Electric Water Heater Not Working After a Power Outage
On this page (7 sections)
The Short Answer: A standard electric tank has no pilot to relight, so if it stays cold after an outage, power is not reaching the elements. The usual reasons are a tripped double-pole breaker, a high-limit (ECO) that opened when power flickered, or a thermostat or element damaged by a surge. Check the breaker once, confirm the tank has water, and leave anything behind the access covers to a technician.
Give it time before you assume a fault
An electric tank heats slowly. A 40- or 50-gallon tank that cooled off during a long outage can take an hour or more to make usable hot water again. If the jacket is warming and you hear nothing unusual, wait one full recovery before you start checking things.
If there is a display or status light on the heater, as on hybrid heat-pump models and some electronic-thermostat tanks, write down any code before you touch the breaker. A heat-pump water heater that beeps after an outage has its own article: beeping after a power outage.
What usually happened
| What you notice | Likely cause | How urgent |
|---|---|---|
| Breaker handle in the middle or off | Breaker tripped during the surge or restart | Reset once; if it trips again, leave it off |
| Breaker on, tank completely cold | High-limit (ECO) opened, or one leg of the circuit is dead | Technician visit |
| A little hot water, then cold | One element or thermostat failed, often the lower one | Repair, not urgent |
| Burning smell, buzzing breaker, or hot breaker handle | Damaged connection or breaker | Turn the breaker off and call an electrician |
| Water on the floor | A separate leak | Shut the cold-water inlet and treat it as a leak |
What you can check safely
- The breaker. A water heater is normally on a double-pole breaker (two handles tied together). If it is tripped, push it fully off, then back on once. If it trips again right away or within minutes, leave it off; that points to a shorted element or wiring. Never hold a breaker on. More on that pattern in breaker tripped and won’t reset.
- Water in the tank. If your water also went out during the storm, for example because a well pump lost power, open a hot faucet and make sure water runs in a steady stream before the heater is powered again. An element switched on in an empty or partly empty tank can burn out in seconds. See water heater turned on without water.
- Any local disconnect or switch near the heater, which should be on.
- The temperature setting on the outside of any display. Some electronic controls go into vacation or standby mode after a power loss.
Why the red reset button is a technician’s job
Most electric tanks have a manual-reset high-limit (often called the ECO) on the upper thermostat, behind an access cover with live 240-volt terminals. Voltage dips and surges can open it, but so can a stuck thermostat or a shorted element. Pressing it without knowing why it tripped can lead to overheated water or a burned-up thermostat, so this site does not give it as an owner step. If you keep running into it, read why do I have to keep resetting my water heater.
What the technician will check
With the circuit locked off, a technician typically confirms that both legs of the 240-volt supply arrive at the heater, checks whether the high-limit has opened and why, and tests each element and thermostat. A surge can leave the tank partly working: the upper element heats but the lower one does not, which gives you a short burst of hot water and then lukewarm. They will also look for scorched wiring at the thermostat terminals, which is a common follow-on from a loose connection.
Repair or replace
An element, thermostat, or high-limit is a part replacement on a sound tank. Surge damage alone is not a reason to replace the heater. If the tank is old and also leaking from the shell, or the jacket is rusted through at the base, replacement makes more sense.
Frequently Asked Questions
Q: Will an electric water heater turn back on by itself after an outage? A: Usually yes. If the breaker stayed on and the high-limit did not open, it resumes heating when power returns. It just needs time to reheat a full tank of cold water.
Q: My gas water heater also stopped. Is that the same problem? A: No. Many gas tanks run without house power, while electronic-ignition and power-vent models need it. See gas water heater not working after a power outage.
Q: Can a power surge ruin the whole water heater? A: Surges usually damage replaceable electrical parts such as thermostats, elements, or electronic controls, not the tank itself. A technician can tell you which part failed.
Manuals and supporting references
These links distinguish general safety information from model-specific documentation. A manual directory helps you locate your unit’s instructions; it does not establish that every model uses the same parts, codes, or test values.
- A. O. Smith: standard electric no-hot-water diagnostic chart (opens in a new tab)Professional diagnostic context for standard electric storage heaters; not instructions to open or test your appliance.
Editorial standards and corrections · Prepare a useful service request