143 YEARS OF TOP QUALITY BOILER MANUFACTURING!
EFFECTS OF AIR PROPERTIES

For a burner originally adjusted to 15% excess air, changes in combustion air temperature and barometric pressure cause the following in excess air.

AIR
TEMPERATURE °F
BAROMETRIC
PRESSURE IN. HG
RESULTING
EXCESS AIR %
40
29
25.5
60
29
20.2
80
29
15.0 Initial Setting
100
29
9.6
120
29
1.1
80
27
7.0
80
28
11.0
80
29
15.0 Initial Setting
80
30
19.0
40
31
34.5
60
30
25.0
80
29
15.0 Initial Setting
100
28
5.0
120
27
-5.5

*Expressed as a percent of Stoichiometric air required.