The most common form of commercial HVAC heating use in factories and warehouses is a direct fired system. A direct fired system can also be called a furnace. Chemical industries use these systems to supply heat for chemical reactions through a boiler. These systems provide heat through fuel combustion, electricity, or induction heating. Furnaces have many components including the burners, heat exchanger, ventilation, controls, and the blower. The burners initiate and sustain the flame and the heat exchanger uses negative pressure to draw in the flame. Combustion occurs in the heat exchanger and as the gas cools it is makes its way to the blower which sends the heated air through the ventilation. Exhaust gases exit the building through ventilation pipes.
A more complicated design and process are used for metal and chemical reactions within a factory. In the metal and chemical industries, a direct fired commercial HVAC system either heats a process or a reaction. The design chosen for a particular business depends on many factors. Considerations that are often used to choose a furnace are its purpose, type of fuel that is available, and how the combusted air will be introduced. While the design of a furnace can be quite different for individual industries, there are common features that exist in every direct-fired furnace.
Two components cause the fuel to burn in the furnace: air from the air blower and fuel in the burner. Basic sections of these systems include the radiant and convection’s sections. Direct fired industrial HVAC systems can have multiple burners that are located in cells. Burners may also be located on the floor, wall, or roof. Each cell has the function of heating a set of tubes. Tubes in the radiant section receive a majority of the heat and may be vertical or horizontal depending on the design. These tubes are either located on the wall itself or in cells. They are made out of carbon steel and easily maintain a consistent temperature. Fluid within the tubes is heated to a set temperature in the tubes. The convection section makes use of additional heat. A cylindrical flue gas stack is attached to the top of the heat transfer chambers and collects excess gas from entering the building and endangering employees. Insulation is used to prevent heat loss and can be in the form of firebrick, ceramic fiber, and other materials.
There are many reasons why direct fire industrial HVAC systems are used for industrial settings. This type of heating is very efficient and helps a company save on heating costs. It is also environmentally clean. A direct fired furnace can use natural or liquefied petroleum gas to obtain extremely high temperatures. Newer designs have flame monitoring tools to make certain the air and gas flow result in a very proficient and clean combustion procedure. Many designs can adjust to outside air conditions by adjusting gas flow to restore a proper balance. These systems also last for a long time when installed by an industrial air conditioning service. Contact your local industrial air conditioning service for more information on the benefits of direct fire systems and the designs available.