Error Code [1302] (At Startup); Error Code [1500] - Mitsubishi Electric HP120TNU-A Service Handbook

[7-3 Error Code Definitions and Solutions: Codes [1000 - 1999] ]
(21) Thermistor mounting problem (TH3, TH7)
(22) Disconnected male connector on the pressure switch (63H1) or
disconnected wire
(23) Open phase in the power-supply due to improper power-supply
wiring
7-3-4

Error Code [1302] (at startup)

1. Error code definition
High pressure fault 2 (Outdoor unit)
2. Error definition and error detection method
If the pressure of 0.098MPa [14psi] or lower is registered on the pressure sensor immediately before start-up, it will trigger an
abnormal stop, and error code "1302" will be displayed.
3. Cause, check method and remedy
(1) Inner pressure drop due to a leakage.
(2) Pressure sensor failure
(3) Shorted-circuited pressure sensor cable due to torn
outer rubber
(4) A pin on the male connector on the pressure sensor
is missing or contact failure
(5) Disconnected pressure sensor cable
(6) Failure of the pressure sensor input circuit on the
controller board
(7) Open phase in the power-supply due to improper
power-supply wiring
7-3-5

Error Code [1500]

1. Error code definition
Refrigerant overcharge
2. Error definition and error detection method
An error can be detected by the shell bottom superheat (TH15 - Te).
1) If the formula "compressor bottom SH (TH15 - Te) 10ºC [18ºF]" is satisfied during operation (first detection), the outdoor unit
stops, goes into the 3-minute restart mode, and starts up in three minutes.
2) If the formula "compressor bottom SH (TH15 - Te)
the outdoor unit (second detection), the unit comes to an abnormal stop, and the error code "1500" appears.
3) If the formula "compressor bottom SH (TH15 - Te)
the outdoor unit, the same sequence as Item 1) above (first detection) is followed.
4) For 40 minutes after the stop of the outdoor unit, preliminary errors will be displayed on the LED display.
5) If the formula "compressor bottom SH (TH15 - Te)
"compressor bottom SH (TH15 - Te)
1) above (first detection) is followed.
3. Cause, check method and remedy
(1) Overcharged refrigerant
(2) Thermistor input circuit failure on the control board
(3) Faulty mounting of thermistor (TH4, TH15)
HWE18220_GB
Cause
10ºC [18ºF]" is satisfied again within 40 minutes of the first stoppage of
10ºC [18ºF]" is satisfied 40 minutes or more after the first stoppage of
10ºC [18ºF]" is satisfied during the defrost operation and if the formula
10ºC [18ºF]" is also satisfied after the defrost operation, the same sequence as Item
Cause
Check the sensor temperature/pressure on the LED
monitor.
Refer to item (6) in section [6-1 Read before Test
Run].
Check method and remedy
Refer to the following page(s). [8-5-1 Comparing the
High-Pressure Sensor Measurement and Gauge
Pressure]
Refer to item (6) in section [6-1 Read before Test
Run].
Check method and remedy
Refer to the following page(s). [6-3 Evaluating and Adjust-
ing Refrigerant Charge]
Check the temperature and pressure readings on the sen-
sor that are displayed on the LED monitor.
Check the temperature and pressure readings on the
thermistor that are displayed on the LED monitor.
11
chapter 7 -