WaterFurnace OM1500MW, Руководство пользователя

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Glossary
Learn to speak like your favorite HVAC contractor using these key terms.
AFUE (Annual Fuel Utilization Efficiency): The efficiency
percentage of fossil fuel furnaces. Includes cycling and
fuel losses and other factors.
BTU (British Thermal Unit): The amount of heat needed
to raise the temperature of one pound of water one
degree Fahrenheit.
BTUH:
The number of BTUs produced in one hour. Used to
signify the heating and cooling capacity of a system and
the heat losses and gains of buildings and homes.
CFM (Cubic Feet per Minute):
Volume of air movement.
Used in duct design calculations.
Compressor: The central part of a heat pump system. The
compressor increases the pressure and temperature of the
refrigerant and simultaneously reduces its volume while
causing the refrigerant to move through the system.
Condenser: A heat exchanger in which hot, pressurized
(gaseous) refrigerant is condensed by transferring heat to
cooler surrounding air, water or earth.
COP (Coefficient of Performance): Heating efficiency
rating for a geothermal system. BTU output divided by
BTU input.
Degree Days (Heating & Cooling):
Calculated by adding
the high and low temperatures of the day, dividing by 2,
then subtracting from 65. (Example: High 42, Low 20 = 34
heating degree days.)
Delta T (or
Δ
T):
The change in temperature (degrees).
Usually associated with water or air temperatures.
EER (Energy Efficiency Ratio): Cooling efficiency rating
for geothermal systems. BTU output divided by watt input.
Fossil Fuel:
Any of several types of combustible fuels
formed from the decomposition of organic matter.
Examples are natural gas, propane, fuel oil, oil and coal.
GPM (Gallons per Minute): A reference to the flow rate of
water through the geothermal unit.
Heat Exchanger: A device designed to transfer heat
between two physically separated fluids or mediums (air,
water, or refrigerant) of different temperatures.
Heat Loss:
The amount of energy (BTUs/hr) lost from the
home during cold weather that needs to be overcome/
supplied by the heating system. The amount varies based
on outdoor air temperatures.
Heat Gain: The amount of heat (BTUs/hr) that is absorbed
by the home during hot weather, requiring removal by the
air conditioner in order to cool the home. Varies based on
outdoor air temperatures.
Heat Sink:
The medium (air, water or earth) which receives
heat rejected from a heat pump.
Heat Source: The medium (air, water or earth) from which
heat is extracted by a heat pump.
Hot Water Generator: A device that recovers superheat
from the compressor discharge gas for heating water.
HSPF (Heating Season Performance Factor): Heating
efficiency rating for heat pumps over the course of the
entire heating season.
Infiltration / Exfiltration:
Air movement into the home
through “leaks” (infiltration), or movement of air from
inside the home to the outside (exfiltration).
Relative Humidity: The ratio of the amount of water vapor
actually present in the air to the greatest amount possible
at the same temperature. During heating, RH levels of 40-
50% are generally recommended.
R-Value:
The resistance of heat movement through an
insulating material. Varies with thickness and type.
SEER (Seasonal Energy Efficiency Ratio): Cooling
efficiency rating for heat pumps and air conditioners.
Calculated over the entire cooling season.
Solar Gains:
Heat gain generated through the heating of
walls and windows by the sun.
Ton: In HVAC terms, 12,000 BTUs per hour.
Variable Capacity Compressor: Featured in our 7 Series
units, the compressor can ramp itself up or down from
20% to 130% making it the most efficient compressor
technology available. It will scale output to exactly what is
needed for the home.
Wind Chill:
A still-air temperature that would have
the same cooling effect on exposed skin as a given
combination of temperature and wind speed. Does not
affect heating requirements for your home.
GLOSSARY