Short answer
The usual causes are a tripped breaker, a burned-out upper heating element, a failed thermostat, or a tripped high-limit cutoff. Check the breaker first. If it trips again or the breaker is fine, the fix involves 240-volt parts behind the access panels, which is work for a licensed plumber or electrician.
Key facts
- HomeGuide's 2025 range for replacing a water heater element is $100 to $350, and the same for a thermostat.[1]
- Under DOE's 2024 rule, electric storage water heaters in the most common sizes must reach entry-level heat pump efficiency for units made on or after May 6, 2029.[3]
- Rheem says a repair over 50% of the price of a new unit usually means replacement is the better buy.[2]
Start at the breaker panel
An electric water heater runs on a 240-volt circuit, usually through a double breaker (two handles tied together). Find the one labeled for the water heater.
- Tripped: The handle sits in the middle or the off position. Push it fully off, then back on, once. Wait an hour or so for the tank to heat.
- Trips again: Stop. A breaker that trips again points to a shorted element, damaged wiring or a failing breaker. See breaker keeps tripping and call a pro. Do not keep resetting it.
- Fine: The fault is in the heater itself. Move on.
Also check for a disconnect switch near the heater (some installs have one) and make sure it is on.
How an electric tank heats, in plain terms
Most residential electric tanks have two heating elements, one high and one low, each with its own thermostat. The upper thermostat runs the show: it heats the top of the tank first, then hands power to the lower element. A safety cutoff called the high-limit (often called the ECO) sits with the upper thermostat. If the water gets too hot, it cuts power to both elements until someone resets it.
That design explains the symptoms:
| Symptom | Likely cause | Who fixes it |
|---|---|---|
| No hot water at all | Tripped breaker, tripped high-limit, failed upper element or upper thermostat | Homeowner (breaker only); pro for the rest |
| Lukewarm water that runs out fast | Failed lower element or lower thermostat, heavy sediment, or a broken dip tube | Licensed plumber |
| Water too hot, then nothing | Thermostat stuck on, high-limit tripping | Licensed plumber (scald risk) |
| Breaker trips when the heater calls for heat | Shorted element or wiring fault | Licensed plumber or electrician |
What you can safely check
- The breaker and any disconnect switch, as above.
- The thermostat setting is not the issue. You cannot see the dial without opening a panel on most tanks, so if no one has worked on the heater, assume the setting did not change.
- Recent events. A power outage, a dry-fire after the tank was drained, or recent work on the panel are all useful facts to give the plumber.
- Water on the floor. A leak plus no heat can mean water reached the wiring. Turn the breaker off and call.
What not to do
Testing elements and thermostats means removing the access panels and putting a meter on terminals that carry 240 volts. A wrong move can cause a serious shock. Never turn the power on to an empty or partly drained tank; an element that runs without water around it burns out in seconds. Leave the panels, the high-limit reset and the wiring to a licensed plumber or electrician.
Repair costs
From HomeGuide's national figures, published August 2025[1]:
| Repair | Typical range |
|---|---|
| Tripped breaker or blown fuse | $10 to $20 |
| Heating element replacement | $100 to $350 |
| Thermostat replacement | $100 to $350 |
| Typical electric repair overall | $100 to $350 |
| Flush and clean tank | $75 to $250 |
Service call fees of $50 to $200 may apply[1]. Ranges are national and not quotes.
Repair or replace: the 2029 factor
Element and thermostat repairs are among the cheapest water heater fixes, so they usually make sense on a tank in good shape. Rheem's rule is to repair units under about 6 to 8 years old and to replace when the repair exceeds 50% of a new unit's price[2].
If you do replace, know where the rules are going. DOE's 2024 standard requires electric storage heaters in the most common sizes to reach the efficiency of an entry-level heat pump water heater for units made on or after May 6, 2029[3][4]. DOE estimates that a household replacing a standard electric tank with a heat pump unit meeting the new standard saves about $1,800 over the life of the heater[3]. Today you can still buy a standard electric tank. ENERGY STAR also certifies 120-volt plug-in heat pump models, which can suit homes without a 240-volt circuit in the right spot[5].
When to call a pro
- The breaker trips again after one reset.
- No hot water with the breaker on: element, thermostat or high-limit diagnosis.
- Water on or near the wiring or the access panels.
- Water hotter than normal, or any sign of scorching on the panels.
More questions
Why do I get a little hot water and then it goes cold?
On a standard two-element tank, that pattern often points to the lower element or lower thermostat, while no hot water at all points to the upper side or the high-limit. A pro confirms it with a meter.
Can I just press the red reset button?
The high-limit reset sits behind an access panel next to live 240-volt terminals. If it tripped, something made the water overheat, and a pro should find out what before it is reset.
Sources
- Hot water heater repair cost (Aug 7, 2025), HomeGuide. Accessed 2026-10-06.
- Water heater lifespan: when to repair vs. replace (Mar 25, 2026), Rheem Manufacturing. Accessed 2026-10-06.
- DOE finalizes efficiency standards for water heaters (Apr 30, 2024), U.S. Department of Energy. Accessed 2026-10-06.
- Consumer water heaters: rulemaking status, U.S. Department of Energy. Accessed 2026-10-06.
- ENERGY STAR water heater key product criteria, ENERGY STAR (U.S. EPA). Accessed 2026-10-06.
Water Heater Facts is an independent information service. We may be paid by contractors when we connect a homeowner with one; that never changes what we publish. Found an error? Tell us. We review safety and legal reports within 2 business days and all others within 7 days.