Service Manual

SERVICING
59
Status Light Equipment Status Check
On Normal Operation
Off
No Power or
Internal Control Fault
Check Input Power,
Check Fuse on Control,
Replace Control
1 Blink
Ignition Failure,
Open Rollout Switch,
or Open Aux. Limit
Switch
Check Gas Flow,
Check Gas Pressure,
Check Gas Valve,
Check Flame Sensor,
Check Flame Rollout,
Check Aux. Limit.
2 Blinks
Pressure Switch
Open
Check Pressure Switch
3 Blinks
Pressure Switch
Closed
Check Pressure Switch
4 Blinks
Open Main Limit
Switch
Main Limit Switch Open
5 Blinks False Flame Sensed Sticking Gas Valve
6 Blinks
Compressor Output
Delay
3 Minute Compressor
Anti-Cycle Timer
PCBAG123 Ignition Board Fault Codes
NOTE: The flash rate is 0.25 seconds on, 0.25 seconds
off, with a 2-second pause between codes.
3
2
1
6
54
9
8
7
12
11
10
L2 L2 L2
L2
COOL HEAT
UNUSED
L1
L1 D1
FS
Diagnostic LED
Blower Off Delay Settings
Transformer
speed up
PCBAG123 DSI Control Board
Testing Direct Spark Ignition (DSI) Systems
PCBAG127 Board
Heating Mode
Indoor thermostat calling for heat (15 second prepurge time
and 7 second trial for ignition).
1. Check for 230 volts from L1 terminal of control module to
L2. No voltage - check wire connections, continuity, etc.
2. Check for 24 volts at "R" to "C" thermostat terminals.
a. No voltage - check 3 amp automotive type fuse on
control board. A blown fuse could indicate a short
in the 24 volt circuit (thermostat or limit circuit).
b. Voltage Present - check limit and rollout (S-301
and S-302). If limit and rollout are closed, then
check for 24 VAC at the gas valve terminals.
c. No 24 VAC at gas valve - check 9 pin connector
and wires from ignition control to gas valve. If wires
and connections at 9 pin connector check good,
replace ignition control.
d. Voltage present at gas valve - replace gas valve.
LED
Flashes/Status
System Condition
Off
Internal Control Fault, Micro Controller
Detected Hardware Failure, or Gas Valve
Detected Energized When it Should be
De-energized
1 Lockout Due to Excessive Retries
2 Pressure Switch Stuck Open
3 Pressure Switch Stuck Closed
4 Open High Temperature Limit
5
Flame Present Outside the Flame
Detect Mode
6 Compressor Short Cycle Delay Active
7
Limit Opened Five Times within the
Same Call for Heat
8
Indoor Thermostat/Outdoor Thermostat
is Open
9
Pressure Switch/Loss of Charge Switch
is Open
Steady ON Normal
Red LED Fault Codes
LED
Flashes/Status
Flame Condition
2
Flame Present Outside the Flame Detect
Mode
1 Low Flame Signal Current
Steady ON Normal Flame
OFF No Flame Present
Amber LED Flame Status Codes