Trane IntelliPak CG-SVX02B-EN, Installation & Operation Manual

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System Start-Up
b. The efficiency of the evaporator.
c. The amount of protection the compressor is
receiving against flooding or overheating.
The recommended range for superheat is 10 to 16 degrees
at the evaporator. Systems operating with less than 10 de-
grees of superheat:
a. Could cause serious compressor damage due to
refrigerant floodback.
b. Removes working surface from the evaporator
normally used for heat transfer.
Systems operating with superheat in excess of 16 degrees:
a. Could cause excessive compressor cycling on
internal winding thermostat which leads to
compressor motor failure.
b. Lowers the efficiency of the evaporator by reducing
the heat transfer capability.
Measuring Superheat
a. Measure the suction pressure at the suction line
gauge access port located near the compressor.
b. Using a Refrigerant / Temperature chart, convert the
pressure reading to a corresponding saturated vapor
temperature.
c. Measured the suction line temperature as close to
the expansion valve bulb, as possible.
d. Subtract the saturated vapor temperature obtained in
step b from the actual suction line temperature
obtained in step c. The difference between the two
temperatures is known as “superheat”.
Note: When adjusting superheat, recheck the
system subcooling before shutting the system
“Off”.
7. Once the checks and adjustments for the operating cir-
cuit has been completed, check and record the:
ambient temperature;
compressor oil level (each circuit);
compressor suction and discharge pressures (each
circuit);
superheat and subcooling (each circuit);
Record this data on an “operator’s maintenance log”
shown in Table 11.
Figure 16
Typical Compressor Locations