Start System - Honeywell S8700 Series Installation Instructions Manual

S8700B,D-F,J-M DIRECT SPARK IGNITION CONTROLS
2
S8700E,J,L CONTROL
GND
VALVE (GND)
24 Vac (GND)
24 Vac
BURNER
3
TEMPERATURE
CONTOL
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS
AND OVERLOAD PROTECTION AS REQUIRED.
2
ALTERNATE LIMIT CONTROLLER LOCATION.
3
MAXIMUM IGNITER-SENSOR CABLE LENGTH: 6 FT (1.8 M).
Fig. 3. Typical wiring diagram for
S8700E,J,L single rod models.
NOTE: NOTE: Proper system operation requires that
the S8700 GND (Burner) terminal is wired to
be electrically common with the spark
electrode bracket, flame sensor bracket (if a
separate flame sensor is used) and the main
burner. In many applications, this is
accomplished through connecting the S8700
GND (Burner) terminal to the appliance
chassis, as the other noted components are
presumed to be electrically common with the
appliance chassis. If flame sensing problems
are noted, it may be due to corroded or loose
electrical connections between the noted
components and the appliance chassis.
STARTUP
The following start-up procedures are basic to all S8700
controls. If this is a replacement application, refer to the
specific instructions provided by the heating appliance
manufacturer, if available. Also, since the auxiliary
controls used on any DSI system can differ, refer to the
manufacturer's instructions for start-up and checkout
procedures for other system components.
NOTE: If the S8700 does not perform as outlined in
the following Start System and Check Trial for
Ignition steps, refer to the Service section to
determine the cause.
69-1299
LIMIT CONTROLLER
TRANSFORMER
FLAME
SENSE
ALARM, IF USED
ALARM
VALVE
ANY COMBINATION
GAS CONTROL
(GND)
2.0A MAX.
SPARK
Q347
SPARK
IGNITER
BURNER
IGNITER AND
BURNER GROUND
Gas Leak Test
If the gas control has been replaced as a part of the S8700
L1
(HOT)
installation, perform the following test for gas leaks.
L2
1
WARNING
Explosion or Fire Hazard.
Gas Leaks can cause property damage,
severe injury or death.
To avoid possible explosion or fire, perform the
Gas Leak Test.
With the main burner in operation, paint the pipe joints
and valve gasket with a rich soap and water solution.
Bubbles indicate a gas leak. To stop a leak, tighten the
joints and screws. Never use a flame to check for gas
leaks.

Start System

1. Turn on the power and the gas supply.
2. Set the temperature control to call for heat and
watch for a spark at the igniter (S8700B,D,E,F
models have no delay on start-up; S8700J,K,L,M
models have a predetermined delay on start-up
for prepurge).Check that the system starts as
follows: Prepurge delay (if provided), spark turns
on, gas valve opens at once and burner ignites
after gas reaches the main burner. Once the
M16528
burner flame is established, spark igniter cuts off.
NOTE: NOTE: If the gas control has been replaced or
serviced, lightoff may not be satisfactory until
air has been purged from the gas line or the
gas input and combustion air have been
adjusted (see manufacturer's instructions).
Table 3. S8700 Trial for Ignition Periods.
Specified Trial for
Ignition (TFI) (stamped
on control)
4.6 sec
6.6 sec
11.1 sec
21.1 sec
Check Trial for Ignition
1. Check device label on the control to determine
the correct trial for ignition time.
2. With the system power off and the thermostat or
temperature control set to call for heat, manually
shut off the gas supply.
3. Turn power on to energize the S8700 and
immediately start timing when the gas valve is
energized.
4. Determine the number of seconds to drop-out of
the gas valve. It should not exceed the trial for
ignition time shown in Table 5.
5. After spark cutoff, manually reopen the gas sup-
ply cock. No gas should flow to the main burner.
6. Reset the system as described in Resetting
S8700 After Safety Lockout section.
4
Trial for Ignition Should
Not Exceed
5.0 sec
7.0 sec
11.5 sec
21.5 sec