American Water Heater 395T1996NOX Water Heater User Manual


 
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Servicing should only be performed by a Qualied Service Technician
FAULT CONDITIONS
The water heater is equipped with an ignition control that incorporates a diagnostic system to assist in
troubleshooting the appliance. The indicator codes on the ignition module are as follows:
LED INDICATION FAULT MODE
2 Flashes Flame sensed without call for heat.
3 Flashes Ignition Lockout.
Steady On Internal Control Failure
The LED will flash on for 1/4 second, then off for 1/4 second during a fault condition. The pause between
fault codes is 3 seconds.
INTERNAL CONTROL FAILURE
If the ignition control detects an error in its software or hardware, all outputs are turned off and the LED
displays a steady ON condition. If an internal control failure is indicated, replace the ignition control.
TROUBLESHOOTING GUIDE FOR IGNITION CONTROL
SYMPTOMS CAUSES
1. Control does not start a. Miswired.
b. No 24V AC power supply at TH/W terminal.
c. Bad control, check LED for steady on or flashing
code (see above Table).
2. Thermostat on -no spark a. Miswired.
b. No 24V AC power supply at TH/W terminal.
c. Bad control, check LED for steady on or flashing
codes.
3. Valve on - no spark during TFI a. Shorted electrode -establish 1/8 inch gap.
b. Check high voltage cable.
c. Miswired.
4. Spark on - valve off a. Valve coil open.
b. Valve wire disconnected.
c. Bad control, check voltage at gas valve terminals
PV1 and V2.
5. Flame okay during TFI - no flame sense after TFI a. Poor ground at burner.
b. Poor flame, check flame current.
c. Check flame rod position.
FLAME SENSOR CURRENT CHECK
Flame current is the current that passes through the flame from the sensor to ground. The minimum
flame current necessary to keep the system from lockout is 0.7 micro amps. To measure flame current,
connect analog DC microammeter to the FC-, FC+ terminals on the Ignition Control. Meter should read 0.7
microamps or higher. If the meter reads below "0" on scale, meter leads are reversed; disconnect power
and reconnect meter leads for proper polarity.