120 VAC Is Available At AMP Plug - Ignitor Does Not Heat Up
1.Disconnect power to the furnace.
2.Disconnect AMP plug to the ignitor, and check ignitor resistance with an ohm meter. Set on RX1 scale.
•Normal reading should be 40 - 75 ohms.
•If above or below this rating at room tem- perature change ignitor.
3.Check for continuity from ignitor receptacle to burner.
Main Flame Ignites - Burner Locks Out
•Ignition control is not properly grounded.
•Defective ignition control.
•Improper polarity of 120 volt power supply.
•Ignitor has hairline crack.
•Improper gas pressure or burner air adjustment is not allowing fl ame to contact ignitor tip for fl ame rectifi cation.
•Misaligned ignitor does not allow fl ame to contact ignitor tip for fl ame rectifi cation.
Burner Short Cycling - Thermostat Calls for Heat, Limit Switches Closed
•Check for polarity.
•Check ground.
•Check fl ue.
•Check combustion air.
•Check gas pressure.
•Check orifi ce.
•Check the position of ignitor, a normal reading should be
24 Volts Supplied To Gas Valve During Ignition - No Main Gas Flow
•Gas valve may be defective. Replace if necessary.
•Gas piping may be plugged. Check for adequate gas supply to gas valve at union.
Burner Operates - Insuffi cient Heat
•Check thermostat for proper setting and location. Thermostat should not be located where it will be affected by another heat source.
•Check for clean fi lter and proper air fl ow.
•Check burner for proper gas fi ring rate.
•Be sure unit is not undersized for its thermal load.
•Check thermostat anticipator. The nominal setting is 0.4.
Burner Flame Without Motor Running
•Gas valve stuck open, check gas valve for proper operation (replace if necessary) and inspect heat exchanger.
•Check for 115 volts to the combustion blower motor; replace if necessary.
•If no power to combustion blower then check wiring and control module;replace if necessary.
Circulation Air Blower Will Not Operate Even Though The Burner Does Operate
•Check thermostat G connection.
•Check wiring to motor.
•Check for a defective motor.
Oil Gun - Honeywell R7184 or Beckett 7505 Controls Only - M5S Series.
Burner does not start with a call for heat.
•Check the electrical supply to furnace.
•Verify the furnace door switch is in the ON position.
•Check for line voltage (115 VAC) at the oil primary control.
•Check indicator LED with burner off, no call for heat (no fl ame). See Table 9 (page 29).
-If green LED indicator is on, the cad cell is seeing stray light or the cad cell of controller is defective.
-If green LED indicator is off, go immediately to step 5.
-If LED indicator is fl ashing (red or green on Beckett 7505 control), refer to the next step 1 below - Reset primary control.
•Jumper T to T terminals on primary control.
-If burner starts, check thermostat or limit wiring connections.
-If burner does not start, turn off power.Check all wiring connections.
-If burner does not start, replace primary control.
Burner starts and then locks out on safety with Honeywell R7184 LED indicator fl ashing
½second on, ½ second off. For Beckett 7505 control, the red LED will fl ash.
1.Reset primary control: To reset the control from (soft) lockout, the button needs only to be pressed and released. If the R7184 control is in restricted mode, press and hold the button for 45 seconds - until the LED fl ashes once. If the 7505 control is in restricted mode, press and hold the button in for 15 seconds until the red turns off and the yellow LED 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.
2.If the LED indicator stops fl ashing and the ignition remains off, the primary control could be defective. If line voltage is present at the igniter terminals, and there is no ignition, the igniter is likely defective and needs to be replaced.
3.If the stops fl ashing, burner turns on, but the control locks out again, check the cad cell. If
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