Low NOx Heaters
The American Heating Company serpentine coil heater has many distinct advantages when a low NOx heater or burner system is required. Some of these advantages include:
1. Large Combustion Volume – The large combustion volume in the radiant section of our heater is due to the fact that we use a serpentine coil with space between the tubes. This large combustion volume becomes an advantage for low NOx because it reduces the volumetric heat release, as well as the overall fire box temperature, thereby reducing NOx formation.
2. Low Stack Temperature – The convection section of the American Heating Company heater is designed to reduce the gas temperature leaving this section to 100ºF. above the incoming hot oil temperature. The lower the gas temperature (with the flue gas recirculation design) to the burner, the less NOx is formed during combustion.
3. Large Flue Gas Recirculation Duct – The American Heating Company design has the stack at the opposite end of the burner. There is relatively long run of flue gas recirculation duct required. We oversize this duct and, in most cases, will use a 10 inch diameter duct. This duct will be uninsulated. The large surface area of duct will quickly allow the flue gas to give up heat and reduce the gas temperature even further at the entrance to the burner. This reduced temperature will, again, allow for less NOx formation.
American Heating Company has heaters in service with NOx levels of less than 9 PPM total NOx, and less than 50 PPM Co. We believe using flue gas recirculation is the most efficient way to achieve the lowest NOx level but we also use burner models that can achieve 9PPM NOx without a flue gas duct.
