Mitsubishi Heavy Industries SRRM40HENG-L, Handbook, Page: 89 / 1106

87
SRK-H
Is connection to connector
good?
Is thermistor resistance
value normal?
Replace PCB.
Repair connector.
Replace thermistor.
No
No
Yes
Yes
Anormality of thermistor Disconnection of thermistor and defective connection of connector
Chart for thermistor temperature
resistance characteristics
(Disconnection)
(Short circuit)
Resistance value
(k
Ω
)
Temperature (
°
C)
(4) Trouble Diagnostic Procedures
Unit malfunctions or
does not stop.
Replace PCB.
Microcomputer rarely
mis-starts even during
times or power supply
or power failure, but, it
can sometimes occur
during those times. If it
occurs, check the opera-
tion, when the result is
positive then proceed as
normal.
Runaway of micro-
computer
Remove receptacle.
Insert it after 3 min.
and operate.
No change.
Normal operation.
Indoor lamp of
indoor unit does not
illuminate.
Check receptacle voltage.
Check if PCB fuse is blown.
Check varistor.
Check transformer secondary
voltage
Replace PCB.
Replace fuse.
Replace varistor.
Replace transformer
Notes (1) It is not necessary to inspect
the dedicated cooling unit.
(2) Value in ( ) indicates
32,40models
(32, 40 model only)
Replace 23DH.
No
Outdoor fan does not
operate.
Check it during cooling
operation.
Check capacitor.
Replace fan motor.
Replace capacitor.
Abnormal
Yes
Normal
Check voltage with fan
connector.
Remove 52X
Β
(52X6)red
wires to check operation.
Short-circuit 63H to check
operation.
Measure voltage of 52XB
(52X6) No.
2 ,and terminal
block
2
.
Does not operate.
Does not operate.
Replace 63H.
Replace 52XB(52X6).
Operates
Operates
No
(1)
(1)
(1)
No