A.O. Smith Error Code LWR: Lower Element Fault
Warning: Your A.O. Smith water heater has detected a fault with the lower heating element and has shut down to prevent damage. You will not have hot water until this is resolved.
How to Fix A.O. Smith Code LWR
- Step 1: Check the water heater's circuit breaker in your electrical panel. Ensure it hasn't tripped. If it has, reset it. If it trips again immediately, do not reset it again and call a qualified technician.
- Step 2: If the breaker is fine, check the reset button on the water heater (usually a red button near the top). Press it firmly. If it clicks, that indicates the high limit switch had tripped. This might restore operation, but it's still important to have a technician investigate the underlying cause.
- Step 3: If the problem persists after checking the breaker and reset button, contact a qualified HVAC technician or electrician to diagnose and repair the issue.
How to Reset A.O. Smith Code LWR
- Turn off the unit using the power button on the front panel.
- Turn off the gas supply valve.
- Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
- Restore power at the breaker, then open the gas valve.
- Turn the unit back on. If the error returns, the underlying issue needs repair.
What does LWR mean?
The 'LWR' error code on your A.O. Smith water heater indicates a problem with the lower heating element circuit. The control board monitors the electrical current flowing through the heating elements. If it detects a short circuit, open circuit, or other electrical anomaly, it will display this error and shut down the element to prevent further damage or potential fire hazard. This usually means the element has failed, or there's a wiring issue. Because the water heater relies on both elements to properly heat water, a fault in one will prevent the unit from operating correctly. The lower element is especially important as it heats the larger volume of water at the bottom of the tank.
Affected Models
Replacement Parts
| Part | OEM Number | Est. Cost |
|---|---|---|
| Lower Heating Element | 9000766 | — |
| High Limit Switch | 100112098 | — |
| Thermistor | — | — |
Related Codes on Same Models
| Code | Description | Severity |
|---|---|---|
| E1 | Thermistor Failure | Warning |
| E2 | Dry Fire Protection | Warning |
| E3 | Sensor Fault | Warning |
| E4 | High Temperature Cutoff | Critical |
| E5 | Communication Error | Warning |
| E06 | Flammable Vapor Detection | Critical |
| ECO | Emergency Cutoff | Critical |
| LOC | Controls Locked | Warning |
| UPR | Upper Element Fault | Warning |