No Hot Water? Troubleshooting Gas and Electric Water Heaters

Before you open any panels, rule out the simple stuff. A surprising number of no-hot-water calls come down to a tripped breaker, an accidentally bumped thermostat setting, or a pilot that blew out. Figure out whether your unit is gas or electric first: a gas heater has a burner, a gas line, and a flue at the top, while an electric heater has a thick electrical cable and no gas line.

• Confirm the water heater is actually the problem, not a single fixture. If only one faucet is cold, the issue is that fixture, not the heater.
• Check the temperature setting, since someone may have turned the dial down. Aim for about 120 degrees Fahrenheit.
• Make sure you have not simply run out of a tank's worth of hot water after back-to-back showers; wait 30 to 60 minutes for recovery and retest.
• Look for water around the base. If the unit is also leaking, see our guide on a leaking water heater before going further.

On a gas unit, no hot water almost always means the burner is not firing. The usual suspects, in order, are the pilot light, the thermocouple, and the gas supply.

1. Check the pilot light. Remove the access cover near the bottom and look for a small flame. If it is out, follow the relight instructions printed on the tank label exactly.
2. If the pilot will not stay lit, suspect the thermocouple, the thin metal sensor whose tip sits in the pilot flame. When it fails, it tells the gas valve to shut off for safety, so the pilot dies seconds after you release the knob.
3. Confirm gas is flowing. Check that the gas shutoff valve on the supply line is open and that other gas appliances (stove, furnace) are working. If nothing gas-powered works, call your gas utility.
4. If you ever smell gas, stop. Leave the home and call your gas utility from outside before doing anything else. Do not flip switches or relight anything.
5. If the pilot lights and holds but you still get no hot water, the gas control valve or burner assembly may have failed, which is a job for a licensed plumber.

An electric water heater has no flame; it heats with two elements controlled by upper and lower thermostats. No hot water usually means lost power or a burned-out element.

1. Check the breaker. Water heaters run on a dedicated 240-volt double breaker. If it has tripped, switch it fully off and back on. If it trips again immediately, stop, because that points to a short or a failed element and needs a pro.
2. Press the reset button. There is a red high-temperature cutoff (ECO) reset behind the upper access panel. If it has tripped, press it once. Repeated tripping means an underlying fault.
3. Suspect a heating element. If you get lukewarm water or hot water that runs out fast, one of the two elements has likely burned out, a common failure in DFW because hard-water scale coats and overheats elements.
4. Consider the thermostats. A failed upper or lower thermostat can leave you with no hot water or the wrong temperature.
5. Testing elements and thermostats safely requires shutting off the 240-volt breaker and using a multimeter. If you are not comfortable working inside a live-capable electrical panel, this is the point to get matched with a licensed plumber.

The two problems point in different directions, so it helps to be precise about which one you have.

• No hot water at all usually means the heater is not firing or heating: a dead pilot, no power, a failed gas valve, or both electric elements out.
• Hot water that runs out too fast often means a broken lower heating element (electric) or a dip tube problem, so only the top of the tank heats.
• Lukewarm water that never gets hot can be a bad thermostat, a single failed element, or a heater that is simply undersized for the household.
• Rusty or smelly hot water points to a corroding tank or a spent anode rod rather than a heating fault, and can precede a leak.
• Across DFW, hard-water sediment is a repeat offender: it insulates elements and burners, so the unit works harder and fails sooner. Annual flushing helps.

If you rent, hot water is not just a comfort issue; it is a habitability issue. Under Texas Property Code Section 92.052, a landlord must make a diligent effort to repair a condition that materially affects the physical health or safety of an ordinary tenant, and hot water generally falls in that category. The same statute specifically requires landlords to provide equipment to supply hot water of at least 120 degrees Fahrenheit.

The tenant's obligations matter too: you generally must be current on rent and give the landlord written notice of the problem before the repair duty and remedies kick in. Keep a dated copy of your notice.

This is general information, not legal advice. If your landlord will not act, the Texas Attorney General and local tenant resources outline the notice-and-remedy steps in more detail. If you own your home, none of this applies; you just need the heater fixed.

Relighting a pilot or resetting a breaker is fair game for a homeowner. Replacing a thermocouple, gas valve, heating element, or thermostat, or diagnosing why a breaker keeps tripping, is where a licensed pro pays for itself, both for safety and to avoid guessing at parts.

Dallas Best Plumber is a free referral service. Tell us what your heater is doing through the quote form and we match you with a licensed, insured local plumber who serves your ZIP. The matched pro calls you back with a free, no-obligation quote to repair or, if the unit is old and failing, replace it. For planning only, water heater repairs in the DFW market typically run about $150 to $650, a typical market range, not a quote.

If your heater is also leaking or you smell gas, treat it as urgent, keep the gas or power off, and get matched right away.