Hitachi RAC-18WPC - Block Diagram

1
2
3
EEPROM
Relay drive circuit
Reversing valve
drive circuit
Electric expansion
valve drive circuit
Electric expansion
valve
Reversing valve
Outdoor
Fan motor
Is
Ip
Id
Ip
Id
(AX-12C872)
Outdoor DC fan motor
drive circuit
Compressor
motor
Compressor
drive circuit
BLOCK DIAGRAM
OUTDOOR UNITPower source
1 O 230V 50Hz
Outdoor microcomputer
Indoor / Outdoor
interface circuit
Power circuit
Control power circuit
Reset circuit
Overheat thermistor
Defrost thermistor
Outdoor temperature
thermistor
Oscillator clock
circuit
L
N
MODEL RAC-18/25WPC
Indoor
unit
13