Superheat (Sh) And Subcooling (Sc); Target Superheat (Tsh) - Fieldpiece SMAN SM480V Operator's Manual

Superheat (SH) and Subcooling (SC)

Superheat is the amount of heat added to
refrigerant after changing to a vapor in the
evaporator Subcooling is the amount of heat
removed from refrigerant after changing to a
liquid in the condenser View both live at the
same time!
1. Use ARROWS to select the system refrigerant.
2. Close all manifold valves.
3. Connect EPA approved refrigerant hoses to LOW and HIGH side ports.
4. Fully plug pipe clamp thermocouples into SLT and LLT rear jacks.
5. Hand tighten both the LOW side hose to suction line service port and
the HIGH side hose to the liquid line service port.
6. Clamp the SLT thermocouple to the suction line between the
evaporator and compressor, at least 6 inches from the compressor.
7. Clamp the LLT thermocouple to the liquid line between the
condenser and metering device, as close to the service port as
possible.
8. Purge hoses as you open HIGH and LOW manifold valves.
9. View superheat and subcooling in real-time.
• Ensure system has stabilized before using superheat or subcooling to
adjust the charge of the system.
• To add or remove refrigerant connect the tank/cylinder/machine to
the REF port. Use the manifold valves to precisely charge or recover
refrigerant as needed. Follow recommended charging or recovery
practices from equipment manufacturer and training.
• When superheat and/or subcooling cannot be calculated, "- - - - "
will be displayed. If superheat and/or subcooling is negative, "Below
Typical Range" will show. In rare cases this is normal, but usually a
thermocouple is disconnected or the selected refrigerant is incorrect.
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Target Superheat (TSH)

Compare target superheat (TSH) to actual
superheat (SH) when charging fixed orifice
air conditioning systems TSH is continually
calculated from indoor wet bulb (IDWB) and
outdoor dry bulb (ODDB) temperatures
IDWB: By default, this is a manually set value of 60.0°F.
For a live measurement, assign the optional model JL3RH wireless
psychrometer (page 26).
ODDB: By default, this is the live measurement of the ODDB
thermocouple jack. If you prefer a static measurement, assign a
manual value (page 27).
1. Connect the included type K bead thermocouple to the ODDB
thermocouple jack. Use the alligator clip to locate the bead in a
shaded area of the condenser to measure the temperature of air
entering the condenser.
2. Press VIEW until ODDB is displayed to verify the measurement.
If you changed ODDB to a manually set value, it will be used to
calculate TSH but will not be displayed.
3. Measure IDWB after the filter, just in front of the indoor coil. If
a psychrometer is assigned, you can press AIR until wet bulb is
displayed to verify the measurement.
4. Press VIEW until TSH is displayed.
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