Crown Boiler Troubleshooting: Understanding Error Codes and Common Problems

C.Trouble shooting problems where a hard lockout code is displayed. When a hard lockout occurs, the boiler

will shut down and the display will flash the letter “E” followed by a two digit service code. Once the condition that caused the lockout is corrected, the boiler will need to be manually reset using the RESET button on the display.

Table 13.4: Hard Lockout Codes Displayed

CODE	CONDITION	POSSIBLE CAUSES
E 00	A flame signal was present when there should	• Defective gas valve - make sure inlet pressure is below maximum
	be no flame.	on rating plate before replacing valve.
		• No gas pressure
		• Gas pressure under minimum value shown on rating plate
		• Gas line not completely purged of air
		• Defective Electrode
		• Loose burner ground connection
E 02	Flame failure after 5 tries to restart	• Defective Ignition Cable
		• Loose or defective gas valve harness
		• Defective gas valve (check for 24 VDC at harness during trial for
		ignition before replacing valve)
		• Air-fuel mixture out of adjustment - consult factory
		• Blockage in vent system or heat exchanger (BWC 150 Only)
		• Blocked condensate trap (BWC150 Only)
E 03	Internal control failure	• Reset the control. If problem reoccurs, replace the MCBA.
E 04	Power failure occurred after lockout	• Some other error on this list occurred and power to the boiler was
		then interrupted. Reset control and see if hard lockout reoccurs.
E 05
E 06	Internal control failure	• Reset the control. If problem reoccurs, replace the MCBA.
E 07
E 11
		• If yellow light on LWCO is on, system is low on water
E 12	Low water cut-off circuit open	• If neither yellow nor green light is on, check LWCO harness and
		check for 24VAC across AT140 transformer
E 13
E 14
E 15	Internal control failure	• Reset the control. If problem reoccurs, replace the MCBA.
E 16
E 17
E 18	MCBA supply sensor detected temperatures in	• See possible causes for “b18” error. Also, check safety limit for
	excess of 200°F for an extended period of time	proper operation.
E 19	MCBA return sensor detected temperatures in	• See possible causes for “b19” error.
	excess of 200°F for an extended period of time
	Blower is not running when it should or fan	• Loose connection in 120 VAC fan wiring
E 28		• Loose or miswired fan speed harness
	speed signal not being detected by MCBA
		• Defective fan
E 29	Blower fan speed has not returned to zero rpm	• Miswired fan speed harness
		• Defective fan
E 31	Shorted supply temperature sensor	• Shorted or miswired supply sensor wiring
		• Defective supply sensor
E 32	Shorted return temperature sensor	• Shorted or miswired return sensor wiring
		• Defective return sensor
E 35	Flue gas temperature sensor short circuit	• Shorted or miswired flue temp sensor wiring
		• Defective flue temp sensor
E 36	Supply water temperature sensor circuit open	• Loose or miswired supply sensor wiring
		• Defective supply sensor
E 37	Return water temperature sensor circuit open	• Loose or miswired return sensor wiring
		• Defective return sensor
E 40	Flue gas temperature sensor circuit open	• Loose or miswired flue temp sensor wiring
		• Defective flue temp sensor
E 44	Internal control failure	• Reset the control. If problem reoccurs, replace the MCBA.
E 52	Flue gas temperature over 230°F	• Heat exchanger needs to be cleaned
		• Boiler over-fired
		• Air-fuel mixture out of adjustment - consult factory
E 60	Internal control failure	• Reset the control. If problem reoccurs, replace the MCBA.

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