General Theory Of Operation - Whirlpool WED99HEDW0 Technical Education

HybridCare™ Heat Pump Technology
A typical dryer uses large amounts of energy; this dryer
consumes a fraction of the energy by recycling and reclaiming
heat. The HybridCare™ dryer is a ventless heat pump dryer
that uses a refrigeration system to dry and recycle the same
air. The laundry is dried with low temperatures; therefore it
may feel cooler than expected during and after the drying
process.
The heat pump dryer's heating phase is longer than in
traditional dryers. The first 10 to 20 minutes use little or no
heat during the drying time. If possible, do not open the dryer
door during the process as heat can escape from the drum and
can make longer drying times.
HybridCare™ Heat Pump Dryer Heating System
Heating System - instead of two electric heaters, the HybridCare™ dryer substitutes the compressor (sealed system) for one of
the heaters. The Compressor and Heater act very similarly as the two heaters did in the Whirlpool direct drive dryer. Previously,
each heater was connected to its own heater relay. In HybridCare™, the compressor is controlled by one of the relays.
Sealed System Theory of Operation:
Mechanical heat pumps exploit the physical properties of a volatile evaporating and condensing fluid known as a refrigerant. The
heat pump compresses the refrigerant to make it hotter on the side to be warmed, and releases the pressure at the side where
heat is absorbed. Refer to the diagram below for the following operations:
1. The refrigerant (R134a), in its gaseous state, is pressurized (heated) and circulated through the sealed system by the
compressor.
2. The now hot and highly pressurized gas is sent to the condenser section of the heat exchanger until it condenses into a high
pressure, moderate temperature liquid. The condenser heats up the process air which will be sent to the drum.
3. The condensed refrigerant then continues to the post condenser―with the help of the auxiliary fan―begins the cooling of
the refrigerant.
4. The refrigerant then passes through a pressure-lowering device such as an expansion valve, or in this application, a capillary
tube further decreasing the temperature of the refrigerant.
5. The low pressure liquid refrigerant then enters the evaporator section of the heat exchanger, in which the fluid absorbs
heat, boils and is converted to a gas. This is accomplished when the fan blows the hot process air (from the drum) across the
evaporator, which also helps to remove moisture from the humid process air. The refrigerant then returns to the compressor
and the cycle is repeated.
3 - Post Condenser
1 - Compressor
Assembly
Figure 1 - Sealed System

General Theory of Operation

HIGH SIDE
4 - Capillary
LOW SIDE
Warm Humid Process Air In From Drum
Benefits of HybridCare™ Heat Pump
• ENERGY: Regenerates energy to reduce overall energy
consumption. Capability to use less heat than vented dryer.
• PERFORMANCE: Three available modes allow flexibility to
manage drying performance and energy savings.
• VENTLESS DESIGN: Allows installation in more locations
throughout the home.
New Sounds from HybridCare™ Heat Pump
• Dryer runs on a compressor like your refrigerator and you
may notice a hum from the compressor.
• The water from wet clothes is pumped out to your drain.
You may notice a gurgling sound occasionally.
Hot Process Air Out to Drum
Tube
5 - Evaporator
HybridCare™ Dryer with Heat Pump Technology
GENERAL INFORMATION
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2 - Condenser
Heat Exchanger
Assembly
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