Mitsubishi Electric CITY MULTI PUHY-P108 Service Handbook page 282

Error definition and error
Error Code
detection method
1302 Abnormal high 1. If the pressure of
pressure 1 3.87MPa[561psi] or
(outdoor unit) higher is detected by
the pressure sensor
during operation (the
first detection), the
outdoor stops once,
turns to anti-restart
mode for 3 minutes,
and restarts after 3
minutes automatically.
2. If the pressure of
3.87MP[561psi] or
higher is detected by
the pressure sensor
again (the second de-
tection) within 30 min-
utes after the first stop
of the outdoor unit, the
outdoor unit stops
once, turns to anti-re-
start mode for 3 min-
utes, and restarts after
3 minutes automati-
cally.
3. If the pressure of
3.87MP[561psi]a or
higher is detected by
the pressure sensor
(the third detection)
within 30 minutes of
the second stop of the
outdoor unit, the out-
door unit will make an
error stop, and the er-
ror code "1302" will be
displayed.
4. If the pressure of
3.87MPa[561psi] or
higher is detected
more than 30 minutes
after the stop of the
outdoor unit, the de-
tection is regarded as
the first detection, and
the operation de-
scribed in step 1
above will start.
5. For 30 minutes after
the stop of the outdoor
unit, preliminary errors
will be displayed on
the LED display.
6. The outdoor unit
makes an error stop
immediately when not
only the pressure sen-
sor but also the pres-
sure switch detects
4.15
[601
(1) LEV failure on the indoor
unit
(2) BC controller LEV mal-
function
Heating only or heating
main : Indoor LEV 3
Defrost : LEV3
(3) BC controller SVM1 and 2 mal-
function
->Cooling only or defrost
(4) BC controller SVA malfunction
->Cooling only or cooling main
(5) BC controller SVB malfunction
->Heating only or heating main
(6) Solenoid valve SV malfunction
(4a-4d (P72-P144 models) ,4a-
4d and 5a, 5b (P168-
P234models)): heating only,
heating main
->Heating only or heating main
(7) Port address setting error.
(8) Closed ball valve
(9) Short cycle on the indoor unit
side
(10) Clogged filter on the indoor unit
(11) Reduced air flow due to dirty
fan on the indoor unit fan
(12) Dirty heat exchanger of the in-
door unit
(13) Indoor fan (including fan parts)
failure or motor failure
For (9) - (13), rise in high pres-
sure caused by lowered con-
densing capacity in heating only
or heating main operation.
(14) Short cycle on the out-
door unit
(15) Dirty heat exchanger of
the outdoor unit"
(16) Outdoor fan (including fan
parts) failure, motor failure, or
fan controller malfunction
-> Heating only or heating main
Rise in discharge temp. by low
pressure drawing for (13) - (15).
(17) Rise in high pressure cannot be
controlled due to solenoid valve
SV1 malfunction.
(18) Thermistor failure
(TH5 - TH7)
(19) Pressure sensor failure
(20) Failure of the thermistor input
circuit and pressure sensor in-
put circuit on the controller
board
(21) Faulty mounting of ther-
mistor (TH5 - TH7)
+0,-0.15
MPa
(22) Disconnected male connector
+0,-22
psi]
on the pressure switch (63H) or
disconnected wire
- 273 -
Cause Check method and remedy
Perform a heating operation and
check the operation.
Cooling: LEV on the indoor unit
LEV1,2,3
SVM1,2
SVA
Heating: LEV on the indoor unit
LEV3
SVM2
SVB
SV4a - 4d
SV5a,5b
Refer to the page on trouble-
shooting for LEV and solenoid
valve.
Confirm the port address of the indoor unit.
Confirm that the ball valve is fully open.
Check the indoor units for problems
and correct them, if any.
Check the fan on the outdoor unit.
Refer to the section on troubleshoot-
ing the outdoor unit fan.
Refer to the section on troubleshoot-
ing the solenoid valve.
Check the thermistor resistor.
Refer to the page on the trouble-
shooting of the high pressure sen-
sor.
Check the temperature on the LED monitor
and check for contact failure of the connec-
tor.
[ IX Troubleshooting ]