Honeywell S8700 Series, Installation Instructions Manual

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S8700B,D-F,J-M DIRECT SPARK IGNITION CONTROLS
69-1299 6
— Make certain that the S8700 is not in safety lockout.
De-energize the system by moving the temperature
control setpoint below the room temperature or
remove power to the S8700 control. Wait at least five
seconds and reenergize the system by moving the
temperature control setpoint 5
°
F (3
°
C) above the
room temperature. Reapply 24 Vac power to the
S8700 control.
— Check the ceramic insulator on the flame sensor,
spark igniter or igniter/sensor. A cracked insulator
allows current to leak to ground. Replace the device
if the insulator is cracked.
— Check the flame sensor and its mounting bracket.
Flame sensor must be held firmly in place and be
positioned in the most flame per the appliance
manufacturer specifications. Repair or replace as
necessary. Correct the position if it is bent out of
shape.
— Review the S8700 normal sequence of operation.
See the Start System section.
S8700 COMPONENT CHECKS
Spark Ignition Circuit
The S8700 provides high voltage spark energy to light
the main burner. To check the spark ignition circuit, do
the following:
1. Shut off the gas supply to the gas control.
2. Be sure system power supply delivers proper volt-
age to the S8700 during the ignition cycle.
3. Disconnect the ignition cable at the S8700 spark
terminals to isolate the circuit from the spark igniter
or igniter sensor. Prepare a short jumper lead,
using heavily insulated wire such as ignition cable.
Fig. 4. S8700B,D,J,K one-trial sequence of operation.
CALL FOR HEAT (24 VAC INPUT TO 24 VAC TERMINAL).
SAFE START CHECK. FLAME DETECTED?
(LED BLINKS RAPIDLY).
PREPURGE (J AND K MODELS)
SPARK GENERATOR POWERED; MAIN VALVE OPENS.
MAIN BURNER LIGHTS AND FLAME SENSED
DURING TRIAL FOR IGNITION?
NORMAL MAIN BURNER OPERATION.
FLAME SIGNAL LOST?
CALL FOR HEAT ENDS (24 VAC INPUT REMOVED
FROM 24 VAC TERMINAL).
MAIN BURNER OFF.
MAIN VALVE STAYS OPEN;
SPARK GENERATOR POWERED.
START
SAFE START
CHECK/
PREPURGE
TRIAL FOR
IGNITION
MAIN
BURNER
OPERATION
END
NO NO
NO
YES
NO
YES
YES
NO
YES
M16529
WAIT 4 SEC. FLAME
STILL DETECTED?
YES
LOCKOUT WITH
LED ON STEADY.
MAIN VALVE CLOSES;
SPARK GENERATOR OFF.
LOCKOUT WITH LED ON STEADY.
MAIN BURNER LIGHTS AND FLAME
SENSED DURING TRIAL FOR IGNITION?
NOTES:
— WHEN CONTROL IS IN LOCKOUT, ALARM OUTPUT (IF PROVIDED) IS ENERGIZED.
— LED FLASHES AT HEARTBEAT SPEED DURING ALL NORMAL OPERATION.