SERVICING
67
Honeywell Smart Valve Ignition Systems
NORMAL SEQUENCE OF OPERATION (Honeywell
Smart Valve System)
Testing Honeywell Smart Valve Systems
The ignition control module is a combination electronic and
electromechanical device and is not field repairable. Com-
plete unit must be replaced.
With Power ON:
WARNING
L
INE VOLTAGE NOW PRESENT.
Furnace thermostat calling for heat (4 to 5 second preheat
time).
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 "C & X terminals on control board.
3. Voltage Present - check for voltage (24 VAC) between
terminals 1 & 3 on gas valve (R-29 & GY-30). No voltage
- replace Control board.
Note:
Voltage to ignitor should read 24 volts.
4. Main burner will light only after pilot has proved flame. 30
seconds after main burner lights check for voltage be-
tween "heat" terminal and "neutral terminals" on board.
No voltage - replace Control board.
DSI Direct Spark Ignition Systems
NORMAL SEQUENCE OF OPERATION (DSI Direct
Spark Ignition System)
1. Thermostat calls for heat by energizing "W". The control
checks the pressure switch for open condition. If the pres-
sure switch is closed the control will flash code "3" and
wait for the pressure switch to open.
2. The induced draft motor is energized and the control
flashes code "2" and waits for the pressure switch to close.
Once the pressure switch is closed, the LED stops flash-
ing and the control begins timing the 15 second pre-purge.
3
2
1
6
5
4
9
8
7
12
11
10
L2
L2
L2
L2
COOL
HEAT
UNUSED
L1
L1
D1
FS
D
ia
g
n
o
s
tic
L
E
D
Blower Off Delay Settings
Transformer
speed up
DSI Control Board
3. The control energizes the spark igniter and gas valve for 7
seconds. If flame is established, the control goes into a
30 second heat on delay.
4. The indoor blower is energized at the heat speed after a
30 second on delay.
5. The control monitors the safety circuit inputs, flame, and
thermostat during operation.
6. When the thermostat is satisfied, the gas valve is de-
energized and the induced draft blower remains on for a
29 second post purge. The indoor blower remains on for
the selected heat blower off delay (90, 120, or 150 sec-
onds). Indoor blower off timing begins when thermostat
call for heat ends.
Testing Direct Spark Ignition (DSI) systems
Furnace 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. No
voltage - check 3 amp automotive type fuse on control
board. A blow fuse would indicate a short in the 24 volt
circuit (thermostat or limit circuit).
3. Voltage Present - check for voltage (24 VAC) between
terminals 1 & 3 on gas valve (R-29 & GY-30). No voltage
- replace Control board.
