Status Codes; Diagnostic Codes - Lennox G61MPV Service Manual

STATUS LED
DS3
ON / OFF '
DS6
CFM"
DS7
HI / LO"
DS8
HEAT"
Diagnostic LEDs are labeled DS1 and DS2. See figure 4 for location of diagnostic LEDs.
DS1
SIMULTANEOUS
SLOW FLASH
SIMULTANEOUS
FAST FLASH
SLOW FLASH
OFF
OFF
ALTERNATING
SLOW FLASH
SLOW FLASH
ON
ON
OFF
FAST FLASH
SLOW FLASH
ALTERNATING
FAST FLASH
NOTE − Slow flash rate equals 1 Hz (one flash per second). Fast flash rate equals 3 Hz (three flashes per second).
Low flame sense current = 0.17−0.22 microAmps.
TABLE 5

STATUS CODES

COLOR
DS3−ON indicates that the motor has a demand to operate. (This LED must be on in all
GREEN
modes).
DS6−blinking indicates the airflow (CFM) demand in the motor. The air flow is determine by
GREEN
counting blinks between two (2) second pauses. One blink equals approximatley 100 CFM.
DS7−ON indicaties the DS to R" jumper has not been cut. When the jumper is cut the system
will be operating with LENNOX HARMONY IIt (See Harmony Installation Instructions) or
YELLOW with the CCB1 Efficiency Plus control.
CCB1: When ON, a 24 VAC is being applied and when OFF, it has been removed. This on/off
operation varies the indoor blower's performance so dehumidification can be enhanced.
YELLOW DS8−ON indicates the system is in HEAT mode.
TABLE 6

DIAGNOSTIC CODES

DS2
Power on − Normal operation.
SIMULTANEOUS
Also signaled during cooling and continuous fan.
SLOW FLASH
SIMULTANEOUS
Normal operation − signaled when heating demand initiated at thermostat.
FAST FLASH
Primary, secondary, backup secondary or rollout limit switch open. Limits must
ON
close within 3 minutes or unit goes into 1 hour Watchguard.
Low prove switch open;
SLOW FLASH OR: Blocked inlet/exhaust vent;
OR: Low prove switch closed prior to activation of combustion air inducer.
High prove switch open;
FAST FLASH OR: Blocked inlet/exhaust vent;
OR: High prove switch closed prior to activation of combustion air inducer.
Watchguard −− burners failed to ignite; OR limit open more than 3 minutes;
ALTERNATING
OR lost flame sense 5 times in one heating cycle;
SLOW FLASH
OR pressure switch opened 5 times in one heating cycle.
OFF Flame sensed without gas valve energized.
ON
OFF
Circuit board failure or control wired incorrectly. Check 24 and 115 volts to board.
ON
SLOW FLASH Main power polarity reversed. Switch line and neutral.
FAST FLASH Low flame signal. Measures below 0.23 microAmps. Replace flame sense rod.
The following conditions are sensed during the ignitor warm−up period only:
1) Improper main ground;
ALTERNATING 2) Broken ignitor; OR: Open ignitor circuit;
3) Line voltage below 75 volts.
FAST FLASH
(If voltage lower than 75 volts prior to ignitor warm-up, control will signal waiting on
call from thermostat, and will not respond.
FUNCTION
DESCRIPTION
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