A.O. Smith INTELLI-VENT, Troubleshooting Manual

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INTELLI-VENT TROUBLESHOOTING GUIDE
Technical Training Department Ashland City, Tennessee © 2005
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ERROR CODE 2 - REVERSED POLARITY
Power supply to Intelli-Vent™ control has reversed polarity.
Check / Repair:
• Insure the wall outlet is properly wired.
• Insure all internal 120 VAC wiring connections on the water heater are not
reversed. 120 VAC “hot” wire should connect to the on/off switch.
• Insure the wiring harness between the Intelli-Vent control and the wiring box has
no crossed wires with an ohm meter. (see 7)
• Double check all ground connections insure they are clean, tight, and intact.
ERROR CODE 3 - PRESSURE SWITCH CIRCUIT REMAINS CLOSED
†
Pressure switch circuit (see 7) remaining closed for more than 5 seconds after heating
cycle is activated. Blower does not start.
Check / Repair:
• Insure air pressure switch circuit wiring is correct and the air pressure switch is not
jumpered.
• Turn off power and unplug the water heater from wall outlet. Disconnect both
wires from the air pressure switch terminals. Check between the wiring terminals
of the air pressure switch with an ohm meter for continuity.
A If pressure switch contacts show continuity (closed circuit) replace the
pressure switch.
B If pressure switch contacts show open circuit and all wiring is correct - replace
Intelli-Vent control.
†.
To verify a closed air pressure switch circuit is preventing the heat sequence from advanc-
ing (IE the combustion blower is not being energized): Turn off power & unplug the water
heater from the wall outlet. Disconnect one wire from the air pressure switch (tape off end
of wire - insure this wire does not touch ground). Plug the water heater back in and turn
the power switch back on. If a call for heat is still present error code 3 should not return
and the Intelli-Vent control should energize the combustion blower.
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