Carrier 38MPRA Series - COOLING MODE OPERATIONS

16 Specifications subject to change without notice. SG-38MPRA-02
FAN Mode
When the FAN mode is activated:
• The outdoor fan and compressor stop.
• Temperature control is disabled and the indoor room temperature
is displayed.
• The indoor fan speed can be set to 1%~100%, or AUTO.
• The louver operations are identical to those in COOLING mode.
• Auto fan: In FAN-ONLY mode, the AC operates the same as auto
fan in the COOLING mode with the temperature set at 75F
(24°C). (Tsc=75°F (24°C)).
COOLING Mode
Compressor Control
Reach the configured temperature:
1. When the compressor runs continuously for less than 120 minutes:
• If the following conditions are satisfied, the compressor ceases
operation.
• While the calculated frequency (fb) is less than the minimum
limit frequency (FminC).
• While the protective time is more than or equal to ten minutes.
• While T1 is lower than or equal to (Tsc-CDIFTEMP 31  F (-0.5  C)
NOTE: CDIFTEMP is the EEPROM setting parameter. It
is 4
°F (2°C).
2. When the compressor runs continuously for more than 120
minutes:
• If the following conditions are satisfied, the compressor ceases
operation.
• When the calculated frequency (fb) is less than the minimum
limit frequency (FminC).
• When the protective time is more than or equal to ten minutes.
• When T1 is lower than or equal to (Tsc-CDIFTEMP).
NOTE: CDIFTEMP is the EEPROM setting parameter. It
is 4
°F (2°C).
3. If one of the following conditions is satisfied, regardless of time:
• The compressor running frequency is more than the test
frequency.
• When the compressor running frequency is equal to the test
frequency, T4 is more than 59F (15C) or no T4 or T4 fault.
• Change setting temperature
• Turbo or sleep function on/off
• Various frequency limit shutdown occurs
NOTE: CDIFTEMP is EEPROM setting parameter. It is
4
°F (2°C).
Indoor Fan Control
1. In the COOLING mode, the indoor fan operates continuously. The
fan speed can be set to 1%-100%, or AUTO.
2. AUTO fan
• Descent Curve
• When T1-Tsc is lower than or equal to 6F (3.5C), fan speed
reduces to 80%;
• When T1-Tsc is lower than or equal to 2F (1C), fan speed
reduces to 60%;
• When T1-Tsc is lower than or equal to 1F (0.5C), fan speed
reduces to 40%;
• When T1-Tsc is lower than or equal to 0F (0C), fan speed
reduces to 20%;
• When T1-Tsc is lower than or equal to -1F (-0.5C), fan
speed reduces to 1%.
• Rise Curve
• When T1-Tsc is higher than 0F (0C), fan speed increases to
20%;
• When T1-Tsc is higher than 1F (0.5C), fan speed increases
to 40%;
• When T1-Tsc is higher than 2F (1C), fan speed increases to
60%;
• When T1-Tsc is higher than 3F (1.5C), fan speed increases
to 80%;
• When T1-Tsc is higher than 7F (4C), fan speed increases to
100%.
Outdoor Fan Control
• The outdoor unit runs at a different fan speed according to T4 and
the compressor running frequency.
• For different outdoor units, the fan speeds differ.
Condenser Temperature Protection
When the condenser temperature exceeds a configured value, the
compressor ceases operations.
Evaporator Temperature Protection
When the evaporator temperature drops below a configured value, the
compressor and the outdoor fan cease operations.