Kenmore 796.8159 series, Use & Care Manual, Page: 8 / 76

8
FEATURES AND BENEFITS
WHAT IS A HEAT PUMP DRYER?
What is heat pump technology?
Heat pump dryers use a combination of conventional
heating elements and a heat pump system to dry your
clothes. The heat pump recovers heat from the hot, moist
air that is normally exhausted to the outside and lost.
Using a heat pump to preheat the air coming into the
dryer recovers this heat and saves electricity, because
it takes less electricity to move the heat than to create
it with a conventional heater. This heat pump dryer has
been designed to save you money.
How does it work?
Heat naturally moves from warmer areas toward cooler
areas. Heat pumps control this movement by trapping
hot air. Rather than using a lot of energy to create heat,
heat pumps use a little energy to transfer heat from one
place to another using a heat exchanger.
The heat pump in the dryer is similar to those used in
air conditioners or dehumidifiers. The cold part of the
system is used to condense water and cool the exhaust
air, while the hot part of the system is used to heat the
air coming into the drum to dry the clothes.
2. Vapor
Vapor is channelled into an electric
compressor, increasing the pressure
and temperature of the vapor.
Condensed refrigerant
High pressure side
Hot gas
Compressor
Expansion
valve
Cool gas
Cold refrigerant
Low pressure side
Heated air into
dryer drum
Heat ex
changer
Ev
apor
at
or
Exhaust air
Room air
4. Condensed vapor
Condensed vapor returns to liquid,
passes through the expansion valve,
reducing pressure and temperature.
The cycle repeats.
1. Exhaust
Hot, moist air from the
dryer dru
Pp
ows over the
evaporator. The refrigerant
boils and evaporates
cooling the air and
condensing the moisture.
3. Room Air
Cool r
RRPDLUp
ows over
the hot condenser as
it enters the dryer. The
refrigerant condenses and
cools, preheating the air
entering the dryer.
How does the heat pump dryer use less energy
than a conventional dryer?
 Because heat pumps transfer heat instead of
creating it from scratch, they use less energy to
produce heat than regular heaters, in most cases.

In conventional dryers, all the energy that is used
to evaporate the moisture in the clothes is vented
outside and lost. The heat pump dryer technology is
able to recover some of this wasted energy and use
it to evaporate more moisture, saving energy.
How much energy can it save?
The amount of energy saved will depend on cycle
selection, load size, options, vent condition, and many
other factors.
The cycles and options that save the most energy will
take longer to dry, but the energy saved in heating more
than offsets the energy used to tumble the clothes, which
is relatively small.