Foodservice Equipment Reports

FER FOCUS: Building A Better Combi

Ever notice how QSRs provide value to their customers? Take some of their best-selling menu items, put them together in combinations that make a meal and sell the combinations at a good price. 

Decades ago, some geniuses in Europe at companies like Burger Eisenwerke AG (later acquired by Electrolux) and Rational got the brilliant idea to create a mash-up of a convection oven and steamer. The resulting “combi” oven could cook more types of food faster with less shrinkage and better finished quality than a convection oven or steamer on its own.

Pressed for space, European chefs quickly adopted combi ovens as one of their favorite pieces of foodservice equipment. Like a Swiss Army knife, a combi oven offers multiple functions in a single box. With more space to spread out in American kitchens, combi ovens have been slower to catch on because of their relatively high price and more complex operation compared with dedicated equipment. 

All of that is changing for a number of reasons. First, real estate now is more expensive, so operators feel pressure to squeeze more production capacity into smaller spaces. Second, the higher price of a combi doesn’t look quite as daunting when one unit can do the work of a steamer and convection oven, a proofer and possibly a fryer or two, among other pieces of equipment.

We also told you a few years ago about the new ASTM F2861-10 test method that makes it possible to compare the performance and efficiency of the wide range of combi ovens available (check out for a comparison chart from 2013). The standardized test method also recently led the U.S. Department of Energy to include combi ovens as a category in its Energy Star program. 

The combination (pun intended) of all of the above has led a number of manufacturers not only to get busy testing their models, but also designing and engineering what might be considered fourth generation ovens. A baker’s dozen already are listed on the Energy Star website, Between now and the National Restaurant Association Show in May, you can expect manufacturers to introduce a host of new products. And the multi-functionality of the latest combis resembles not so much a Swiss Army knife as a smart phone. The range of sizes has increased as well, with half-sizes and minis commonly available.

Touchy Feely 

Probably the biggest operator complaint, and barrier to adoption in the U.S., has been the difficulty of learning how to operate a combi. While European chefs have had a lot of experience cooking with them, to cooks and kitchen employees used to simply turning equipment on, operating a combi looks like rocket science.

The last generation of ovens came with digital controls and preprogrammed cooking cycles to help alleviate the pain. But complaints kept coming. So, the latest generation sport capacitive touch screens much like those on tablets and smart phones instead of the resistive touch pads on older models. 

These touch screens also access much more powerful computer chips and software, expanding a combi’s capability and ease of use. Memory capacity, for example, typically has doubled; one maker’s units now hold 500 recipes, up from 200. And as if onboard memory isn’t enough, several new models now connect wirelessly to the Internet so you can access recipes from a corporate server or even trade recipes and combi cooking techniques with other chefs.

More importantly, and what’s likely to be a buzz at the NRA Show, is a much improved user interface on many of these models. Touch-screen controls offer users instruction in multiple languages, use icons instead of words in most cases and provide video instruction if users need it. 

Best of all, manufacturers are making the controls and operation of these ovens much more intuitive. Most of these interfaces operate much like apps on a smart phone, something with which today’s kitchen employees are usually very familiar. And, says one maker, this new approach means oven operating systems can be upgraded like phones or tablets, so the technology won’t become outdated as quickly.

Speed And Precision 

Versatility—cooking in different ways with one piece of equipment—is one reason many operators buy combi ovens. Speed is another. Combi ovens typically cook most menu items 30%-50% faster than conventional equipment. New equipment coming to market promises to be even faster and more precise, increasing your kitchen’s productivity and improving product consistency.

Manufacturers say their new models are able to achieve this feat in a couple of different ways. One is through more precise control of humidity in the cabinet. New models can maintain humidity levels to within 1% or 2% on a constant basis, and, rather than guessing, you can set a specific humidity level by percentage. That means a more precise cook cycle, less product shrinkage and greater consistency. 

Some models also maintain better control over energy usage, which means more consistent cabinet temperatures and faster cook times. Rather than firing burners or turning on electric heating elements when cabinet temperature falls below a certain point—meaning the oven is either on or off—these models automatically adjust the flame or heating element up or down incrementally depending on demand, just as you would on a range or stovetop. One maker’s new models have a turbo-boost power mode that speeds cooking by 20%.

