To reset your AO Smith water heater, locate the reset button on the thermostat, press it firmly, and ensure power is restored to the unit.
Resetting your AO Smith water heater can solve common issues like no hot water or error codes. This guide covers gas and electric models with detailed instructions to safely restore operation.
Locating the Reset Button on AO Smith Water Heaters
The reset button location varies by model type:
| Model Type | Reset Button Location | Appearance |
|---|---|---|
| Gas Models | Near gas control valve | Red or black button |
| Electric Models | Behind thermostat panel | Red button marked “Reset” |
Gas Water Heater Reset Process
- Turn off gas supply valve
- Remove access panel screws
- Locate red reset button near control valve
- Press and hold for 3-5 seconds
- Replace panel and restore gas
Electric Water Heater Reset Process
- Turn off power at breaker
- Remove upper thermostat panel
- Press red reset button firmly
- Replace panel securely
- Restore power at breaker
Common Reasons Your AO Smith Needs Resetting
Thermal Switch Tripping
The thermal safety switch trips when the unit overheats. This often indicates:
- Blocked air intake
- Dirty flame arrestor
- Faulty thermostat
For persistent trips, check our guide on water heater thermostat replacement.
High Temperature Cutoff Activation
Electric models may trip if:
- Sediment buildup occurs
- Heating elements fail
- Thermostat malfunctions
When to Call a Professional
Contact an expert if:
- Reset button won’t stay engaged
- Unit trips immediately after reset
- You smell gas (evacuate first)
For complex repairs, consider licensed water heater specialists.
Maintenance Tips to Prevent Resets
Annual Flushing
Remove sediment that causes overheating. The U.S. Department of Energy recommends annual flushing.
Air Intake Cleaning
For gas models, clean the air filter every 6 months to prevent switch tripping.
Temperature Settings
Keep thermostat at 120°F (49°C) to reduce overheating risk while preventing legionella growth.
Troubleshooting Persistent Reset Issues
If your unit requires frequent resets:
| Symptom | Likely Cause | Solution |
|---|---|---|
| Reset button clicks but won’t stay | Faulty high-limit switch | Replace switch |
| No hot water after reset | Failed heating element | Test and replace elements |
| Burnt smell during reset | Electrical short | Immediately disconnect power |
For older units, consider upgrading to a modern energy-efficient model if repairs become frequent.
