Lennox MS8 SERIES Installation And Service Procedures page 60

Continued — 09 through 12 and 30 kBtu System Status and Error Codes — Indoor Character Display and Outdoor LEDs
Outdoor LED Displays
Indoor
(number of blinks)
Character
Display
Yellow Red
H4 6 OFF
H5 4 OFF
H6 OFF OFF
LP 16 OFF
L3 OFF 14
L9 9 OFF
PH 13 OFF
PL 12 OFF
MS8C / MS8H (208-230V)
Error Description
Green
Compressor high
OFF temperature
protection
Intelligent Power
Module (IPM)
OFF
module protection
Indoor fan not
OFF
communicating
Indoor and outdoor
OFF
unit mismatch
Outdoor DC fan
OFF
motor malfunction
Power factor
OFF
protection
High voltage protec­
OFF
tion
Low voltage protec­
OFF
tion
Page 60
System Status
All system functions are
terminated except indoor fan.
All system functions are terminated.
All system functions are
terminated.
All system functions are
terminated.
Troubleshooting for Possible
Causes
S Check for proper wiring connec­
tions and loose wires at outdoor
control (CT1, 2) input plug.
S Check for continuity across over­
load protection sensor terminals
mounted at top of compressor.
This can be caused by any of the fol­
lowing:
S Loss of cooling to the heat sink
S Low voltage.
S High ambient temperature
S Loose screws fastening the outdoor
control to the heat sink
See unit information manual for further
information.
Possible Indoor control failure or in­
door motor failure.
S Check wiring between fan motor
and indoor control.
S Check wiring between fan motor
and terminal marked OFFAN.
S Replace one or both, if necessary.
The two system components are
mis-matched. Refer to engineering
handbook for correct match-up. Also,
verify that the red jumper is in place
on the indoor control board.
S Check wiring between fan motor
and outdoor control terminal
marked OFFAN.
S If wiring is correct, replace outdoor
DC fan motor.
Indoor unit is experiencing either a
high or low input voltage condition.
S Verify proper input voltage at
terminal strip N(1) and 3.
S Check input voltage on outdoor unit
terminal strip (N and L terminals).
S If voltage is higher than 265VAC,
disconnect power to unit. Correct
input voltage problem before reap­
plying power to system.
S If voltage is below 265VAC, then
check capacitor while unit is turned
off.
S If voltage is between 200-208V, ca­
pacitor is working properly
S If voltage is some other value, re­
place capacitor.
S If input voltage and capacitor are
normal, replace outdoor control.
S Check input voltage on outdoor unit
terminal strip (N and L terminals).
S If voltage is lower than 150VAC,
restart system and check power
again.
S 9 - 12 kBtu, 208-230VAC systems
only -- Check reactor (choke) line
connection on outdoor control
terminal marked AC-L2.