Browse by letter:
A |
B |
C |
D |
E |
F |
G |
H |
I |
J |
K |
L |
M |
N |
O |
P |
Q |
R |
S |
T |
U |
V |
W |
X |
Y |
Z
| Term | Definition |
|---|---|
| Handhole | An access opening in a pressure part usually not exceeding 6" in its longest dimension. |
| Handhole Cover | A handhole closure. |
| Hard Water | Water which contains calcium or magnesium in an amount which require an excessive amount of soap to form a lather. |
| Hardness | A measure of the amount of calcium and magnesium salts in water. Usually expressed as grains per gallon or ppm as CaCO3. |
| Heat Available | The thermal energy above a fixed datum that is capable of being absorbed for useful work. |
| Heat Balance | An accounting of the distribution of the heat input, output and losses. |
| Heat Exchanger | A vessel in which heat is transferred from one medium to another. |
| Heat Release Rate | Rate that describes the heat available per square foot of heat-absorbing surface in the furnace or per cubic foot of volume. |
| Heating Surface | Those surfaces which are exposed to products of combustion on one side and water on the other. This surface is measured on the side receiving the heat. |
| Heating Value | The quantity of heat released by a fuel through complete combustion. It is commonly expressed in Btu per lb, per gallon, or cu-ft. |
| High Gas Pressure Control | A control to stop the burner if the gas pressure is too high. |
| High Oil Temperature Control | A control to stop the burner if the oil temperature is too high. |
| Hydrocarbon | A chemical compound of hydrogen and carbon. |
| Hydrostatic Test | A strength and tightness test of a closed pressure vessel by water pressure. |
