Frequently Asked Questions - Oven Technology

What are the major causes of poor burner operation?

While the obvious answers to this question involve improper burner adjustment, and poor burner maintenance (especially poor cleaning), an insufficient supply of combustion air is probably at least as responsible for poor burner operation.

Most bakers seem to forget that, while heat energy is released when they burn gas (or wood, oil, or coal), and that the fuel being used is important, combustion also requires air - and air in comparatively large quantities. More specifically, oxygen is required for combustion, but the air we breathe contains only about 20 percent oxygen and almost 80 percent non-useable nitrogen. As such, for every single cubic foot of natural gas that we burn we will require about ten cubic feet of air. (Other fuels require different quantities of air for full combustion).

While carbon dioxide and water are the two main products of combustion that are produced when sufficient combustion air is supplied, and while neither is especially harmful to humans, we will have unburned gas and carbon monoxide produced when there is insufficient combustion air. Both are highly harmful to humans.

There are a number of reasons why insufficient combustion air is being supplied, and these will include poor burner adjustment and maintenance. However, a factor all too frequently ignored is that our ovens are equipped with exhaust fans. In addition, most bakeries usually have ceiling or wall mounted exhaust fans to expel heat and perhaps some smoke. These fans are constantly pulling air out of the area in which they are located, and, in extreme cases so much air is being pulled out of the room and not replaced that there is no longer sufficient air for combustion.

In addition to installing exhaust fans to extract products of combustion, and heat from our oven room, it is equally important that a make-up air system be designed and installed so that fresh air is being brought into the area at the same rate it is being expelled.

Doors that open outwards and are hard to open, or winds whipping through an open doorway and into the oven room are good indications that we are expelling more air than we are bringing in, and it is highly probable that the burners are operating at far below their expected rate of efficiency.

For more information:
Telephone: 785-537-4750 or 800-633-5137
FAX: 785-537-1493
Email: bstrouts@aibonline.org