the unit tagging along into your spreadsheet.
Kitchen Gas Load Questions
Should the gas line be sized for every appliance rating added together?
As a default, yes — gas codes size pipe on the total connected load, on the assumption that everything can fire at once. Real kitchens rarely do: measured demand often sits somewhere between 60 and 80 % of the schedule. Some authorities will accept a diversity factor for large installations if it is backed by documented usage and the appliance manufacturer's data, but that is a case you make to the inspector, not something to assume on the drawing.
Why do regulator and manifold specifications talk about flow per minute?
Because the failure is momentary. A regulator has to hold outlet pressure through the step change when a wok range and a fryer both light within a few seconds, and that behaviour is described by flow per minute, not by an hourly average. Converting the schedule to BTU/min — 16,450 for the kitchen above, near 16 cubic feet of natural gas a minute — puts the load in the same terms as the regulator's response and the meter's slam capacity.
Is an appliance's input rating the same on propane as on natural gas?
The nominal BTU/h stays the same, but the appliance does not. Propane packs about two and a half times the energy per cubic foot and runs at a higher manifold pressure, so it needs smaller orifices and a different regulator spring — the manufacturer's conversion kit, fitted by someone qualified to do it. Run an appliance on the wrong gas with the wrong orifices and you get either a starved burner or a dangerously over-fired one.
How much input does altitude take off a burner?
Thinner air means less oxygen per cubic foot, so the input has to come down to keep combustion clean. Equipment is normally certified as-supplied up to about 2,000 ft; above that the traditional US rule is a 4 % reduction per additional 1,000 ft, achieved with a high-altitude orifice set from the manufacturer. Always take the appliance maker's derate table over the rule of thumb, and remember the derated input is the number that should go into the schedule.
How does the connected load feed into hood and make-up air sizing?
Hood exhaust is set by duty and hood length rather than BTU directly — roughly 200 CFM per linear foot for light duty such as ovens and steamers, 300 for ranges, fryers and griddles, and 400 or more for char-broilers and wok ranges. Make-up air then replaces 80 to 90 % of what is exhausted. The gas load matters separately for combustion air: the standard method allows around 1 square inch of opening per 4,000 BTU/h across two openings to outdoors, which for a 987,000 BTU/h kitchen is roughly 247 square inches each.
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