How to Reset a Water Heater — Gas, Electric, Tankless, Heat Pump

"Reset the water heater" is the first instruction support gives for almost any non-leak problem. The reset procedure depends on what type of heater you have. This page walks through all four.

Electric tank — ECO reset

Electric tanks have an Energy Cut Off (ECO) — a safety thermostat that trips if the tank shell exceeds about 180°F. When it trips, the unit goes dead. The ECO is built into the upper thermostat and has a red reset button.

Reset procedure

1. Shut off the breaker at the panel
2. Remove the upper access panel on the front of the tank
3. Pull back the insulation and the plastic safety cover (be careful — bare 240V terminals are exposed once power is on)
4. Locate the upper thermostat — it has a red button in the center
5. Press the red button firmly. You should feel a click
6. Replace the safety cover, insulation, and access panel
7. Restore the breaker
8. Wait 60-90 minutes for water to heat

If the ECO re-trips

This means the underlying problem is still present — the unit overheated for a reason. Investigate before resetting again:

• Thermostat stuck closed — element won't shut off, water overheats. Replace the thermostat
• Element shorted internally — running constantly. Replace the element
• ECO itself failed — rare. Replace the upper thermostat (which contains the ECO)

Don't keep resetting a tripping ECO — it's a safety device telling you something is wrong.

Gas tank — pilot relight

Gas tanks don't have an ECO in the electric sense — they have a thermocouple safety. If the pilot goes out, the thermocouple cools, the gas valve closes, unit goes dead. Relighting the pilot is the reset.

Relight procedure (standing pilot units)

1. Turn the gas control knob to "Off." Wait 5 minutes for any residual gas to clear
2. Turn the knob to "Pilot"
3. Press and hold the knob (or the pilot button next to it) down
4. While holding, click the igniter button repeatedly until the pilot lights (visible through the sight glass)
5. Continue holding the knob down for 60 seconds after the pilot lights — this allows the thermocouple to heat and signal "pilot lit" to the gas valve
6. Release the knob. The pilot should stay lit
7. Turn the knob to "On"
8. Set the temperature dial to 120°F

If the pilot won't stay lit

• Bradford White Defender / ICON units: the #1 cause is a dirty intake air filter at the base. Clean it before replacing the thermocouple. See BW intake filter cleaning
• Thermocouple failed — most common cause on other brands. $15-25 part, 45 min DIY. See thermocouple
• Gas valve solenoid failed — pilot lights but main burner won't fire. Dealer-only replacement
• Drafty install — air movement blowing out the pilot. Inspect the burner area for drafts

Electronic ignition units

Modern gas tanks with electronic ignition don't have a standing pilot. To reset:

1. Turn the gas control to "Off." Wait 30 seconds
2. Turn back to "On"
3. Open a hot tap to trigger a heating call
4. The unit should ignite the burner automatically

Tankless — error code reset

Tankless units display numeric error codes. The reset clears the displayed code and attempts to restart.

Level 1 — controller reset

1. Press the On/Off button on the controller for 3 seconds (or the dedicated reset button on some models)
2. Wait for the display to cycle
3. Unit attempts to restart

Level 2 — power cycle

1. Turn off the unit at the controller
2. Unplug the unit or flip its breaker
3. Wait 30 seconds
4. Restore power
5. Turn the unit back on

If the error code returns within 60 seconds of reset, the underlying fault is real. Don't keep cycling — look up the specific code:

• Rinnai error codes
• Navien error codes
• Rheem error codes

Heat pump / hybrid

Heat pumps have multiple reset paths depending on the failure:

Operating mode reset

1. Press the mode button on the front panel
2. Cycle through modes (Heat Pump, Hybrid, Electric, Vacation)
3. Select Hybrid (default)

ECO reset (resistance backup element)

Heat pumps include a resistance element with an ECO, same as standard electric. Reset procedure identical to electric tank above.

Compressor lockout

If the heat pump compressor refuses to start, it may be in a lockout. Power-cycle the unit (breaker off 30 seconds, back on). If the lockout persists, the issue is mechanical — call service.

When reset doesn't work

If you reset three times in a row and the same problem returns each time, the underlying fault is active. Stop resetting and diagnose:

• Electric tank, ECO keeps tripping — failed thermostat or element. See thermostat
• Gas tank, pilot won't stay lit — see thermocouple and pilot light
• Tankless error code re-throws — look up the specific code's diagnostic walkthrough
• Heat pump compressor lockout — refrigerant or compressor issue; call service

When to call a plumber

• Resetting hasn't fixed the issue after one or two attempts
• The reset button itself is damaged
• You smell gas during a reset attempt
• You're inside the warranty period — DIY work voids warranty for affected systems

Related guides

• Troubleshooting (brand-specific links inside)
• No hot water
• All parts
• Repair vs replace

Bottom line

Electric: red ECO button behind the upper access panel. Gas: pilot relight via the gas valve control. Tankless: On/Off button on the controller, then power cycle if needed. Heat pump: mode reset, then ECO if needed. If the reset doesn't hold, stop — find the underlying cause.