Depending on the size of your establishment and how you want to use a charbroiler, you have a choice between three types of commercial grill. The largest and most robust are free-standing floor models. This is the kind you'll likely choose if it will be a primary piece of equipment, one that you'll be using nonstop during business hours. Smaller countertop and drop-in models are available, mostly for lower-volume operations where the equipment will play a supporting role, like at a concession stand or pub.
The grates on a commercial charbroiler come in two basic types: steel and cast iron. The most rugged option is cast iron. This material will hold up under heavy use and has excellent heat retention properties, meaning it stays hot when cold foods are added, speeding up the cooking process. Care must be taken with a cast iron grate to keep it properly seasoned. This involves some extra steps, but if you follow the directions of the equipment manufacturer, it will create a nonstick surface that is well worth the effort.
Stainless steel is the most economical option and is also easier to clean, but doesn't have the nonstick properties that a well-seasoned cast iron grate has.
Welded grates are the most common and economical. Their rods are permanently welded to a frame, creating a rigid, durable grate. The downside to these is that the welds tend to become weak over time from the material heating and cooling, and the grate will need to be replaced if the welds begin to break. Floating grates are made with free-floating rods that aren't fully welded to their frame, allowing them to expand and contract freely as they are heated and cool, so they tend to stay strong and not wear out as quickly as welded grates
Another option is reversible grates, which have ridges on one side that are thicker than the ones on the other side, so you can flip them over to cook different types of food. Steak, for example, is best cooked on thicker ridges. Thick ridges help drain grease and provide good heat distribution for thicker products. More delicate items like fish are best cooked on thinner ridges that offer more support to thin cuts of meat and have less surface area, which reduces the likelihood your foods will stick. Sectional grates are composed of individual sections, so they can be adjusted and reversed for cooking multiple types of items at the same time.
Grate profile refers to the way that the grate sits on the unit – flat or slanted. Flat grates are what you want if you're mostly going to cook a single type of item, like if you specialize in burgers. Heat distribution is mostly uniform across a flat grate, and juices drip straight down onto the radiants or char rocks to become vaporized, creating the classic chargrilled aroma and flavor.
Slanted grates sit above the heat source at an angle, so the raised part of it is further away from the heat of the unit's burner. This arrangement will let you cook food on the higher portion at lower temperatures. This arrangement is useful for cooking steaks to different doneness levels on the same unit, with well-done steaks on the lower part and ones that need to be cooked rare on the higher portion. Food can also be placed on the higher portion to be held and kept warm until serving time as well. Slanted grates can help minimize the chance of flare ups and grease fires because when the grate is slanted, more of the grease will drip down the grates into the grease tray rather than onto the radiants or rocks.
For the best of both worlds, consider choosing a unit with adjustable grates. These can be arranged to sit flat or at an angle, so you can cook foods that do best on either. Often, a unit's grate will come in several individual pieces, so you can have flat and slanted surfaces at the same time.
Most of these units come in either natural gas or propane (LP). Natural gas usually comes through a network built by a utility. Propane is stored outside of your building in a holding tank and is refilled periodically by a gas company. Your decision will probably be determined by which resource you have access to or which one is more affordable.
Although their numbers are few, there are electric charbroilers available, and their main advantage is mobility. Since gas models need to be connected to a gas line, they are difficult to relocate if you need to move them. In most cases, you can simply unplug an electric unit and store it away or move it. This makes an electric model a great choice if you only want to use it occasionally or if you are going to use it for catering.
Heat in a commercial charbroiler is produced by a series of burners. Above the burners, heat is absorbed and spread out evenly with the help of metal radiants or pieces of stone. Metal radiants are made of either steel or cast iron. Cast iron radiants can be slow to heat up, but once they are hot, they retain their heat very well so they cook efficiently. Steel radiants are easier to keep clean, but don't retain heat quite as well.
Some electric models transfer heat through a sheathed element. In these, the element is encased in a tube that acts as a radiant, absorbing heat from the element inside and radiating it evenly towards the cooking surface.
The alternatives to metal radiants are ceramic briquettes and lava rocks. Lava rock will absorb and vaporize juices to achieve the classic smoky flavor, but they tend to cause flare ups that some operators might want to avoid. Ceramic briquettes are designed to radiate the heat and vaporize juices without the flare ups. These are each consumable items, so they must be replaced periodically, depending on how frequently you use your equipment and what kinds of foods you cook.