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Appendix
II.
Example of a Tecumseh
Hermetic Compressor
A Tecumseh hermetic compressor is a direct-con-
nected motor compressor assembly enclosed within
a steel housing and designed to pump low pressure
refrigerant gas to a higher pressure.
The major internal parts of a Tecumseh hermetic
compressor are shown in Figure A-2 and are listed in
the same sequence as that of the refrigerant gas flow
through the compressor. First, the suction is drawn
into the compressor housing, then to and through
the electric motor which provides power to the
crankshaft. The crankshaft revolves in its bearings,
driving the piston(s) in the cylinder(s). The crank-
shaft is designed to carry oil from the oil pump in
the bottom of the compressor to all bearing surfaces.
Refrigerant gas surrounds the compressor crankcase
and motor as it is drawn through the compressor
housing and into the cylinder(s) through the suction
muffler and suction valves. As the gas is pressured by
the moving piston, it is released through the dis-
charge valves, discharge muffler and compressor dis-
charge tube.
Some Tecumseh hermetic compressors are low pres-
sure housing compressors. These compressor hous-
ings are not normally subjected to discharge pressure
— operating instead at relatively low suction pres-
sures. These Tecumseh compressors are generally
installed on equipment where it is impractical to
disconnect or isolate the compressor from the sys-
tem during pressure testing; therefore, do not exceed
a field leak test pressure of 150 PSIG when pressur-
izing such a complete system.
Many Tecumseh hermetic compressors contain
internal motor protectors — the details of these are
covered “Hermetic Compressor Thermal Protectors”
on pages 19-29.
