How to Safely Restart a Rheem Water Heater

Check for Gas Smells and Water Leaks First

Before grabbing a screwdriver or pushing buttons, inspect the space around your tank. Water heaters store huge amounts of energy as scalding water, high-voltage electricity, or combustible gas. Rushing into a restart without checking your surroundings creates a serious safety hazard.

Start by taking a slow breath through your nose. Fuel suppliers add mercaptan to gas lines, giving escaping fuel a sharp smell like rotten eggs or boiled cabbage. If you smell even a faint trace of this odor near your Rheem water heater, stop immediately. Do not push buttons, flip light switches, or unplug nearby cords. Any tiny electrical spark can ignite gas trapped in a closet or basement. Step outside into fresh air right away and call your gas utility or fire department from your mobile phone.

Next, look at the floor around the base of the tank. If you see standing water, step back. Leaks from tank failure, loose pipe fittings, or a dripping relief valve create a shock hazard on electric models. If water surrounds an electric heater, do not touch the tank. Go straight to your main electrical panel and cut power from there before stepping onto the wet floor.

Review this safety checklist before touching the tank:

• Confirm there is no rotten egg or sulfur odor near the heater or floor.
• Check that the floor beneath your feet and around the tank is completely dry.
• Verify that no paint cans or flammable sprays sit within three feet of the heater.
• Check top pipes to confirm water is not dripping onto electrical panels.

Press the Red Reset Button on Electric Models

Electric Rheem water heaters do not use a pilot flame. They rely on two electric heating elements submerged inside the tank. When water gets dangerously hot, an automatic safety switch shuts down the whole unit to keep the tank from overheating.

Restarting an electric Rheem tank requires resetting this safety switch. You will find it behind the upper metal access panel on the side of the tank. Follow these steps to restart the unit safely:

1. Turn off power at the main breaker. Head to your electrical panel. Look for the circuit breaker (the main electrical switch in your home service panel) assigned to your water heater, usually a double-pole 30-amp switch. Flip it completely to "Off". Never open an access panel while the breaker is active.
2. Remove the upper access panel. Use a screwdriver to remove the two screws holding the upper cover plate to the tank. Set the screws aside where they will not roll away.
3. Fold back the insulation carefully. Behind the metal cover, you will see fiberglass insulation and a clear plastic cover. Gently fold the insulation outward. Do not yank on wires or pull the plastic shield loose. Never touch exposed screw terminals beneath the plastic, even with power off.
4. Locate the red reset button. Look through the plastic cover near the top of the thermostat. You will see a small, bright red button. This is the high-limit switch (a red safety button that cuts power if water overheats).
5. Press the red button firmly. Use your thumb to press the red button straight inward. If the safety switch tripped, you will hear and feel a distinct, crisp click. If you feel zero movement, the switch was not tripped, and your loss of hot water stems from another issue like a tripped breaker or a dead heating element.
6. Reinstall the insulation and cover. Fold the insulation back over the thermostat. Reattach the metal access panel and tighten both screws securely before restoring electricity. Operating an electric water heater without its metal covers installed creates a serious fire hazard.
7. Restore power at the breaker box. Flip the water heater breaker firmly to "On". Give the tank one to two hours to reheat before checking the hot water tap at your sink.

Relight the Gas Pilot Flame Using the Igniter

Gas Rheem water heaters use a small pilot flame to light the main burner whenever the tank needs heat. If a draft, a gas interruption, or a dirty sensor puts that flame out, the unit stops heating entirely.

Modern Rheem gas water heaters use a sealed burner system with a push-button sparker. Follow these steps to relight your pilot flame safely:

