What does the net stack temperature refer to?

The net stack temperature is defined as the temperature difference between the flue gas and the surrounding air. This measurement is crucial for understanding the efficiency of the combustion process and how heat is being transferred through the system. When the flue gas exits the boiler or furnace, it carries heat that could potentially be used to warm water or air for heating purposes. By comparing the temperature of the flue gas to that of the surrounding air, technicians can assess how effectively heat is being utilized and whether there might be heat loss occurring.

This temperature difference can provide insights into the performance of the burner and the efficiency of the heating system as a whole. Efficient systems will have a smaller temperature difference, indicating that more heat is being transferred to the intended heating medium rather than being wasted as exhaust. Understanding this concept is vital for optimizing HVAC systems to improve their performance and reduce energy consumption.