Fujitsu Mini-Split Manual page 5

Heat Pumps Provide Heat When it is Chilly
Because refrigerant is naturally much colder than outdoor
temperatures even on a very cold day, it actually absorbs heat
from outdoors, and transfers the heat it absorbs outside to
within your home. The refrigerant's physical properties do this
naturally. What you pay for is the electricity to pump refrigerant
via copper tubing from outdoors to indoors. Because we move
the heat rather than create it (as electric baseboard or resistant
heat does), we can deliver up to 4 times the heat for the energy
we consume!
Air Conditioners Provide Cooling When It's Warm
Come spring and summer, simply reverse the process and
put the same system into "cooling mode" and transfer heat
from indoors to the outside. For many climates, the advanced
technology that goes into these units creates a far more cost
effective alternative to either gas or oil-fired units for heat, or
a central ducted system for air conditioning. Fujitsu's mini-splits
come in both cooling-only models or heat pumps, which
provide both heating and cooling.
Electric Heaters versus Heat Pumps
An electric heater converts electricity directly to
heat, and if we assume that the heat loss is zero,
the output from one kilowatt input is one kilowatt
or 3,400 BTU and the EER is 3.4.
*EER (Energy Efficiency Rating) = Rated BTU capacity divided by total kW input.
Basic Heat Pump Configuration
Heat In
compressor
Basic Air Conditioner Configuration
Heat Out
compressor
Heat pumps are more efficient than some other forms
of heating because heat pumps do not actually create
heat - they just move it from one place to another.
For example, the output of an efficient 10 EER heat
pump is triple that of an electric heater.
Heat
Out
expansion
valve
Heat
In
expansion
valve
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