High Pressure/Intermediate Pressure Fault 1 (Outdoor Unit) - Mitsubishi Electric PUHY-RP200 Service Handbook

[ IX Troubleshooting ]
1. Error Code
1302

High pressure/intermediate pressure fault 1 (outdoor unit)

2. Error definition and error detection method
1) If the pressure sensor reading exceeds 3.78 MPa (cooling) or 3.05 MPa (heating) or if the intermediate pressure sensor read-
ing exceeds 3.05 MPa (cooling)(first detection), outdoor unit will stop, go into the 3-minute restart delay mode, and automat-
ically restart after three minutes.
2) If the pressure sensor reading exceeds 3.78 MPa (cooling) or 3.05 MPa (heating) or if the intermediate pressure sensor read-
ing exceeds 3.05 MPa (cooling)(second detection), outdoor unit will stop again, go into the 3-minute restart delay mode, and
automatically restart after three minutes.
3) If the pressure sensor reading exceeds 3.87 MPa (cooling) or 3.29 MPa (heating) or the intermediate pressure sensor reading
exceeds 3.15 MPa (cooling) again (third detection) within 30 minutes of the second stoppage of the unit, the unit will come to
an abnormal stop, and the error code "1302" will appear on the display.
4) If the pressure of 3.78MPa [548psi] or higher is detected more than 30 minutes after the stop of the outdoor unit, the detection
is regarded as the first detection, and the operation described 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 sensor but also the pressure switch detects
+0,-0.15 +0,-22
4.15 MPa [601
7) Open phase due to unstable power supply voltage may cause the pressure switch to malfunction or cause the units to come
to an abnormal stop.
3. Cause, check method and remedy
(1) Indoor unit LEV2a, b actuation failure -> Cooling
Indoor unit LEV actuation failure -> Heating
(2) Closed refrigerant service valve
(3) Short cycle on the indoor unit side
(4) Clogged filter on the indoor unit
(5) Reduced air flow due to dirty fan on the indoor
unit fan
(6) Dirty heat exchanger of the indoor unit
(7) Indoor fan (including fan parts) failure or motor
failure
Rise in high pressure caused by lowered con-
densing capacity in heating operation for (2) - (7).
(8) Short cycle on the outdoor unit
(9) Dirty heat exchanger of the outdoor unit
(10) Outdoor fan (including fan parts) failure, motor
failure, or fan controller malfunction
Rise in discharge temp. by low pressure drawing
for (8) - (10).
(11) Solenoid valve (SV1a) malfunction (The by-pass
valve (SV1a) can not control rise in high pres-
sure).
(12) Thermistor failure (TH3, TH7)
(13) Pressure sensor failure
(14) Failure of the thermistor input circuit and pres-
sure sensor input circuit on the controller board
(15) Thermistor mounting problem (TH3, TH7)
(16) Disconnected male connector on the pressure
switch (63H1) or disconnected wire
(17) Voltage drop caused by unstable power supply
voltage
HWE10010
psi]
Cause Check method and remedy
Perform a cooling or heating operation to check the oper-
ation.
Cooling: Indoor unit LEV2a, b
Heating: Indoor unit LEV
Refer to the section on troubleshooting the
LEV.(page 228)
Confirm that the refrigerant service valve is fully open.
Check the indoor units for problems and correct them, if
any.
Check the outdoor units for problems and correct them, if
any.
Check the fan on the outdoor unit.
Refer to the section on troubleshooting the outdoor unit
fan.(page 227)
Refer to the section on troubleshooting the solenoid
valve.(page 226)
Check the thermistor resistor.(page 177)
Refer to the page on the troubleshooting of the high pres-
sure sensor. (page 224)
Check the temperature and the pressure of the sensor
with LED monitor.
Check the temperature and the pressure of the sensor
with LED monitor.
Check the input voltage at the power supply terminal block
(TB1).
- 157 - GB