Better management of how steam is produced also makes cook cycles faster and more consistent. Older models, whether with or without a boiler, often generate lots of steam that is then “injected” into the cabinet by opening a valve. New models generate only as much steam as the cook cycle you program calls for. 

Improved air circulation in many models also speeds cooking and boosts consistency. Several makers have switched to fans with up to nine speeds (vs. old three-speed fans) that also are reversible. The combination of energy-efficient, reversing fans with a greater number of speeds circulates air and steam more effectively, saves energy and ensures faster and more consistent heat transfer.

More Miles Per Gallon 

Power and precision are great for those who can afford the gas-guzzling characteristics of an expensive sports car. But new combi ovens are practically teetotalers compared with early generations, sipping energy and water like an economy car, which should be good news to most of you.

Different models save water and energy in different ways, and often the same engineering that makes an oven cook faster and/or more consistently is one that also saves water and/or energy. 

Those models that turn a gas burner or heating element up or down instead of on or off when responding to temperature changes use energy more efficiently. One manufacturer has redesigned the burners in its gas combis to sip gas more economically. Another has redesigned how steam is produced in its ovens, combining a smaller boiler with steam injection. About the size of a 1-lb. coffee can, the small boiler essentially acts like a traditional water heater, holding water hot until the steam-injection heater, acting like a booster, heats the water to steam temperature. The unit saves both water and energy.

Self-Cleaning Changes 

To conserve energy and water (and meet new Energy Star specs), many manufacturers have focused on redesigning the self-cleaning systems on their ovens. One maker has halved the water used in the cleaning cycle. A more effective solid detergent fits into a specially designed drawer.

Another has added flexibility to its self-cleaning feature, allowing operators to increase the number of wash cycles (up to five) to correspond with how dirty the oven actually is. Designed much like an undercounter dishmachine, the oven’s wash cycles also now use recirculated wash water, so less water goes down the drain. 

A five-speed fan and more efficient wash cycle have helped another maker increase the efficiency of its self-cleaning system by 35%.

Many combi models also now feature an auto deliming feature that senses when the boiler and/or injection-steam heating elements need cleaning. Keeping these elements free of mineral buildup increases their efficiency and service life. One maker says its system is so effective, you only have to use distilled vinegar to delime the unit instead of a harsh deliming chemical. 

One oven line even has an app on its touch-screen dashboard that shows how much energy and water you’ll use with each cook cycle.

Sizing Them Up 

Several manufacturers are making other improvements as well. One designed a new grease-collection system for its ovens and improved its ventless hood, increasing the number and types of operations (and locations) that can use it. Several have redesigned service access to their ovens, making them easier to repair in the event they go down, and virtually all new models have been designed for greater reliability.

Several makers have added a feature that turns your combi into a cold or hot smoker as well, and at least one allows you to add your own spice mix to whatever you’re cooking. The smoker unit vaporizes the spices and injects the vapor into the oven. 

The upshot of many of these design changes on most new models has been to make the ovens more compact, putting the same capacity in a smaller footprint. With real estate and construction costs climbing, that should be good news to many of you.

And lest you think that all of these new features and fancy technology will just drive up the prices of new models, a few manufacturers are coming out with new value lines that offer simple operation and fewer bells and whistles. These ovens are so affordable that even budget-conscious operations like schools are snapping them up in droves.




The following is a list of major manufacturers of combi ovens. Several have new models coming soon but did not have materials ready in time for this issue’s Gallery. 

(new combi available now) 

BKI Worldwide/Standex
(new combi available now) 

Blodgett Corp./Middleby

Convotherm USA/Manitowoc Foodservice
(new combi in May) 

(new combi available now) 

Groen/Unified Brands

Henny Penny Corp.
(new combi in May) 

Hobart Corp.
(new combi this month) 

Lang Mfg. Co./Middleby
(new combi this month) 

Piper Products Inc.
(new combi in May) 

Rational USA

Seco Select/Affinis


Vulcan/ITW FEG
(new combi this month)

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