A.O. Smith THR-160 Installation Instructions And Use & Care Manual page 59

Error
Error Type
Code
E383 Inlet Water Over-Temp.
E384 False Flame Detec on
E385 Gas Valve - SV1
E388 Bypass Valve
E392 Fan - False Start
E393 Fan - Signal Loss
E394 Fan - Target Speed
1. Verify the inlet water temperature is not above the water heater's set tempera-
ture.
2. Remove the thermistor (do not lose the o-ring) and check for any dirt or debris.
Clean with Emery cloth. If the thermistor is damaged, replace it.
3. Check the Thermistor sensor wire for a short or disconnec on. Correct any loose
connec ons and replace any damaged wire/connector. If the error s ll occurs.
Contact a qualifi ed service technician.
WARNING! Working on an energized circuit can result in severe injury or death from
electrical shock.
1. Look through the sight glass for a fl ame. If the fl ame is present, immediately
shut off the gas to the water heater. Contact a qualifi ed service technician before
a emp ng to use the water heater.
2. If no fl ame is present and the fl ame LED on the display is lit, Check the fl ame
sensor wire for a short or disconnec on. Correct any loose connec ons and
replace any damaged wire/connector. If the error s ll occurs, contact a qualifi ed
service technician.
1. The PCB detects an incorrect voltage from the gas valve solenoid valve 1 (SV1).
Correct any loose connec ons and replace any damaged wire/connector. If the
error s ll occurs, contact a qualifi ed service technician to replace the gas valve.
1. Correct any loose connec ons and replace any damaged wire/connector.
2. Follow the draining procedure on page 55 to properly drain the water heater.
Remove the bypass valve and inspect for any debris or damage. Replace if need-
ed.
1. Check the fan motor wiring. Correct any loose connec ons and replace any
damaged wire/connector. If the error s ll occurs, contact a qualifi ed service
technician.
1. Check the fan motor wiring. Correct any loose connec ons and replace any
damaged wire/connector. If the error s ll occurs, contact a qualifi ed service
technician.
1. Check the fan motor wiring. Correct any loose connec ons and replace any dam-
aged wire/connector.
2. With the water heater power disconnected, check the exhaust vent and air
intake piping for any blockages. Remove any blockages.
3. If the error s ll occurs, contact a qualifi ed service technician.
Residen al Gas Tankless Water Heater Use and Care Guide • 59
TROUBLESHOOTING
Procedure