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      RLYSeries Fuel Gas Hot Air Furnaces: The fuel of the series fuel gas hot air furnace is burned through the burner to produce high-temperature gas. The heat from the high-temperature gas is then transferred to the heated air by the hot air furnace equipped with enhanced heat exchange measures. After the heat is dissipated, the high-temperature gas is cooled down to250°CBelow, the air is exhausted by the blower fan. Air requiring heating is delivered to the hot air furnace through an optional blower, absorbs heat, and is then discharged at the specified temperature. When the hot air temperature reaches the upper limit set, the burner automatically stops firing or switches to a low flame. When the hot air temperature drops to the lower limit, the burner reignites and resumes operation or switches to a high flame. The speed of the temperature program can be adjusted by regulating the air inlet valve.