Lennox Core Unit Controller User Manual

5
Table 1. LED Operation Indicators
LED Status Indication Meaning
Heartbeat (HB)
(D33)
Green Slow Flash Normal Operation
Green Fast Flash Bootloader/rmwareupdatemode
No light Steady Off No voltage to M3 board or defective board
Green Steady On Unitinconguration/testmode(notinnormalmode)
S-BUS / PC
Connection (D70
and D71)
BUS (green)
Flickering
ON
Networktrafcpresent
TX (yellow)
Flickering
ON
Unit controller is transmitting
Thermostat Input Yellow
Indicates a
thermostat
demand
G - Blower on
W1 - First-Stage Heating
W2 - Second -Stage Heating
Y1 - First-Stage Cooling
Y2 - Second-Stage Cooling
OCP - Occupied
GLO - Global input
MODBUS Two LEDs that indicate transmit (TX) and receive (RX) activity.
Slow Flash = 1 second on; 1 second off.
Fast Flash = ½ second on; ½ second off.
A“ickering”LEDashessignicantlyfasterthana“fastash“.
NOTE: LEDs are energized by 24VAC thermostat inputs.
F. LOCAL INTERFACE - PUSH BUTTONS AND HEART BEAT
Figure 2. Push Buttons and Heart Beat
G. LOCAL INTERFACE - FOUR CHARACTER SEVEN
SEGMENT LED - STATUS CODES
Table 2. Status Codes
Status
Code
Denition
PnSt
Pre-Install
A173
Smoke
LoUt
Controller Lockout
Eror
Off On Alarm
d300
Delay up to 5 minutes
d020
Delay up to 20 seconds
dhUM
Dehumidication
ShEd
Compressor Load Shedding
Prht
Morning Warmup
Strt
Start up
FAh
Fresh Air Heating
Table 2. Status Codes
Status
Code
Denition
h050
Heating (50%)
PrCL
Pre-Cool
CEoP
Cool + Max Open Economizer
CE10
Cool + Modulate Economizer (10%)
FrCL
Free Cooling
FAC
Fresh Air Cooling
CO78
Cooling (78%)
671S
Blower On - (71.5%) OAS
623
Blower On (23%)
ioAS
No Demand - OAS
idLE
No Demand

Lennox Core Unit Controller Specifications

General

Brand	Lennox
Model	Core Unit Controller
Category	Controller
Language	English