Mitsubishi MSH-18RV User Manual

56
MSH-24/30RV
• The following indication does not depend on the shape of lamp.
Operation Indicator
flashing
Before taking measures, make sure that the symptom reappears, for accurate troubleshooting.
Self check table
NOTE : When the indoor unit has started operation and the above detection method has detected an abnormality (the first
detection after the power ON), the indoor electronic control P.C. board turns OFF the indoor fan motor with the
OPERATION INDICATOR lamp flashing.
No.
1
2
4
5
6
SymptomOperation indicator lamp Detection method
Checkpoint
0.5-second ON
0.5-second OFF
1-time flash
2.5-second OFF
Mis-Wiring
Serial sig-
nal
MSH-24RV
Outdoor
thermistor
Outdoor
control
system
Indoor coil
thermistor
3 minutes after power supply turns ON, when
serial signal is not received.
When serial signal from outdoor unit stops for
4 to 5 seconds.
<Thermistor short>
Thermistors are abnormal when they short
after compressor start-up.
<Thermistor open>
Thermistors are abnormal when they open
after compressor start-up.
However, discharge temperature thermistor is
abnormal when open circuit is detected more
than 10 minutes after compressor start-up.
When it cannot properly read data in the
nonvolatile memory of the deicer P.C. board,
outdoor unit stops [and restarts 3 minutes
later(MSH-24RV).]
• Shortage of refrigerant
• Replace the deicer P.C.
board.
Refer to J "Check of outdoor
thermistor" on page 66.
• Replace the deicer P.C.
board.
• Refer to H "How to check
mis-wiring " on page 65.
• Refer to G "How to check
mis-wiring and serial signal
error" on page 64.
3
Indoor fan
motor
7
Low
discharge
temperature
protection
MSH-30RV
When discharge temperature has been 50:
or less on cool operation, or has been 49: or
less on heat operation for 20 minutes.
Abnormal
point
Outdoor unit
does not
operate.
Room
tempera-
ture
thermistor
2-time flash
2.5-second OFF
Detect Indoor coil/room temperature
thermistor short or open circuit every 8
seconds during operation.
• Refer to the characteristics of
main indoor coil thermistor,
sub indoor coil thermistor,
and room temperature
thermistor on page 67 or 68.
3-time flash
2.5-second OFF
Indoor fan
repeats 12
seconds ON
and 3
minutes
OFF.
When the
indoor fan
breaks, the
fan keeps
stopping.
When rotational frequency feedback signal is
not emitting during 12-second indoor fan
operation.
• Refer to A "Check of
indoor fan motor" on page 59.
4-time flash
2.5-second OFF
Indoor
control
system
MSH-30RV
When it cannot properly read data in the
nonvolatile memory of the indoor electronic
control P.C. board.
Outdoor unit
does not
operate.
Outdoor unit
does not
operate.
• Replace the indoor electronic
control P.C. board.
6-time flash
2.5-second OFF
• Refer to I "Check of LEV" on
page 66.
• Check refrigerant circuit and
refrigerant amount.
Outdoor unit
does not
operate.
Outdoor unit
does not
operate.
Outdoor unit
does not
operate.
7-time flash
2.5-second OFF
10-time flash
2.5-second OFF
· Flashing of the OPERATION INDICATOR lamp (on the left-hand side) indicates possible
abnormalities.
· The OPERATION INDICATOR lamp (on the left-hand side) is lighting during normal operation.
OB272-2.qxp 02.1.26 1:23 PM Page 56

Mitsubishi MSH-18RV Specifications

General

Brand	Mitsubishi
Model	MSH-18RV
Category	Air Conditioner
Language	English