Nordyne Forced Air Gas and Oil Furnace M1M - Manual (Page 30)

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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 oil gun control only.
Burner does not start with a call for heat.
1. Check the electrical supply to the 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 flame).
a. If indicator light is on, the cad cell is seeing
stray light or the cad cell or controller is
defective.
b. If indicator light is off, go to step 5.
c. If flashing, refer below (a. 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 R7184
control.
Burner starts, then locks out on safety with
indicator light flashing at ½ second on, ½
second off.
a. Reset primary control.
To reset the control from lockout, the button
needs only to be pressed and released. If it
is in restricted mode, the button should be
held in for 30 seconds (until the light flashes
twice, or until the light stops flashing on
earlier models).
Note: Restricted Mode: If the control
locks out three times in a row without a
complete heat cycle between attempts,
the lockout becomes restricted mode.
1. If indicator light stops flashing and
ignition remains off, primary control
could be defective. If line voltage is
present at the ignitor terminals, but
there is no ignition, the ignitor is probably
defective and needs to be replaced.
2. If indicator light stops flashing, burner
turns on, but control locks out again,
check cad cell if cad cell is Okay,
replace primary control.
3. If indicator light continues to flash at
1/2 second on, 1/2 second off, verify
that control is not in restricted mode. If
restricted mode, reset it. If not in re-
stricted mode, replace R7184.
4. If indicator light stays off while the flame
is on, check cad cell sighting for view
of flame.
5. If burner locks out, check cad cell
resistance. (See Table 10)
6. If burner keeps running, system is
Okay.
7. If indicator light is off, check cad cell
assembly after disconnecting line volt-
age power.
b. Burner will not start, and indicator light is
flashing at 2 second on, 2 second off.
Hold the reset button down for 1-2 second.
If indicator light continues to flash, wait for 60
- 70 seconds. If it still continues to flash,
replace the primary control.
c. To check cad cell resistance.
Press and release the button during the run
mode. The light will flash to indicate the cad
cell resistance. For proper burner operation,
it is important that the cad cell resistance
reaover 1600 Ohms. For cad cell resistance,
see Table 10.
Figure 35. Periodic Cleaning
Table 10. Cad Cell Resistance when
sensing flame
Led Flashes Cad Cell Resistance in Ohms
1 0 - 400
2 400 - 800
3 800 - 1,600
4 >1600