Daikin APGM3 Service And Troubleshooting page 40

SERVICING
Testing Direct Spark Ignition (DSI) systems
Thermostat calling for heat (15 second pre-purge time and
7 second trial for ignition).
1. Check for 230 VAC from L1 terminal of control module
to L2. No voltage - check wire connections, continuity,
etc.
2. Check for 24 VAC at "R" to "C" thermostat terminals.
a. No voltage - check 3 amp automotive type fuse
on control board. A blown fuse would indicate a
short in the 24 VAC circuit (thermostat or limit
circuit).
b. Voltage Present - check limit, auxiliary limit
and rollout. If limit, auxiliary limit and rollout are
closed, then check for 24 VAC at the gas valve
terminals.
No 24 VAC at gas valve - replace Control board.
PCBAG123 Ignition Board Fault Codes
Status Light Equipment Status
On Normal Operation
No Power or
Off
Internal Control Fault
Ignition Failure,
Open Rollout Switch,
1 Blink
or Open Aux. Limit
Switch
Pressure Switch
2 Blinks
Open
Pressure Switch
3 Blinks
Closed
Open Main Limit
4 Blinks
Switch
5 Blinks False Flame Sensed
Compressor Output
6 Blinks
Delay
NOTE: The flash rate is 0.25 seconds on, 0.25 seconds
off, with a 2-second pause between codes.
Check
Check Input Power,
Check Fuse on Control,
Replace Control
Check Gas Flow,
Check Gas Pressure,
Check Gas Valve,
Check Flame Sensor,
Check Flame Rollout,
Check Aux. Limit.
Check Pressure Switch
Check Pressure Switch
Main Limit Switch Open
Sticking Gas Valve
3 Minute Compressor
Anti-Cycle Timer
L2 L2 L2 L2
L1
COOL HEAT L1
UNUSED
PCBAG123 DSI Control Board
Testing Direct Spark Ignition (DSI) Systems
PCBAG127 Board
Heating Mode
Indoor thermostat calling for heat (15 second pre-purge
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. 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.
Blower Off Delay Settings
1
3 2
6 5 4
9 8 7
FS
D1
12 11 10
Transformer
speed up
40