| 摘要 |
<p>The directly heated air heater has a combustion chamber (40) for burning fuel to produce heat. A heat exchanger is provided for transferring heat from the combustion chamber and exhaust gases, generated in combustion chamber. The hot air channel is divided into a sub-region, such that partially heated air channels (114,115) are provided for guiding hot air proportions under different temperatures. The hot air channel is formed for feeding heating air portion at a lower temperature, and meets an end of the exhaust pipe to cool the exhaust gas temperature below the condensation temperature.</p> |
