When we think about building heat, our first consideration may be of the forced-air variety. While that might work for some, independent reports reveal that gas fired infra-red heating can save 20 to 50 percent in fuel consumption over forced air heating.
Low Intensity gas fired infra-red heating systems emulate the true efficiency of the sun by generating radiant heat energy. They consist of three main components: a burner control box, black coated radiant emitter tubes and a highly polished reflector assembly. The heaters are typically suspended from the ceiling by chains and controlled by a thermostat. They can be installed either vented or unvented, may use outside air for combustion if necessary and may be installed in different configurations depending on the heating requirements.
The two types of infra-red heating are High Intensity and Low Intensity. High Intensity heaters require high mounting heights due to higher concentrated amounts of infra-red energy. They utilize a highly polished reflector to help direct heat where its required, and are typically used to spot heat areas with few workers and operate unvented.
Low Intensity heaters have an enclosed flame. When heat is required, the burner control box ignites a gas/air mixture and hot gases are pushed through steel radiant tubing by an internal fan. As these gases pass through the assembly, the tubing is heated and emits infra-red energy, which is then directed toward the floor by highly polished reflectors. This energy is absorbed by objects in its path, such as the floor, machinery and people. Objects in the path of the infra-red energy in turn re-radiate this heat to create a comfort zone at the floor level. This method of heating, as opposed to filling a room with warm air, allows the source of heat to begin at the floor level and not the ceiling. With a forced air system, heat escapes as doors are opened. When the doors close the system will have to reheat the air as if from a cold start up. However, with infra-red heat the floor acts as a reservoir. When doors are opened the slab loses very little of its heat and when the doors close this mass acts as a huge heat sink to warm the surrounding air. This creates the most efficient and effective heating method under the diverse conditions present in most commercial and industrial applications.
There are a few important things to consider when using radiant heat. While the heating units are easy to live with, care needs to be taken when designing the system to maintain clearances to combustibles. Infra-red radiant heaters require higher clearances than forced air units. Therefore, a mounting height of 10' or higher is recommended depending on the application and the model.
Very little maintenance is required, especially when bringing in outside air for combustion. This is recommended when dust or contamination is present inside the building. Periodic wiping of the reflectors is beneficial, not only for safety but for the overall efficiency of the heater. This is easily done by wiping the surfaces of the unit occasionally or blowing it off with an air-compressor hose.
If you are one to count pennies you might want to stay with the forced-air method. But, if you can live with a small initial investment, radiant heating might be a wise choice. Gas line connections must be considered and installing the unit is at least a two-person job. The initial cost of a standard, unitary tube heater of forty feet long will run approximately $1,100. Therefore, up-front costs are higher than traditional heating methods. However, this investment will pay for itself over a short period of time due to the energy saving benefits of radiant heaters. Interested in even more fuel savings? Installing a system that incorporates two stage technology can offer an additional 12 percent fuel savings over a standard single stage radiant heater.
In the end, it comes down to whether you wish to provide a cost-effective and comfortable heat source in your application. Gas fired infra-red heaters offer the flexibility of placing heat where and when it is needed. This ability coupled with excellent operating costs, gives a clear advantage to infra-red heaters. And if you want to get the most for your money go with heaters equipped with two stage technology. You can rest assured that providing a comfortable environment within your application will be well received by both you and other building occupants.