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SiME281906E
Outdoor Unit Control
Part 4 Functions and Control
54
4. Outdoor Unit Control
4.1 Overview of Outdoor Unit Controls
4.1.1 Cooling 1 (Control while the compressor is OFF)
1. Compressor frequency instruction
"0 Hz" shows K1M (magnetic contactor for compressor) is ON.
"OFF" shows K1M (magnetic contactor for compressor) is OFF.
4.1.2 Cooling 2 (Control at startup and in operation)
Actuator
Symbol
Compressor OFF
Restart standby
Thermostat OFF
standby
Normal stop
Pressure equalization
control prior to startup
Compressor
M1C
Restart standby
0 Hz (
1)
OFF (
1)
0 Hz (
1)
Outdoor fan
M1F
Restart standby
Step 0
Step 0
Pressure equalization
control prior to startup
Indoor fan
M1F
Instruction not
specified
Instruction not
specified
Instruction not
specified
Control prior to
compressor startup
(indoor fan)
Electronic expansion
valve
Y1E
Controlled by restart
standby
0 pulse
0 pulse
Pressure equalization
control prior to startup
Remarks
For 3 minutes after
compressor is
stopped
After restart standby
until outdoor unit
starts operation (ON)
and thermostat ON
(OFF)
Outdoor unit in
operation: OFF
min. 30 seconds,
max. 150 seconds
Actuator
Symbol
Compressor ON
Startup control
In normal operation
Basic control
Protection control
Basic control
Protection control
Compressor
M1C
Startup control
Low pressure
protection, High
pressure protection,
Discharge pipe
temperature, Inverter
current protection,
Overall current
protection, Piping/
wiring mismatch
detection control
Compressor step
control
Low pressure
protection, High
pressure protection,
Discharge pipe
temperature, Inverter
current protection,
Cooling control with
low outdoor air
temperature, Overall
current protection,
Refrigerant shortage
detection, Piping/
wiring mismatch
detection control
Outdoor fan
M1F
Startup control
Cooling control with
low outdoor air
temperature
Step 8
Cooling control with
low outdoor air
temperature
Indoor fan
M1F
Startup control (indoor
fan)
–
Constant speed
control (indoor fan)
–
Electronic expansion
valve
Y1E
Startup control
Discharge pipe
temperature control
Electronic expansion
valve control
Discharge pipe
temperature control
Remarks
min. 2 minutes, max. 5 minutes
–