General Troubleshooting; Error Codes - Lennox MCB Series Service Manual

2. General Troubleshooting

2.1. Error Codes

When the indoor unit encounters detects an error condition the running LED with flash in a corresponding series, the timer
LED may turn on or begin flashing and display the error code. These error codes are described in the following tables:
Table 1. Indoor Display Alert and Status Codes and Outdoor Unit LED
Unit Error Codes
Indoor unit EEPROM error
Indoor unit EEPROM parameter error
Communication error between indoor unit and outdoor units
Indoor fan speed error (DC motor)
Indoor room temperature sensor error (T1)
Indoor coil temperature sensor error (T2)
Refrigerant leakage detection (Cooling mode only)
Outdoor current overload protection
Outdoor ambient temperature sensor error (T4)
Outdoor coil temperature sensor error (T3)
Compressor discharge temperature sensor error (TP)
Outdoor unit EEPROM error
Outdoor unit fan speed error (DC fan motor)
Inverter module IPM error
High or Low voltage protection
Compressor drive error
Standby
Normal operation
Outdoor unit error
Communication error between main control board and display board
46F heat mode (Heat pumps models only)
Force Cooling
Remote or Wired controller Lock
Defrost (Heat pumps models only)
Active clean
Time On
Time Off
Anti-cold Air Flow (Heat pumps models only)
Remote On/Off
ECO mode
Outdoor Unit LED:
Slow flash: Flashing at 1Hz
Fast flash: Flashing at 2Hz
System Error Codes
Operational Status Codes
4
Outdoor Unit Main Indoor Unit
Control Board Display
MCB MWCB
n/a EH 00
n/a EH 0A
n/a EL 01
n/a EH 03
n/a EH 60
n/a EH 61
n/a EL 0C
n/a PC 08
n/a EC 53
n/a EC 52
n/a EC 54
n/a EC 51
n/a EC 07
n/a PC 00
n/a PC 01
n/a PC 04
SLOW FLASH n/a
LIT n/a
FAST FLASH n/a
n/a EH 0b
n/a FP
n/a FC
n/a LL
n/a dF
n/a CL
n/a On
n/a OF
n/a cF
n/a CP
On display 3
n/a
seconds
Solution
See "4.1. TS01-IDU" on
page 8.
See "4.3. TS02-S-INV" on
page 9.
See "4.4. TS04-S-IDU" on
page 10.
See "4.6. TS05-IDU" on
page 14.
See "4.8. TS06-INV" on
page 16.
See "4.10. TS08-S" on page
17.
See "4.7. TS05-ODU" on
page 15.
See "4.2. TS01-ODU" on
page 8.
See "4.5. TS04-S-ODU" on
page 13.
See "4.11. TS09-S" on page
18.
See "4.12. TS10-S" on page
19.
See "4.13. TS12-S" on page
20.
See "4.9. TS07" on page
16.