Installation Guide

(ET)
DIAGNOSTIC
LED
INDICATES CORRECTIVE ACTION*
7 FLASHES
(Red)
Lower thermistor sensor failure. 1. Turn off electrical power at the breaker.
2. Disconnect and reconnect electrical connections at Electronic Thermostat
(ET).
3. Check for resistance values of either open or short circuit. If either of
these conditions are present, replace lower thermistor sensor.
4. Check for resistance values of either open or short circuit. If either of
these conditions are NOT present, replace ET.
5. Turn on electrical power at breaker.
8 FLASHES
(Red)
Energy Smart® Module (ESM)
failure.
1. Turn off electrical power.
2. Check wires at the interface module for damage.
3. If this 8 flashes condition continues, replace module (ESM).
4. See “Overriding The Interface Module (ESM)” by unplugging from the
Electronic Thermostat (ET) on page 18. NOTE: Electronic Thermostat
(ET) will continue to be operate, hot water will still be available.
5. Turn on electrical power at breaker.
9, 10, 11, or 12 FLASHES
(Red)
Electronic Thermostat (ET) error. 1. Turn off electrical power.
2. Check wiring at Electronic Thermostat (ET) for damage.
3. Turn on electrical power at breaker.
4. If this code flashes condition continues, replace the Electronic
Thermostat (ET).
Residen al Electric Water Heater Use and Care Guide • 23
TROUBLESHOOTING
*These instructions are brief and intended as guidance for a qualifi ed person. If you lack the necessary
skills to perform these procedures call 1-877-817-6750 for assistance.