|Useful Definitions of Terms:
Some of the terms used in HVAC(R)
HVAC(R): Heating Ventilation and Air
Conditioning an R may be added to represent Refrigeration.
Split system: Refrigeration system
where the refrigerant is piped from one part to another, such as residential
heat pump or a/c system.
Packaged or self-contained: Refrigeration
system where everything including the air moving hardware is kept in one
box, such as a window air conditioner or a roof-top unit.
Forced air: heating and or cooling
system that connects to the conditioned space with duct-work
that uses air as the moving fluid. The heating or cooling can come from
any number of sources.
Radiant: System that uses hot surfaces to
radiate or convect heat into the environment. Without the use of fans or
Heat Pump: Refrigeration device that can
be used to move heat to or from air or water, or to or from air to water
then the water is used to heat or cool air. In some parts of the world
they are also known as "Reverse Cycle".
Evaporator: The part of a refrigeration
system that gets cold. It is called the evaporator because it is the part
of the system that evaporates the refrigerant from liquid to vapor.
Condenser: The part of a refrigeration system
that gives up heat from the refrigerant and changes the refrigerant from
a vapor to a liquid.
Condensers can be either water cooled or air cooled.
Compressor: The heart of any refrigeration
system that pumps the refrigerant.
(absorption systems that use ammonia or lithium bromide
do not have compressors). Compressors
can be reciprocating, rotary, scroll, disc, or screw.
Receiver: Tank on the liquid side of a system
that holds excess refrigerant in the system that needs to be there for
Accumulator: Tank on the suction side of a system
that holds excess refrigerant to prevent slugging the compressor with liquid.
Outdoor coil: The coil on a heat pump system that
is located out side or in the ground loop of a groundsourced
heatpump. This is so not to be confused with the condensor on an airconditioning
Indoor coil: The coil on a heat pump that is located
inside. This is so not to be confused with the evaporator on an airconditioning
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read about more heatpump problems please visit this page.
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