State Water Heater Error Codes
State Water Heaters are manufactured by A.O. Smith and use nearly identical control systems. State models include ProLine, ProLine XE, Select, Vertex, and Premier series. Error codes depend on the model type.
Gas Tank Models — LED Flash Codes
State gas water heaters with piezo ignition and thermocouple control use an LED status indicator on the gas valve:
| Flash Code | Meaning | Action |
|---|---|---|
| 1 flash (slow) | Normal — pilot lit | None |
| 2 flashes | Thermopile voltage low | Clean thermocouple, relight pilot |
| 3 flashes | Pressure switch (power vent) | Check vent, inducer |
| 4 flashes | Exceeded temperature limit | Lower setpoint, check safety |
| 5 flashes | Sensor fault / wrong reading | Replace temperature sensor |
| 6 flashes | Gas valve solenoid fault | Replace gas control valve |
| 7 flashes | Pilot failed to light | Relight pilot, check thermocouple |
| Rapid flashing | Control board fault | Replace gas control valve |
State gas valves are commonly made by Honeywell or White-Rodgers — same flash codes as Rheem and Bradford White.
Electric Models — Display Error Codes
State ProLine XE and Select electric water heaters with digital controls:
| Code | Meaning | Fix |
|---|---|---|
| E1 | Upper element or sensor fault | Test element (see below) |
| E2 | Lower element or sensor fault | Test lower element |
| E3 | Thermostat or sensor fault | Replace thermostat |
| E4 | Control board error | Replace board |
| E5 | High limit tripped | Reset, investigate |
| EE | EEPROM memory fault | Power cycle, then replace board |
Testing Electric Elements
Most State electric water heaters use two heating elements (upper and lower). To test:
- Turn off circuit breaker
- Remove access panel, push insulation aside
- Disconnect wires from element
- Set multimeter to ohms
- Measure across the two element terminals
- Normal: 8–25 ohms depending on wattage
- Shorted element: reads 0 ohms — replace immediately
- Open element: reads OL — replace
Common State element spec: 4500W / 240V = ~12.8 ohms
Resetting High Limit (E5)
The high-limit thermostat (ECO — Energy Cut Off) is behind the upper access panel, under the insulation. It’s a red-button reset device. After resolving the cause (thermostat failure, failed element creating runaway heat), press the red button firmly until you hear a click.
Heat Pump Models — State Hybrid
State ProLine XE Heat Pump (GPHE series) shares controls with A.O. Smith Voltex:
| Code | Meaning |
|---|---|
| E1 | Temperature sensor fault |
| E2 | Refrigerant system fault |
| E3 | Fan motor fault |
| E4 | Control board fault |
| E5 | Compressor fault |
In ELECTRIC mode, all E-codes disappear and the unit runs on resistance only. If your unit shows E2–E5 only in HEAT PUMP mode, the refrigerant circuit is at fault — requires a certified HVAC technician.
Power Vent Models — 3 Flashes Diagnosis
State power vent water heaters (SPDH, GPVD series) add a combustion blower to pull exhaust out. Code 3 flashes means the pressure switch on this blower didn’t close.
Check:
- Blower running? Listen at the exhaust pipe.
- Vent pipes clear? Check both ends outside.
- Pressure switch hose connected and intact?
- Test switch with gentle suction — should close (read continuity).
Anode Rod and Water Quality
State water heaters come with a magnesium anode rod. If your water smells like sulfur (rotten eggs), the anode is reacting with certain bacteria in the water. Replace with an aluminum/zinc anode rod — this eliminates the odor in most cases. Inspect anode every 3–5 years.
When to Replace vs. Repair
| Situation | Recommendation |
|---|---|
| Heater under 8 years, clear error code | Repair (replace component) |
| Heater 8–12 years, E4 (board fault) | Consider replacement — parts cost approaches heater value |
| Heater over 12 years, any fault | Replace entire unit |
| Heater leaking from tank body | Replace immediately — tanks do not repair |