Engineering Mode For System Query; Engineering Mode Codes; Engineering Mode Error Codes - Lennox MCB Series Service Manual

2.3. Engineering Mode for System Query

• To enter engineer mode, in power-on or standby mode
and in non-locked state, using the wireless remote
control, press the key combination ON/OFF button and
FAN button for 7 seconds.
• After entering the engineer mode, the wireless remote
control will display the following icons (Auto, Cool, Dry,
Heat and the Battery) at the same time. In addition, will
also display the numeric code of the current engineer
mode (engineer mode startup mode will display
numeric code 0).
• In engineer mode, the value of the current numeric
code can be adjusted using the Up/Down button. The
ranges of codes are O to 30.
• To exit engineer mode, using the wireless remote
control, press the key combination ON/OFF button and
FAN button for 2 seconds.
• Engineering mode will automatically end if there is no
valid key operation for 60 seconds.

2.3.1. Engineering Mode Codes

Table 2. Engineering Mode Codes
Display Query Content
Code
0
Default start code that will be displayed when going into
engineering mode.
1
Room temperature
2 Indoor coil temperature
3 Outdoor coil temperature
4
Ambient temperature
5
Discharge temperature
6 Compressor Target Frequency FT
7
Compressor Running Frequency Fr
8
Unit Current dl
9 Outdoor AC Voltage Uo
10
Current indoor capacity test state Sn
11
Reserve
12 Set Speed Pr of the outdoor fan
13 Opening Lr of EEV
14
Actual Running Speed ir of the
indoor fan
15
Indoor Humidity Hu
16 Set Temperature TT after
compensation
17 - 19
Reserve
20 Indoor Target Frequency oT
21 - 30
Reserve
Description Coded Description
Indoor unit EEPROM error
Communication error between indoor unit and outdoor
units
T1 temperature
Indoor fan speed error (DC motor)
T2 temperature
Indoor room temperature sensor error (T1)
T3 temperature
Indoor coil temperature sensor error (T2)
T4 temperature
Refrigerant leakage detection (Cooling mode only)
TP temperature
Communication error between main control board and
Targeted Frequency
display board
Actual Frequency
Outdoor current overload protection
N/A
Outdoor ambient temperature sensor error (T4)
N/A
Outdoor coil temperature sensor error (T3)
N/A
Compressor discharge temperature sensor error (TP) or
sometimes referred to as (T5)
Outdoor unit EEPROM error
Outdoor fan
speed=value*8
Outdoor unit fan speed error (DC fan motor)
EXV opening angle-
Inverter module IPM error
value*8
High or Low voltage protection
Indoor fan
Outdoor low ambient temperature protection
speed=value*8
Compressor drive error
N/A
Outdoor ambient temperature too low
N/A
N/A
6
ON/OFF BUTTON
UP / DOWN BUTTON
FAN BUTTON

2.3.2. Engineering Mode Error Codes

Table 3. Engineering Mode Error Codes
Code
EH 00/EH 0A
EL 01
EH 03
EH 60
EH 61
EL 0C
EH 0b
PC 08
EC 53
EC 52
EC 54
EC 51
EC 07
PC 00
PC 01
PC 0L
PC 04
PC 0L