Refrigeration Piping Charging Residential AirConditioning R

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temperature R-502 compressor at -40ºF evaporating temperature will lose almost 6% of
its rated capacity for each 1 psi suction line pressure drop. Normally accepted design
practice is to use a suction line pressure drop equivalent to a 2ºF change in saturation
temperature.
Of equal importance in sizing the suction line is the necessity of maintaining adequate
velocities to properly return oil to the compressor. Studies have shown that oil is most
viscous in a system after the suction vapor has warmed up a few degrees from the
evaporating temperature, so that the oil is no longer saturated with the refrigerant.
This condition occurs in the suction line after the refrigerant vapor has left the
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