1. Condensing Low-Nitrogen Combustion Emission of Gas Boilers—Fully Premixed Variable Frequency Combustion Fully Premixed Technology for Condensing Low-Nitrogen Combustion Emission in Gas Boilers: This technology involves uniformly mixing air and gas for rapid and complete combustion. The fully premixed technology draws gas and air through a Venturi tube, where they are stirred by a fan and thoroughly mixed before entering the burner head. The premixing chamber further disperses gas and air molecules evenly, ensuring a more complete mixture. Similar to how sawdust burns faster and more completely than a log of wood, this method allows combustion speed to no longer be limited by physical conditions such as gas diffusion rate, resulting in faster combustion and higher efficiency. Variable Frequency Technology for Condensing Low-Nitrogen Combustion Emission in Gas Boilers: A top-tier DC variable frequency control system automatically adjusts the output load in response to changes in demand. Based on the load, it precisely regulates the amount of gas and air entering the combustion chamber, ensuring optimal combustion conditions at all times. 2. Condensing Low-Nitrogen Combustion Emission of Gas Boilers—Surface Combustion A metal mesh burner head splits the flame into countless tiny flames spread over a large area, evenly heating the heat exchanger. The burner head is made of special metal fibers and utilizes radiant heat transfer to enhance heat exchange efficiency. The key material used in metal fiber gas burner heads is a special iron-chromium-aluminum fiber, with a diameter of approximately 30–50 μm, a combustion intensity of up to 2500 kW/m3, and high-temperature resistance up to 1300°C. Due to the compact structure of the premixed flame and its close proximity to the heating surface, the combustion chamber can be designed smaller to take advantage of this feature. Additionally, the metal fiber burner employs radiant heat transfer, further improving heat exchange efficiency. During combustion, the flame on the burner surface consists of countless blue flames forming a flame surface, a state known as surface combustion, which is the optimal combustion state for natural gas. This combustion method ensures complete gas combustion, uniform heat generation, and no localized high temperatures, preventing the formation of nitrogen oxides and carbon monoxide. Flue gas emissions are significantly lower than national standards, with nitrogen oxide emissions below 15 mg/m3. Fully Premixed Metal Fiber Surface Combustion involves thoroughly mixing air and natural gas in precise proportions before they enter the combustion chamber. This ensures complete combustion of natural gas while reducing the required air volume, eliminating excess air, and increasing the dew point of the flue gas, allowing it to enter the condensation stage earlier to further improve combustion efficiency. The combustion process consists of tens of thousands of small flames with a diameter of 0.01 mm, significantly reducing flame temperature and minimizing the production of nitrogen oxides (NOx). Under operating conditions, NOx emissions can be controlled to as low as approximately 10 mg/m3 and remain below 15 mg/m3 across all operating conditions, fully meeting environmental requirements.