Table of Contents
Error Code
Description
P6/ L0-L9
IPM module protection
Table 31
When error codes L0-L9 appears occasionally, no action is necessary. The
system will restart automatically after 6 minutes. Please follow the steps
below if L0-L9 appears frequently.
P6/L0-L9 (IPM module protection)
Diagnosis
Check whether the
compressor wiring is normal
Yes
Check whether compressor
insulation resistance is greater
than 100KΩ
Yes
Check whether the resistance
of compressor U/V/W are
normal
Yes
Check whether there is the
same fault
Yes
Replace the board and
check whether there is the
same fault.
Yes
Replace the compressor and
check whether there is the
same fault.
Yes
Figure 52
Bosch 15 SEER2 Inverter Ducted Packaged Heat Pump - BTC 761701319 A (12.2022)
Handling
No
Reseat the wiring according
to wiring diagram
No
Replace the compressor
No
Replace the compressor
No
Keep running
No
Keep running
No
Keep running
Error Code
Description
AtL
Ambient Temperature Limited
Table 32
When the ambient temperature returns to within the
operating range, the system will recover automatically.
AtL (Ambient Temperature Limited)
Diagnosis
Check whether the ambient
temperature is beyond the range
cooling: 40°F-125°F
heating: 5°F-86°F
No
Check whether sensor T4 is
seated normally (T4 for Heat
Pump only)
Yes
Unplug the sensor, and check
whether the resistance of T4 is
within the operational range
(Refer to Table 36)
Yes
No action is necessary.
restart the system.
Figure 53
Error Code
Description
/
No display on control board
Table 33
No display on ODU control board
Diagnosis
Restart the system and check if
the LED display is working
No
Check if the high voltage
power supply is stable
Yes
Pull out the ODU motor
connection, check if there is
any display
No
Pull out the pressure
transducer connection,
check if there is any display
No
Replace ODU board
Figure 54
Installation Instructions
Handling
Yes
Normal
No
Reseat the sensor according
to the wiring diagram
No
Replace the faulty T3/T4
sensor
Handling
Yes
Working properly
No
Correct power supply
Yes
Replace ODU motor
Yes
Replace pressure
transducer
| 39
Table of Contents
Troubleshooting
