69-0669B—2
2
Fig. 1—Mounting R8991 on main burner
housing.
HINGE
SCREWS (2)
HOLDING
SCREWS (2)
RESET
BUTTON
R8991
OIL PRIMARY
CONTROL
HINGE
BURNER
HOUSING
M5245
TO
COMBUSTION
CHAMBER
1
THERMOSTAT
SCREW
TERMINALS
WIRING ENCLOSURE
AREA AT REAR
OF BURNER HOUSING
1
MEANS OF SECURING R8991 TO BURNER
HOUSING VARIES DEPENDING ON R8991 MODEL USED.
1
CLIPS
2. Make line voltage connections as shown in Fig. 2.
Connect orange wire to burner motor, white wire to line
voltage-neutral, and black wire to line voltage-hot.
3. Splice leads with solderless connectors.
4. Do not exceed load ratings listed in the Application
section.
When the line voltage wiring is completed, secure the
R8991 control to the burner housing on the side opposite of
the hinge (see Fig. 1).
24V THERMOSTAT WIRING CONNECTIONS
Run low voltage wiring from the thermostat to the R8991
location. Connect thermostat wires to thermostat screw ter-
minals (T1 and T2) on R8991. Thermostat screw terminals
are accessible on the R8991 cover (see Fig. 1).
LINE VOLTAGE CONTROLLER WIRING
CONNECTIONS
Jumper T1–T2 terminals on R8991 and connect line volt
thermostat in series with limit controller.
Fig. 2—Typical wiring diagram of R8991 for oil
burner system.
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND
OVERLOAD PROTECTION AS REQUIRED.
2 FOR USE WITH LINE VOLT CONTROLLER, JUMPER
T-T TERMINALS AND CONNECT LINE VOLT
THERMOSTAT IN SERIES WITH LIMIT CONTROLLER.
WIRING CODE
LOW VOLTAGE
LINE VOLTAGE
LINE VOLT
THERMOSTAT
(IF USED)
BLACK
WHITE
ORANGE
L1
(HOT)
L2
(LINE)
24V THERMOSTAT
1
2
2
M814
LIMIT
BURNER
MOTOR
OIL
VALVE
T
T
R8991
TYPICAL R8991 CONTROL CIRCUIT
Operation
R8991 Interrupted Ignition Recycle Oil Primary and
Ignitor operation is discussed in Table 1.
The R8991 Primary and Ignitor is controlled by a small
computer. This computer determines the appropriate times
to use the five second continuous spark and when to use the
duty-cycled spark. By selecting the appropriate 32 kHz
spark, the computer decreases wear on the components and
significantly extends the life of the R8991 Primary and
Ignitor beyond that of conventional iron core primaries.
The R8991 Interrupted Ignition Recycle Oil Primary and
Ignitor may not produce a five-second continuous spark on
installation startup. The ignition spark will probably be at a
20% duty cycle of 5 Hz (spark on for 0.04 second and off
for 0.16 second).
Because the duty-cycled spark has a one-to-four on-off
cycle, it may sound like it is pulsing. This is normal and will
not affect the operation of the primary or the burner. The
duty-cycled spark will ignite the oil and the normal cycle will
proceed through Ignition Carryover and Run.
The duty-cycled spark will ignite the oil even under ad-
verse conditions such as cold oil, contaminated oil, excess
air, or fouled electrodes. By pulsing the spark, ignitor and
electrode life is extended, because the components are ener-
gized for less time and do not heat up as much as components
would in a continuous spark system.
Table 1 describes R8991 operation.
