A.O. Smith 2000, 3400, 2600, 1700 instruction manual Ilk Off

CODE	DESCRIPTION	RECOMMENDED TROUBLESHOOTING OF		NOTE
			LOCKOUT CODES
67	ILK OFF	1.	Check wiring and correct any possible shorts.	H or L
		2.	Check Interlock (ILK) switches to assure proper
68	ILK ON			H or L
			function.
		3.	Verify voltage through the interlock string to the
			interlock input with a voltmeter.
		4.	If steps 1-3 are correct and the fault persists,
			replace the module.
69	Pilot test hold	1.	Verify Run/Test is changed to Run.	H
		2.	Reset Module.
		3.	If fault repeats, replace module.
70	Wait for leakage test completion	1.	Internal Fault. Reset Module.	H
		2.	If fault repeats, replace module.
71 - 77	RESERVED
78	Demand Lost in Run	1.	Check wiring and correct any possible errors.	H
		2.	If previous steps are correct and fault persists,
			replace the module.
79	Outlet high limit	1.	Check wiring and correct any possible errors.	H or L
		2.	Replace the Outlet high limit.
		3.	If previous steps are correct and fault persists,
			replace the module.
80	DHW high limit	1.	Check wiring and correct any possible errors.	H or L
		2.	Replace the DHW high limit.
		3.	If previous steps are correct and fault persists,
			replace the module.
81	Delta T limit	1.	Check Inlet and Outlet sensors and pump circuits	H or L
			for proper operation.
		2.	Recheck the Delta T Limit to confirm proper
			setting.
		3.	If previous steps are correct and fault persists,
			replace the module.
82	Stack limit	1.	Check wiring and correct any possible errors.	H or L
		2.	Replace the Stack high limit.
		3.	If previous steps are correct and fault persists,
			replace the module.
83	Delta T exchanger/outlet limit	Not Applicable.		H or L
84	Delta T inlet/exchanger limit	Not Applicable.		H or L
85	Inlet/outlet inversion limit	Not Applicable.		H or L
86	Exchanger/outlet inversion limit	Not Applicable.		H or L
87	Inlet/exchanger inversion limit	Not Applicable.		H or L
88	Outlet T-rise limit	Check for adequate flow.		H or L
89	Exchanger T-rise limit	Not Applicable.		H or L
90	Heat exchanger high limit	Not Applicable.		H or L
	Sensor Faults
91	Inlet sensor fault	1.	Check wiring and correct any possible errors.	H
		2.	Replace the Inlet sensor.
		3.	If previous steps are correct and fault persists,
			replace the module.
92	Outlet sensor fault	1.	Check wiring and correct any possible errors.	H
		2.	Replace the Outlet sensor.
		3.	If previous steps are correct and fault persists,
			replace the module.
93	DHW sensor fault	1.	Check wiring and correct any possible errors.	H
		2.	Replace the DHW sensor.
		3.	If previous steps are correct and fault persists,
			replace the module.

63