A.O. Smith BTF-75 warranty Troubleshooting, Problem, Possible Malfunction, Service To Be Performed

WARNING: DO NOT BY-PASS ANY CONTROLS TO MAKE HEATER OPERATE. OPERATE ONLY AS WIRED FROM FACTORY.

TROUBLESHOOTING

For your safety, water heater service should be performed only by a qualified service technician.

Read the GENERAL SAFETY INFORMATION section first.

PROBLEM				POSSIBLE MALFUNCTION	SERVICE TO BE PERFORMED
	1)		Blower will not run
			A)	“ON/OFF” control switch turned off	Turn switch to the “ON” position.
			B)	Blower unplugged	Plug blower back into 115 vac. outlet.
			C)	No power at outlet	Repair service to outlet.
			D)	“ON/OFF” switch defective	Replace switch.
			E)	Control harness defective	Replace control harness.
			F)	Blower motor defective	Replace blower and motor.
		2)	Blower running, burner not on		Replace switch.
			A)	Fan not running fast enough to close	Check for low voltage, less than 102 vac., have service
				air switch contacts	checked and repaired.
					If voltage is above 102 vac., make sure there is not more than
					30 Equivalent feet of 3 inch pipe or 85 equivalent feet of 4 inch
					pipe installed or vent terminal blockage.
					If at least 102 vac., less than 30 equivalent feet of 3 inch pipe
					or 85 equivalent feet of 4 inch pipe and not terminal blockage,
					replace blower.
			B)	Air pressure switch defective	Replace switch.
			C)	Gas valve defective	Replace gas valve.
			D)	Control harness defective	Replace harness.
			E)	Igniter defective	Replace igniter.
			F)	Unit has completed three trials to light	Reset cycle by turning switch off and then back on. If unit
				and failed	does not light in three trials, call an authorized A.O. Smith
					service representative.
			G)	Discharge air limit tripped	Verify dilution air openings are free of obstructions.
NOT ENOUGH OR					Make sure there is no more than 30 equivalent feet of 3 inch pipe or
					85 equivalent feet of 4 inch pipe.
NO HOT WATER
					Check for low voltage, less than 102 vac., have service
					checked and repaired.
					Make sure vent terminal is not blocked.
	3)		Thermostat problems
			A)	Thermostat set too low	Turn temperature control higher.
			B)	Thermostat or ECO defective	Replace thermostat.
			C)	High limit control circuit open	Replace.
	4)		Others
			A)	Heater undersized	Reduce hot water use.
			B)	Low gas pressure	Contact an authorized A.O. Smith service representative.
			C)	Incoming water is unusually cold	Allow more time for heater to re-heat.
			D)	Leaking hot water pipes or fixtures	Have plumber check and repair leaks.
			A)	Blower does not run when heater fired	Take unit out of service immediately, call an authorized A.O.
					Smith service representative.
			B)	Not enough dilution air to mix with flue	Proper air circulation must be provided for combustion and
VENT PIPE TOO HOT				gases in “Tee”	dilution of flue temp. Refer to “INSTALLATION” section.
(ABOVE 170° F)			C)	Air in room too hot for mixing with flue gases	Room air to be used for dilution with combustion products in
					flue should be less than 90°F.
			D)	Wrong burner orifice	Install correct orifice.
			A)	Dirt in burner ports	Turn off heater and gas, clean burner head.
			B)	Combustion air path restricted	Clear area around heater and check under heater, remove
YELLOW FLAME					any debris under heater and in openings in bottom cover.
			C)	Not enough room air for proper combustion	Refer to installation manual - Confined and Unconfined Space
					statements on page 4 and 5 for required openings.
CONDENSATION			A)	Water on the floor under heater	See “CONDENSATION.”
			B)	Water dripping from fan	Provide drip “TEE” to catch condensation, refer to pages 8 and 10.
		Improperly sealed, hot or cold supply connections,			Turn off heater & water, repair unit.
WATER LEAKS		relief valve, drain valve or thermostat threads
		Leakage from other appliances or water lines			Inspect other appliances near water heater.
		Condensation of flue products			Refer to “CONDENSATION.”
LEAKING T&P VALVE		Thermal expansion in closed water system			Install thermal expansion tank (DO NOT plug T&P valve).
		Improperly seated valve			Check relief valve for proper operation (DO NOT plug T&P valve).
HOTWATERODORSORCOLOR		High sulfate or mineral content in water supply or			Drain and flush heater thoroughly, chlorinate, refill and flush
		iron or sulfate reducing bacteria in water supply			again then chlorinate water supply.
(RefertoCATHODICPROTECTION)

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