Commercial Convection Ovens: Gas or Electric, Single or Double Deck

Buying a commercial convection oven comes down to two decisions: gas or electric, and single deck or double. Everything else — fan speed, rack count, door style — follows from those two. This guide works through both using real numbers, including what each option asks of your building before it can be switched on.

What a convection oven actually changes

A conventional oven heats by radiation and natural air movement. A convection oven adds a fan that pushes heated air across every rack, which flattens out the hot and cold spots and lets you load all five shelves without rotating pans halfway through. That is the whole point: not speed for its own sake, but the same result on the top rack as on the bottom one when you have ten trays to get out before service.

It also means you generally bake 25°F lower than a conventional recipe calls for, and check earlier than the stated time. Moving air transfers heat faster than still air does.

Gas or electric: run the arithmetic

This is where most buying guides wave their hands. Here is the actual comparison, using two ovens with the same cabinet and the same five racks.

At first glance the gas oven looks far more powerful — 54,000 BTU against the electric oven's 34,121. That comparison is misleading, because the two technologies do not deliver the same share of that input to the food.

The ENERGY STAR commercial oven specification (Version 3.0) sets its qualification thresholds for the two types at very different levels: a full-size gas convection oven must reach at least 49% cooking efficiency, while a full-size electric convection oven with five or more pans must reach at least 76%. Those are the benchmarks the industry uses, and the gap between them is the real story.

Two caveats worth stating plainly. Those efficiency figures are the ENERGY STAR qualification thresholds for each technology, not measured values for these specific ovens. And the gas oven's higher input does buy you something real: it recovers faster after a door opening, because there is more raw energy available to replace the heat that walked out. If your crew opens the door every ninety seconds during a rush, that matters.

What each one needs from your building

This is the part that derails installations, and it is worth settling before you order rather than on delivery day.

The gas oven still needs electricity

A gas convection oven is not a gas-only appliance. The FLM-COG runs its convection fan and controls on a 120V, single-phase connection, alongside the gas supply. If the spot you have in mind has a gas stub but no outlet, you need both before the oven will run. The unit is also listed for NG or LP, so confirm which fuel you are ordering it configured for — converting between the two is an orifice and pressure change, not a switch on the back.

The electric oven is hardwired, and it is a real circuit

The FLM-COE240-1 draws 10 kW at 240V single phase. That works out to about 42 amps (10,000 ÷ 240). Because an oven is a continuous load, the National Electrical Code requires the circuit and overcurrent device to be sized at 125% of that — roughly 52 amps — which in practice means a 60-amp circuit. It ships with no plug and must be hardwired by a licensed electrician.

Double that for the double-deck FLM-COE240-2, which is 10 kW per deck. Confirm on the spec sheet whether it lands on one feed or two before your electrician quotes the job.

Single deck or double deck

A double deck is not a bigger oven. It is two ovens stacked in the same 38-inch footprint — and on the gas models, two independent chambers.

• FLM-COG — single deck, 5 racks, 54,000 BTU
• FLM-COG-2 — double deck, 10 racks, 54,000 BTU per chamber (108,000 total), two independent chambers
• FLM-COE240-1 — single deck, 5 racks, 10 kW
• FLM-COE240-2 — double deck, 10 racks, 10 kW per deck

Independent chambers are the reason to go double rather than buying a second single later. You can hold rolls at 200°F in the bottom while the top runs 400°F for the dinner sheet pans, without either one waiting on the other. A single deck forces those two jobs into a queue.

The argument for two separate singles is redundancy — if one fails you still have an oven — but it costs you a second 38-inch footprint and, on the electric side, a second circuit. For most kitchens short on floor space, the double deck is the better trade.

What actually fits inside

Rack count tells you less than cavity size. The Flamaster 38-inch gas cabinet has a cooking area of 29 inches wide by 22 1/2 inches deep.

A full-size commercial sheet pan is 18 by 26 inches. Turned so its long edge runs across the width, it uses 26 of the 29 inches available and 18 of the 22 1/2 — so a full-size sheet pan fits, loaded sideways, five of them on the five racks. Half-size pans (13 by 18) go in two abreast. Worth checking the spec sheet for the electric model if pan size is the deciding factor, since it shares the same cabinet dimensions.

Footprint, weight and delivery

Both single-deck models measure 38 inches wide, 44 1/2 deep and 61.7 high, and weigh 550 pounds. Two numbers to check before you order:

• Door swing — these are independent doors with full-view windows, so measure the aisle in front, not just the alcove the oven sits in
• The path from the loading dock — 550 pounds does not go up a flight of stairs or through a 36-inch doorway without a plan

The hood question

Ask before you buy, not after. Ventilation requirements for cooking appliances are set by NFPA 96 and your local mechanical code, and whether a convection oven needs a Type I grease hood or can sit under a Type II condensate hood depends on what you cook in it and on your local authority having jurisdiction. A bakery running bread is a different conversation from a kitchen roasting fatty proteins. Call your AHJ or your hood contractor with the model number before the oven ships — it is a cheap phone call and an expensive surprise.

Putting it together

Start with the service you can actually get: gas line, or a 60-amp 240V circuit. Then decide deck count from how many jobs need to run at different temperatures at the same time. Cavity size and pan count settle themselves once those two are answered — every model here takes the same full-size sheet pan on five racks per deck.