To secure safe and efficient operation of gas or fuel oil burners it is common to test the burners for
When the CO2 content of the flue gas is low (less than 8 percent) heat is lost up the chimney and the operation is inefficient.
Low carbon dioxide content may be caused by
When the CO2 content of the flue gas is too high it is common with excess smoke in the flue gas. High carbon dioxide content may be caused by
Smoke in flue gas indicates poor burner performance. The amount of smoke can be measured with a smoke tester where smoke particles set on a filter paper are interpreted according a Bacharach scale.
Smoky combustion can be caused by
The "net stack temperature" is the difference between the flue gas inside the chimney and the room temperature outside the burner. Net stack temperatures above 700oF (370oC) are in general to high. Typical values are between 330 - 500oF (160 - 260oC).
High stack temperatures may be caused by