32
Diagnostic Chart
LED Indications: Flash Codes
LED Activity
Description
Color
Comments
OFF No LED Activity
No 24 VAC
Power to control
Red, Amber, Green
Power -up verification of LED
Steady ON
Control Fault Detected Hard
Lock
RED
Rapid Flash
Reversed Line Voltage Polarity
RED
No CFH required.
1 Flash
System Lockout - Retries
Exceeded
RED
Retries are defined as failed ignition attempts,
i.e. no flame sense during the trial for ignition
period. Recycles are defined as loss of flame
after flame has been established during the
trial for ignition period, and there is no limit to
the number of recycles.
2 Flashes
Pressure Sensor Null Error:
Inconsistent reading with
inducer off
RED
Control waits 5 seconds after CFH before
displaying fault. Fault is displayed until fault
condition corrects or CFH is removed.
3 Flashes
Pressure Sensor Span Error:
Inconsistent reading with
inducer on
RED
Span test maximum duration is 90 seconds.
Once the span test fails, the control continues
to attempt to start furnace and fault is
displayed until fault condition corrects or CFH
is removed.
4 Flashes
High Limit Switch Open
RED
When an open limit is detected, the control
energizes the blower at cooling speed and the
inducer at the RUN setting - no CFH required.
Once the limit closes and the CFH is present,
the furnace returns to normal operation. Three
limit events in a single CFH results in a 1 hour
lockout.
5 Flashes
Flame Present with
Gas Valve OFF
RED
When detected, the control energizes the
inducer at the "Run" setting, energize the
blower on Heat speed, and displays fault - no
CFH required. Control continues normal
operation when fault condition is corrected.
6 Flashes
Auxiliary Limit Open
RED
When detected, the control energizes the
inducer a maximum speed, the blower at
cooling speed and displays fault - no CFH
required. Control continues normal operation
when fault condition is corrected.
7 Flashes
Gas Valve Circuit Shorted
RED
Voltage sensed at the gas valve terminal with
the safety relay in the de-energized state. The
inducer is energized to maximum speed.
Lockout Notes
Power cycle will
reset all
lockout timers
N/A
N/A
Continuous Reset Cycle Power
30 seconds
5 minute lockout
5 minute lockout
Operation continues after fault
correction
1 Hour Fixed
5 second lockout Unlimited
Retries
5 minute lockout Unlimited
Retries
5 minute lockout
1 hour lockout after three
faults in a single CFH
5 minute lockout
