71
OCH722A
Indication
Error
Detailed
reference
page
Controller circuit board
Content
s
Check
code*
Inspection method
LED1 (Green) LED2 (Red)
3 blinking 1 blinking Abnormality of discharge temperature
(TH4) and Comp. surface temperature
(TH33)
U2
1
Check if stop valves are open.
2
Check if connectors (TH4, LEV-A) on controller
circuit board are not disconnected.
3
Check if unit is filled with specified amount of
refrigerant.
4
Measure resistance values among terminals
on linear expansion valve using a tester.
P46
Abnormality of superheat due to low
discharge temperature
U7
P47
2 blinking Abnormal high pressure (High pressure
switch 63H operated.)
U1
1
Check if connector(63H)(63L) on controller
circuit board is not disconnected.
2
Check if filter is not dirty.
3
Measure resistance values among terminals
on linear expansion valve using a tester.
P46
Abnormal low pressure
UL
P48
Abnormal low brine flow rate (flow switch
operated)
UA
P48
3 blinking Abnormality of brine pump motor
rotational speed
U8
1
Check the brine pump
motor.
2
Check if connector (TH3) (63HS) on controller
circuit board is disconnected.
P47
Protection from overheat operation (TH3)
Ud
─
4 blinking Compressor overcurrent breaking (Start-
up locked)
UF
1
Check looseness, disconnection, and
converse connection of compressor wiring.
2
Measure resistance values among terminals
on compressor using a tester.
3
Check leakage of refrigerant.
P48
Compressor overcurrent breaking
UP
P48
Abnormality of current sensor (P.B.)
UH
P48
Abnormality of power module
U6
P47
5 blinking Open/short of heat pump unit thermistors
(TH4, TH33)
U3
1
Check if connectors (TH3, TH32, TH34, TH4,
TH33 and TH7) on controller circuit board and
connector (CN3) on power circuit board are
not disconnected.
2
Measure resistance value of heat pump unit
thermistors.
P46
Open/short of heat pump unit thermistors
(TH3, TH32, TH34, TH7 and TH8)
U4
P47
6 blinking Abnormality of heat sink temperature
U5
1
Measure resistance value of outdoor
thermistor(TH8).
P47
7 blinking Abnormality of voltage
U9
1
Check looseness, disconnection, and
converse connection of compressor wiring.
2
Measure resistance value among terminals on
compressor using a tester.
3
Check if power supply voltage decreases.
4
Check the wiring of X52CA.
5
Check the wiring of CNAC.
P47-
P48
4 blinking 1 blinking Abnormality of room temperature
thermistor (TH1)
P1
1
Check if connectors on FTC are not
disconnected.
2
Measure resistance value of FTC thermistors.
P44
Abnormality of pipe temperature
thermistor /Liquid (TH2)
P2
P44
Abnormality of tank temperature
thermistor
P9
─
4 blinking Abnormality of pipe temperature
P8
1
Check if FTC thermistors(TH2) are not
disconnected from holder.
2
Check if stop valve is open.
─
* Check code displayed on remote controller
** Refer to service manual for indoor unit.
Summary of Contents for EHGT17D-YM9ED
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