1. Expose the viewing window. Remove the outer metal door at the bottom front of the water heater. You will see a sealed plate with a small glass sight window. This window lets you view the combustion chamber without exposing room air to the burner.
2. Turn the gas knob to off. Turn the temperature dial on the front of the tank down to its lowest setting. Then, turn the main gas control knob clockwise to "Off".
3. Wait ten minutes for gas to clear. This step is mandatory. If the burner recently went out, unburned gas might linger inside the chamber. Waiting ten minutes allows the chimney draft to pull trapped fumes out through the exhaust vent. If you smell gas during this wait, stop and call a professional.
4. Turn the knob to pilot and hold it down. Rotate the gas control knob counterclockwise to "Pilot". Push the knob down firmly into the valve body and hold it down. This manually feeds gas directly to the pilot tube.
5. Click the igniter button repeatedly. While holding the gas knob down, press the piezo igniter (a push button that clicks to throw a lighting spark) once every few seconds. You will hear a sharp click with each press.
6. Check the sight glass for a blue flame. Look through the glass window while clicking. Look for a tiny blue flame to catch at the tip of the pilot tube.
7. Hold the knob down for one full minute after lighting. Keep holding the knob down for 30 to 60 seconds after the flame catches. This allows the flame to heat the thermocouple (a heat sensor that shuts off gas when the pilot goes dark). When heated, it signals the valve to keep gas flowing.
8. Release the knob and verify the flame. Slowly release the knob. If the blue flame stays lit, your pilot is working. If the flame vanishes, wait ten minutes to clear the gas and repeat the steps, holding the knob down slightly longer.
9. Turn the valve to the on position. Turn the gas knob to "On". Set the temperature dial to your desired warmth, ideally 120 degrees Fahrenheit (marked by a triangle or "Hot" on Rheem valves). The main burner will ignite with a steady whoosh. Replace the outer metal access door.

On Rheem models with an electronic status light, look at the small light-emitting diode (LED). Once the pilot catches, it will begin blinking. One steady flash every three seconds indicates normal operation.

Understand Why Your Water Heater Stopped Working

A water heater rarely shuts down without a clear mechanical reason. The safety switches inside your Rheem unit protect your home from burst pipes, fires, or gas leaks. Knowing why the shutdown occurred helps keep the issue from returning.

On an electric water heater, the red reset button trips when water reaches 170 to 180 degrees Fahrenheit. The most common culprit is a failed thermostat stuck in the "on" position, heating constantly past your set temperature. Another frequent cause is a burned-out heating element with a cracked casing that shorts out against the tank wall, heating uncontrollably until the safety switch cuts power.

On a gas Rheem water heater, a pilot flame usually goes out due to thermocouple problems or poor airflow. Over time, carbon deposits coat the heat sensor, preventing it from detecting the flame. When the sensor stays cool, it cuts the gas supply to prevent unburned fuel from pooling.

Airflow issues also cause sudden flame loss. Rheem tanks have an arrestor screen under the burner that pulls in fresh oxygen. If dust, pet hair, or lint clogs this screen, the flame starves and dies. Outdoor downdrafts through the exhaust chimney can also blow the pilot out. If your unit sits in a drafty space or a manufactured home, air pressure shifts can disrupt venting; learning how to choose a heater for a mobile home shows how balanced airflow protects heating equipment. In cold basements or garages, freezing drafts can also chill the burner intake, which is why maintaining steady room warmth with an auxiliary electric heater for a garage with a thermostat helps prevent flame flutter and heavy flue condensation.

Call a Professional When the Heater Trips Repeatedly

Resetting your water heater once after an unusual storm, power blip, or gas supply interruption is normal troubleshooting. But repeatedly pressing the reset button or relighting a pilot that dies every few hours is dangerous.

Forcing an electric heater to run by repeatedly clicking the reset button can boil the water inside your tank. Superheated water creates extreme pressure that can rupture plumbing or burst the tank. If the safety switch keeps popping, internal components have failed and need to be checked with a multimeter or replaced by a qualified technician.

Call a licensed plumber or electrician if you run into any of these warning signs:

• The red reset button pops back out immediately after pressing it.
• You notice a burnt plastic odor, blackened wire insulation, or melted terminal covers inside the access panel.
• The pilot light goes out the instant you release the gas knob, even after holding it down for two minutes.
• The status light on your gas control valve flashes a lockout code for overheating or a vapor sensor trip.
• You hear loud popping, knocking, or rumbling sounds from inside the tank, signaling heavy sediment buildup.
• Water drips from the tank casing, heating element gaskets, or the temperature and pressure relief valve.
• Water from your faucets is boiling hot and spitting steam, proving your thermostats have lost temperature control.