No Hot Water? What to Check

By Austin Emergency Plumbing Pros · Updated September 2026

Start With What You Have

The first question is what kind of heater is in the house, because the checks are completely different. An electric tank has no flame and runs from a dedicated breaker. A gas tank has a burner, a pilot or igniter and a flue. A tankless unit heats on demand, usually has a display, and lives on a wall rather than standing on the floor.

The second question is whether the problem is no hot water at all or not enough of it. A complete loss points at power, gas or a failed control. Hot water that runs out early points at capacity, sediment or one of two elements having failed. That distinction saves the plumber a lot of time.

Electric Units: Breaker First

Check the breaker panel. A water heater breaker that has tripped is common and it is safe to look. If it has tripped, you can reset it once. If it trips again straight away, stop and call, because something is drawing a fault and repeatedly resetting it is not a fix.

Beyond the breaker, an electric heater has two elements and two thermostats behind removable panels. Those panels cover live terminals. Unless you know how to isolate and test them, leave them closed. A single dead element is the classic reason for lukewarm water that runs out fast, and it is a straightforward repair for someone with a meter in their hand.

Gas Units: The Pilot and the Vent

On a gas heater, look at the status light or the pilot window without dismantling anything. Many units have a small indicator that flashes a fault code, and writing that pattern down is genuinely useful when you call.

If the pilot is out, modern units have a documented relighting procedure on the label. Follow the manufacturer instructions exactly or leave it alone. If you smell gas at any point, do not touch switches or the control, leave the building and call the gas utility from outside. A pilot that lights and then dies within a minute usually means a failed thermocouple, which is a repair, not a replacement.

Tankless Units and Error Codes

Tankless heaters tell you more than tanks do. Note the code on the display, because it often narrows the cause down before anyone arrives. Check that the unit has power, that the gas is on and that the inlet filter is not obstructed if it is accessible from outside the cabinet.

Do not open the casing. The heat exchanger side of a tankless unit is not something to poke at, and scale build-up inside it is the most common reason for a unit that fires, runs and then drops out partway through a shower.

Hard Water Is Usually in the Story

Austin water carries a lot of dissolved mineral out of the Edwards region, and it leaves scale wherever it is heated. In a tank that means a sediment layer sitting over the burner or around the lower element, which insulates it, makes the unit rumble as it heats and shortens how long the hot water lasts.

In a tankless unit the same mineral coats the heat exchanger and gradually reduces its output until the unit starts faulting. Descaling on a schedule is what prevents that. If a heater in this city has never been flushed or descaled, that alone often explains the complaint.

What Not to Touch

Do not drain a hot tank. Do not lift the temperature and pressure relief valve to see what happens. Do not adjust a gas control you are unsure of, and do not open electrical panels on the unit. If the heater is leaking and you can safely reach the breaker or the gas control, turn that off and close the cold inlet valve on top of the tank; if it is in an attic or awkward to reach, leave it and say so when you call.

Hot Water Calls Around Austin

Where the heater lives matters as much as what is wrong with it. Attic installations are common in Austin and the surrounding suburbs, and they need a working drain pan and drain line as much as they need heat, because a leak up there arrives in the ceiling below. Garage and closet units are easier to work on but often sit behind stored belongings.

Tell the plumber the location, the type and the age when you call. Coverage includes the surrounding towns, such as emergency plumbing in Cedar Park.

Arrange an Inspection

If the safe checks have not explained it, the next step is a diagnosis rather than a guess at a new unit. Independent plumbers handle water heater repair on gas, electric and tankless systems. If replacement does come up, work through repair versus replacement so you know what should decide it. Water pooling near the heater but no obvious leak on the unit is a job for leak detection, or you can simply describe the symptom and get a visit planned.