Thermal overload and fusible link
To prevent a large current draw at one time when
Air to air, water to air, air to water, water to water
It moves heat from a low-temperature heat source to a
higher-temperature heat sink
A reversing valve which reverses the direction of refriger-
Air-source heat pumps circulate less refrigerant at low
ambient temperatures, and the refrigerant not being used
must be stored somewhere.
Auxiliary heat is another heat source added to make up
the difference between the heat pump capacity and the
The solenoid coil controls the pilot valve, which controls
the pressure to the ends of the reversing valve. The pres-
sure difference between one end of the valve and the
other causes the cylinder to shift. The end the valve is
shifted to becomes the evaporator, and the other end
becomes the high side.
EER is a steady-state measurement that doesn’t take into
consideration starting, stopping, and different operating
conditions. SEER is a seasonal measurement that takes
all these factors into account.
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