Steam Boiler:is a fired or unfired closed pressure vessel used to generate steam by application of heat.

Low Pressure Boiler is a boiler in which steam is generated at pressures not exceeding 15 PSI.

High Pressure or Power Boiler is a boiler in which steam or other vapor is generated at pressure exceeding 15 PSI.

Small Power Boiler is a boiler with pressure exceeding 15 PSI but not exceeding 100 PSI and having less than 350,000 BTU's per hour heat output.

Miniature Boiler is a boiler that does not exceed any other following limits:
1. 16" insided diameter of shell.
2. 5 cu. ft gross volume, exclusive of casing and insulation.
3. 20 sq. ft. water heating surface.
4. 100 PSI maximum allowable working pressure.

Hot Water Boiler:is a fired or unfired pressure vessel used to heat water.

Low Pressure Boiler is a boiler, which does not operate at water pressures exeeding 160 PSI or water temperatures exceeding 250°F.

High Pressure or High Temperature Power Boiler is a boiler used to heat water or a liquid temperatures above 212°F a pressure exceeding 160 PSI Or to a temperatures exceeding
250° F regardless of pressure.

Miniature Boiler is a high temperature boiler with the same limitations as abobe paragraph I, D.

Water Heater:
  an appliance designed primarily to heat supply water and is equipped
with automatic controls limiting water temperatures to a maximum of 210ºF.

Automatic Boiler is a boiler equipped with all devices required by the Code to maintain
burner firing conditions, the pressure and/or temperature, the water level for fully
automatic and safe operation within predetermined limits without manual manipulation.

Packaged Boiler is a boiler equipped and shipped complete with fuel burning
equipment, accessories and automatic controls.

Steam Boiler Horsepower is the term used to rate the generating capacity output of a
steam boiler. A boiler horsepower is equivalent to the evaporation of 34.5 lbs. of water
or 4.14 gallons per hour at a temperature of 212ºF into steam at the same temperature.

Or, 1 boiler horsepower is the evaporation of 30 lbs. of water per hour into steam at 70
PSI gauge pressure from an initial water temperature of 100ºF. A boiler horsepower is
equivalent to an output of 33,475 BTU's per hour.

Certified Boiler Inspector is a person qualified to make inspections or examinations of
boilers or tanks according to the rules which the vessel is constructed, who has an
unrevoked Certificate of Competency issued by the State and National Board and who
is employed by anyone of the following:
1. A County
2. A City
3. An Insurer
4. An employer for the purpose of inspecting only tanks and boilers under his
jurisdiction.

is defined as a closed vessel or tank having a nominal
internal diameter exceeding 6" and a volume exceeding 1½ cu. ft., for liquids, gases or
vapors subjected to pressure exceeding 15 PSI or steam under any pressure.

Pilot is a burner smaller than the main burner, which is ignited by a spark or other
independent and stable ignition source, and which provides ignition energy required to
immediately light-off the main burner.

Continuous Pilot is a pilot that burns without turndown throughout the entire period that
the boiler is in service, whether or not the main burner is firing.

Intermittent Pilot is a pilot which burns during the light-off and while the main burner is
firing, and which is shut off with the main burner.

Interrupted Pilot is a pilot which burns during light-off and which is shut off during
normal operation of the main burner.