No Hot Water
No hot water can come from several causes. On an electric heater, start with the external breaker status; internal elements, thermostats, wiring, or high-limit controls may require professional testing. On a gas heater, the visible pilot or ignition status and any error indicator can provide clues, but flame-sensing, gas-control, venting, or supply issues can produce similar symptoms. The goal is to check safe external items first rather than assuming one failed part.
- —Tripped circuit breaker or blown heating element (electric)
- —Pilot light out or failed thermocouple (gas)
- —Bad thermostat not calling for heat
- —Tripped energy cut-off (ECO) in the gas control valve
Try This First
Safe, simple steps you can try yourself. If any step feels beyond your comfort level, skip it and continue below.
- 1
Check the breaker panel (electric)
If you have an electric water heater, look for a tripped breaker in your electrical panel. If tripped, flip it fully off, then back on.
- 2
Check the pilot light (gas)
Look through the sight glass on the gas control valve. If the pilot is out, follow the manufacturer's relighting instructions. If you smell gas, stop and leave the area.
If the problem is resolved
If hot water returns and stays hot, the issue was likely a one-time breaker trip or pilot outage. Monitor it — if it trips again within a few days, a component is likely failing.
If the problem persists
If the breaker keeps tripping, the pilot won't stay lit, or the reset button trips repeatedly, continue below — a professional diagnosis is needed.
Stop and Call a Plumber If…
- The breaker trips again immediately after resetting
- The pilot light won't stay lit after relighting
- You smell gas near the heater — leave the area and call from a safe distance
- You hear a boiling sound or see steam — this is a safety hazard
- ✓Testing the heating elements with a multimeter (electric)
- ✓Testing the thermostat and high-limit switch
- ✓Checking the thermocouple and gas control valve (gas)
- ✓Verifying the pilot assembly and gas supply
- ✓Checking for sediment buildup that can cause overheating
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Reviewed by Paul Hall, Owner & Licensed Plumber
The Classic Plumber · Knoxville, TN · License #4268. This guidance is general — an onsite inspection may be required for a confirmed diagnosis.
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