30
it will be affected by another heat source.
b. Check for clean fi lter and proper air fl ow.
c. Check burner for proper gas fi ring rate.
d. Be sure unit is not undersized for its thermal
load.
e. Check thermostat anticipator. The nominal
anticipator setting is 0.4.
Burner Flame Without Motor Running
a. Gas valve stuck open, check gas valve for
proper operation (replace if necessary) and
inspect heat exchanger.
b. Check for 115 volts to the combustion blower
motor; replace if necessary.
c. If no power to combustion blower then check
wiring and control module; replace if neces-
sary.
Circulation Air Blower Will Not Operate Even
Though The Burner Does Operate
a. Check thermostat “G” wiring.
b. Check wiring to motor.
c. Check for a defective motor.
TROUBLESHOOTING - OIL GUN
Honeywell R7184 or Beckett 7505 controls
only.
Burner does not start with a call for heat.
1. Check the electrical supply to furnace.
2. Be sure the furnace door switch is in the on
position.
3. Check for line voltage at the oil primary control.
The voltage should be 115 VAC.
4. Check indicator light with burner off, no call
for heat (no fl ame).
a. If indicator light/green light is on, the cad
cell is seeing stray light or the cad cell of
controller is defective.
b. If indicator light/green light is off, go to step
5.
c. If light is fl ashing (red or green light on
Beckett7505 control), refer to the next
section: 1. Reset primary control.
5. Jumper T to T terminals on primary control.
a. If burner starts, check thermostat or limit
wiring connections.
b. If burner does not start, turn off power.
Check all wiring connections.
c. If burner does not start, replace primary
control.
Burner starts and then locks out on safety
with Honeywell R7184 indicator light fl ashing
½ second on, ½ second off. For Beckett 7505
control, the red light will fl ash.
1. Reset primary control: To reset the control
from (soft) lockout, the button needs only to
be pressed and released. For R7184 control,
if it is in restricted mode, the button should be
held in for 30 seconds (until the light fl ashes
twice). For 7505 control, if it is in restricted
mode, the button should be held in for 15
seconds until the red light turns off and the
yellow light turns on.
NOTE: Restricted Lockout: If the control locks
out three times in a row without a complete heat
cycle between attempts, the lockout becomes a
restricted (hard) lockout.
a. If the lights mentioned above stop fl ashing
and the ignition remains off, the primary
control could be defective. If line voltage is
present at the igniter terminals, her there
is no ignition, the igniter is likely defective
and needs to be replaced.
b. If the light stops fl ashing, burner turns
on, but the control locks out again, check
the cad cell. If the cad cell is operational,
replace the primary control.
c. If the light continues to fl ash at the interval
listed above, verify that the control is not
in restricted mode. If in restricted mode,
reset it. If not in restricted mode, replace
the control.
Figure 35. Periodic Cleaning
Table 10. Cad Cell Resistance when
sensing fl ame
LED Flashes
Ohms
Cad Cell
Resistance
1
0-400
2
400-800
3
800-1600
4
>1600