Honeywell R8991 Manuel page 5

Procedure
1. Check indicator light with burner
off.
2. Jumper thermostat (T1-T2)
terminals at oil primary control.
3. Shield cad cell from external light. 3. Eliminate external light source or
Burner starts then locks out on safety with indicator light flashing at 2 Hz (1/4 second on, 1/4 second off)
1. Reset oil primary control by
pushing in and releasing red reset
button. Indicator light will stop
a
flashing.
2. Listen for spark after burner turns
on.
3. Check indicator light after flame is
established, but before oil primary
control locks out.
4a. Disconnect line voltage power
and open line switch.
4b. Unplug cad cell and clean cad
cell face with soft cloth. Check
sighting for clear view of flame.
Replace cad cell in socket.
4c. Reconnect line voltage power and
close line switch. Jumper
thermostat (T1–T2) terminals to
start burner.
5a. Disconnect line voltage power and
open line switch.
5b. Remove existing cad cell and
replace with new cad cell (part
no. 130367).
5c. Disconnect all wires from
thermostat terminals to ensure
that there is no call for heat.
Reconnect line voltage power
and close line switch.
5d. Expose new cad cell to bright light
such as a flashlight.
6. Cut yellow lead wires near cad cell
bracket and short lead wires.
a
There are several internal failures that cause the R8991 to remain in lockout for safety. If indicator light continues to
flash at 2 Hz (1/4 second on, 1/4 second off) after resetting control, replace R8991.
1. Indicator light is on. Cad cell is seeing
external light or is defective, or cad cell
connections are shorted. Go to step 3.
Burner Starts
2. Trouble is in thermostat circuit. Check
thermostat and wiring connections.
Indicator Light Turns Off
permanently shield cad cell.
Ignition Is Not On
2. Ignition is not on. Replace R8991
control and ignition source.
Indicator Light Turns On
3. Indicator light is on until the control
locks out. Indicator light starts flashing
during lockout. Oil primary control is
defective; replace control.
Burner Locks Out
4. Check cad cell; go to step 5.
Indicator Light is On
5. Remount control onto burner housing.
Go to step 3.
Indicator Light is On
6. Replace cad cell bracket assembly.
5
Corrective Action
1. Indicator light is off. Go to step 2.
Burner Does Not Start
2a. Disconnect line voltage power and open
line switch.
2b. Check all wiring connections.
2c. Tighten any loose connections and
recheck.
2d. If burner still does not start, replace
R8991.
Indicator Light Stays On
3a. Replace cad cell with new cad cell (part
no. 130367) and recheck.
3b. If indicator light still does not turn off, cut
yellow lead wires near cad cell bracket
and recheck. If indicator light still does
not turn off, control is defective. Replace
R8991. If indicator light turns off, replace
cad cell bracket assembly.
Ignition Is On
2. Ignition is on. Go to step 3.
Indicator Light Stays Off
3. Indicator light does not turn on. Check
cad cell sighting for view of flame; go to
step 4.
Burner Keeps Running
4. Cad cell is okay.
Indicator Light is Off
5. Indicator light is off when good cad cell is
exposed to light. Check cad cell bracket
assembly; go to step 6.
Indicator Light is Off
6. R8991 is defective; replace R8991.
69-0669B—2