Field Controls MPL-B Furnace User Manual


 
30318 R4 9/9/2005
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Condition: Burner starts then locks out on safety with indicator light flashing at 1/2 second on, 1/2 second off. (Cont.)
Procedure Status Corrective Action
Ignition is off
Spark igniter could be defective. Check for line voltage at igniter
terminals. If line voltage is present, replace R7484.
Ignition is on. Go to Step 9.
8. Listen for spark after burner
turns on (after 2 second delay).
Ignition is on but no oil is being
sprayed into the combustion
chamber.
Wait for “Valve ON” delay to complete. Check oil supply, and oil line
valve. Check for filter blockage or seized oil pump.
Indicator light is on until the
control locks out and starts
flashing during lockout.
Replace R7184
9. Check indicator light after flame
is established, but before oil
primary control locks out.
Indicator light stays off. Go to step 10.
Burner locks out.
Go to step 11.
10. Check cad cell sighting for view
of flame.
a. Disconnect line voltage power
and open line switch.
b. Unplug cad cell and clean cad
cell face with soft clothe.
Check sighting for clear view
of flame. Replace cad cell in
socket.
c. Reconnect line voltage power
and close line switch.
d. Start burner.
Burner keeps running. System is OK.
Indicator light is on.
Remount control onto burner housing. Go to step 6.
11. Check cad cell.
a. Disconnect line voltage power
and open line switch.
b. Remove existing cad cell and
replace with new cad cell.
c. Disconnect all wires from
thermostat terminals to
ensure that there is no call for
heat.
d. Reconnect line voltage power
and close line switch.
e. Expose new cad cell to bright
light such as a flashlight.
Indicator light is off. Go to step 12.
Indicator light is on.
Replace cad cell bracket assembly.
12. Check cad cell bracket
assembly.
a. Disconnect line voltage power
and open line switch.
b. Remove cad cell wires from
quick connect connectors on
the R7184 and leave control
lead wires open.
c. Apply power to device.
d. Place jumper across cad cell
terminals after burner motor
turns on.
Indicator light is off. Replace R7184.
NOTE: Restricted Mode - (Limited Reset): In order to limit the accumulation of unburned oil in the combustion chamber, the control can be reset
only 3 times, after which, the control locks out. The reset count returns to zero each time a call for heat is successfully completed.
To reset from R
ESTRICTED MODE: press and hold the reset button for 30 seconds. When the LED flashes twice, the device has reset.
NOTE: Disable function: Pressing and holding the reset button will disable all functions until the button is released. The burner will restart at the
beginning of the normal heat cycle on
SAFETY CHECK.