Lennox MHB Series User Manual

16
Service Information
Indoor Unit Alert Codes and Outdoor Unit LED
The following codes are display on the indoor unit LED on
the outdoor unit.
Table 9. Indoor Display Alert and Status Codes and
Outdoor Unit LED
Unit Error Codes
Outdoor Unit
Main Control
Board
Indoor
Unit
Display
System Error Codes
Indoor unit EEPROM error n/a EH 00
Indoor unit EEPROM parameter error n/a EH 0A
Communication error between indoor
unit and outdoor units
n/a EL 01
Indoor fan speed error (DC motor) n/a EH 03
Indoor room temperature sensor
error (T1)
n/a EH 60
Indoor coil temperature sensor error
(T2)
n/a EH 61
Refrigerant leakage detection
(Cooling mode only)
n/a EL 0C
Outdoor current overload protection n/a PC 08
Outdoor ambient temperature sensor
error (T4)
n/a EC 53
Outdoor coil temperature sensor
error (T3)
n/a EC 52
Compressor discharge temperature
sensor error (T5)
n/a EC 54
Outdoor unit EEPROM error n/a EC 51
Outdoor unit fan speed error (DC fan
motor)
n/a EC 07
Inverter module IPM error n/a PC 00
High or Low voltage protection n/a PC 01
Outdoor low ambient temperature
protection
n/a PC 0L
Compressor drive error n/a PC 04
Standby SLOW FLASH n/a
Normal operation LIT n/a
Outdoor unit error FAST FLASH n/a
Communication error between main
control board and display board
n/a EH 0b
Operational Status Codes
46F heat mode n/a FP
Force Cooling n/a FC
Remote or Wired controller Lock n/a LL
Defrost n/a dF
Active clean n/a CL
Time On n/a On
Time Off n/a OF
Anti-cold Air Flow n/a cF
Remote On/Off n/a CP
ECO mode n/a
On display
3 seconds
Outdoor Unit LED:
Slow ash: Flashing at 1Hz
Fast ash: Flashing at 2Hz
Test Run
Pre-Checks
Only perform test run after you have completed the
following steps:
• Electrical Safety Checks – Conrm that the unit’s
electrical system is safe and operating properly.
• Refrigerant Leak Checks – Check all are nut connec-
tions and conrm that the system is not leaking.
• Conrm that suction and liquid valves are fully open.
Procedure
You should perform the Test Run for at least 30 minutes.
1. Connect power to the unit.
2. Press the ON/OFF button on the remote controller to
turn it on.
3. Let each function run for 5 minutes, and perform the
following checks:
Table 10. Test Run Checklist
Checks Pass Fail
No electrical leakage
Unit is properly grounded
All electrical terminals properly
covered
Indoor and outdoor units are solidly
installed
All pipe connection points do not leak
Water drains properly from drain hose
All piping is properly insulated
Unit performs COOL function properly
Indoor unit louvers rotate properly
Indoor unit responds to wireless
remote
Double-Check Line Set Connections
During operation, the pressure of the refrigerant circuit
will increase. This may reveal leaks that were not present
during your initial leak check. Take time during the Test
Run to double-check refrigerant line set connections and
verify there are no leaks.
1. Using the wireless remote control, return unit to the
normal operating temperature.
2. Using insulation tape, wrap the indoor refrigerant pipe
connections that you left uncovered during the indoor
unit installation process.

Lennox MHB Series Specifications

General

Brand	Lennox
Model	MHB Series
Category	Air Conditioner
Language	English