69-0669B—2
4
3. Check indicator light. If light is on, stray light is falling
on the cad cell or the cad cell is shorted. Correct the problem
to ensure that the light is off before proceeding to the next
step.
4. Open hand valve in oil supply line.
5. Set limit control, and set thermostat to call for heat or
jumper T1-T2 terminals on R8991 to call for heat.
6. After a one second delay, oil burner and ignitor should
turn on.
7. If oil primary control locks out before fuel reaches
burner, push in and release red reset button. The oil burner
should start again after a short delay.
8. Reset R8991 until fuel reaches burner and lights off.
When the burner lights off, the R8991 indicator light should
be on. Do not continuously hold in reset button. The R8991
must sense that reset switch contacts are open and then
closed to allow the control to reset. This prevents a short in
the switch from bypassing the manual reset requirement.
CHECK SAFETY FEATURES
Simulate flame failure:
1. Turn on the main burner by following the starting
procedure.
2. Close hand valve in oil supply line.
3. Observe that oil burner should shut off after oil in
supply line is all used. Oil primary control goes into recycle.
The indicator light flashes at 1/4 Hz (2 seconds on, 2 sec-
onds off). After 60 second recycle time, another trial for
ignition begins and flashing stops.
4. Observe that oil primary control should lock out within
timing indicated on label. Indicator light should be flashing
at 2 Hz (1/4 second on, 1/4 second off). Ignition and burner
should stop.
Simulate power failure:
1. Turn on the main burner by following the starting
procedure.
2. Disconnect power by switching breaker or removing
fuse. Main burner should shut off.
3. Reconnect power by switching breaker or replacing
fuse. Main burner should turn on after one second.
If the system does not operate as described, proceed to
the Troubleshooting section.
NOTE: The R8991 locks out when eight consecutive trials
for ignition are initiated but not completed (thermostat
closes for less than the lockout time and oil does not
ignite). This prevents an intermittent signal at the thermo-
stat terminals from indefinitely cycling the relay and
restarting the lockout timing.
Troubleshooting
IMPORTANT: Only a trained, experienced service techni-
cian should perform the troubleshooting procedure.
To completely troubleshoot an oil burner installation,
check the burner and oil primary control (which includes
ignition source and cad cell) for proper operation and
condition.
The indicator light on the oil primary control provides
lockout, recycle, and cad cell indication as follows:
Flashing at 2 Hz (1/4 second on, 1/4 second off): System
is locked out.
Flashing at 1/4 Hz (2 seconds on, 2 seconds off): Control
is in the recycle mode.
On: Cad cell is sensing flame.
Off: Cad cell is not sensing flame.
PRELIMINARY STEPS
CAUTION
To prevent damage to the R8991, do not use an
ignition tester to check out the R8991 Ignition
Source. Iron core transformer ignition testers can
damage solid state ignitors.
CAUTION
When using R8991 with a 24V thermostat, dis-
connect at least one lead wire from the T1-T2 ter-
minals on R8991 before jumpering T1-T2 to
simulate a call for heat or damage to thermostat
heat anticipator can result.
Before checking the R8991, perform these preliminary
checks (repair or replace controls as necessary):
• Check the power supply, all wiring connections, and
burner motor fuse. Assure power is turned on to all
controls and burner motor.
• Check the limit switch for proper operation.
• Check the electrode gap and position.
• Check contacts between the R8991 and the electrodes.
• Check the oil pump pressure.
• Check the piping to the oil tank.
• Check the oil nozzle, oil supply, and oil filter.
CHECK OIL PRIMARY CONTROL AND IGNITOR
If the trouble does not seem to be in the burner or
ignition hardware, check the oil primary control and the
ignitor by using the following equipment:
• Screwdriver.
• Voltmeter (0 to 150 Vac).
• Insulated jumper wires with both ends stripped.
CAUTION
Troubleshooting is done with the system powered.
Be careful to observe all necessary precautions to
prevent electrical shock or equipment damage.
BURNER MOTOR DOES NOT START WHEN
THERMOSTAT CALLS FOR HEAT
Preliminary Checks
1. Make sure limit switches are closed and contacts are
clean.
2. Check for line voltage power at the oil primary con-
trol. With thermostat calling for heat, voltage should be
120 Vac between black and white lead wires on oil primary
control.
