Application guidelines
33
FRCC.PC.004.A9.22
Installation and service
Suction gas superheat
The optimum suction gas superheat is 18°F. A
lower superheat value will contribute to better
system performance (higher mass flow and
more efficient use of evaporator surface). Low
super heat values however increase the risk of
unwanted liquid floodback to the compressor.
For very low superheat values an electronically
controlled expansion valve is recommended.
The maximum allowable superheat is about
54°F. Higher values can be accepted but in these
cases, tests have to be performed to check that
the maximum discharge temperature of 266°F
will not be exceeded. Note that high superheat
values decrease the compressor application
envelope and system performance.