Water heater lifespan in Las Vegas, and how to stretch it
Valley water is very hard, and summers are long and hot. Here is what the official and manufacturer figures say about water heater life, and the upkeep that matters.
Lifespan figures from the Department of Energy and the makers
The U.S. Department of Energy’s Energy Saver guide (2022) says: “Most storage water heaters last 10-15 years, while tankless water heaters can last more than 20 years.” Its Building America fact sheet on tankless units explains why: they store no water, so they are “less subject to corrosion than tank-type heaters”. We found no figure specific to Las Vegas, and we won’t guess one.
Valley water, sediment and the hot garage
The Las Vegas Valley Water District’s 2026 annual report (based on 2025 data) puts the valley’s hardness at 280 parts per million, or 16 grains per gallon. Inside a water heater, those minerals settle as sediment.
A. O. Smith’s electric water heater guide (2017) says the amount of lime deposits or sediment depends on the hardness of your water, and that “draining sediment extends the life of the tank, heating elements, and drain valves.” In very hard water it says to take out and check the heating elements every time you drain the tank. The Southern Nevada Water Authority lists “longer life of appliances” among the advantages of softened water.
If your heater sits in a garage, it sees the valley’s summer: the National Weather Service in Las Vegas gives a normal July high of 104.5°F (1991–2020). None of the sources we read puts a number on what a hot garage does to lifespan. A. O. Smith’s gas manual does warn that gasoline and other flammable products should never be stored near a gas water heater, which matters in a garage.
The rest of the house shows the same minerals; see what hard water does around a Las Vegas home.
How often to flush a water heater on 16-grain water
Flushing a water heater means draining water out through the drain valve to carry sediment with it. The sources differ on how often:
| Source | What it says |
|---|---|
| U.S. Department of Energy, Energy Saver guide (2022) | Drain a quart of water from the tank every 3 months to remove sediment, following the maker’s directions |
| ENERGY STAR heat pump water heater buying guide (2021) | Annual flushing and checking the anode rod help a long life |
| A. O. Smith gas manual (2014) | Drain and flush the tank every 6 months |
| A. O. Smith electric guide (2017) | Drain and flush after the first 6 months to see how much sediment builds up, then at least once a year depending on hardness |
At valley hardness, start with the shorter end of your own manual’s range and adjust to what comes out.
Flushing an electric tank yourself: A. O. Smith’s steps
These are the main steps in A. O. Smith’s electric guide. Gas models have their own steps for the gas control; follow your manual.
- Turn the heater’s circuit breaker off.
- Run a hot water tap until the water is cool, to avoid scalding.
- Connect a garden hose to the drain valve and run it to a drain, outside, or into buckets.
- Turn off the cold water supply valve and open the drain valve.
- Open a hot water tap to help the tank drain faster.
- If sediment came out, open the cold supply and let water run through until no more sediment drains, then close the drain valve.
- Refill with a hot tap open until water runs full. Do not turn the power back on until the tank is completely full.
If sediment has set so hard the tank won’t drain, A. O. Smith says to call a qualified person.
Anode rods and softened valley water
The anode rod is a metal rod inside the tank that wears away so the tank lining doesn’t. A. O. Smith calls it “a consumable item”. Its gas manual says that once the anode is depleted, “the tank will start to corrode, eventually developing a leak.”
Softening speeds this up. The gas manual says “artificially softened water is exceedingly corrosive” and that the anode should be inspected after a maximum of three years, then every year. The electric guide says that with a softener, “your anode rod will deplete faster than normal.” The gas manual also says never to remove the rod for good, as that voids any warranties. If you soften valley water, put an anode check on the calendar.
Signs your Las Vegas water heater is wearing out
- Rumbling while heating. A. O. Smith says sediment in the bottom of the tank causes “rumbling” or “percolating” sounds. Flush it.
- A rotten egg smell from hot water. A. O. Smith and the water district both link this to the anode.
- Water around the base. Once the anode is used up, the tank corrodes and eventually leaks.
- An error code from an electric heater. A. O. Smith says a diagnostic code should show if an element has failed, and that replacing lime-encrusted elements is usually easier and cheaper than cleaning them.
Repair or replace a water heater in a Las Vegas home?
No source we used gives a simple rule. The Department of Energy’s guide notes that a new efficient heater may cost more up front than repairing an old one, while its energy savings carry on for the life of the unit. Things to weigh: the heater’s age against the 10 to 15 year range, whether the tank itself leaks, and what the repair costs. If your softener is also ageing, see when a Las Vegas softener is worth repairing. If you’re replacing a softener at the same time, you can work out your size first.
Tankless owners: scale in the heat exchanger is the main risk. See tankless water heaters on hard Las Vegas water.
Sources for this page
- U.S. Department of Energy · Energy Saver home energy guide · 2022 · lifespans, draining a quart every 3 months, repair versus a new unit.
- U.S. Department of Energy · Building America fact sheet on tankless water heaters · 2009 · why tankless units corrode less.
- ENERGY STAR · heat pump water heater buying guide · 2021 · annual flushing and anode checks.
- A. O. Smith · installation and operating manual for residential gas water heaters · 2014 · flushing every 6 months, anode and softened water, warning signs, garage storage.
- A. O. Smith · use and care guide for residential electric water heaters · 2017 · draining steps, elements in very hard water, anode wear with a softener.
- Las Vegas Valley Water District · annual water quality report · 2026 (2025 data) · valley hardness; questions-and-answers page · undated · rotten egg odor and the anode.
- Southern Nevada Water Authority · home treatment systems page · undated · “longer life of appliances”.
- World Health Organization · background document on hardness in drinking water · 2011 · softened water and water heater life.
- National Weather Service, Las Vegas · temperature overview · 2026 (1991–2020 normals) · July normal high.
Questions we get asked
- What are the first signs of a water heater going bad?
- A. O. Smith's manuals list rumbling or percolating sounds from sediment, a rotten egg smell linked to the anode rod, and in the end a leak once the anode is used up and the tank corrodes.
- How long does the average water heater last in Las Vegas?
- We found no figure specific to Las Vegas. The Department of Energy gives 10 to 15 years for most storage tanks and more than 20 years for tankless heaters.
- Does hard water shorten water heater life?
- Hard water leaves sediment in tanks and lime on electric elements, and A. O. Smith says draining sediment extends the life of the tank, elements and drain valve. The World Health Organization says softened water probably gives a longer life for hot water heaters.
- Why do I only get 10 minutes of hot water?
- None of the sources we used ties one cause to this. In an electric heater, A. O. Smith's guide says a diagnostic code should show if an element has failed. Have a qualified person check the elements, thermostat and tank size against your household's use.
- How often should I flush my water heater in Las Vegas?
- Follow your own manual. A. O. Smith's gas manual says every six months; its electric guide says after the first six months, then at least once a year depending on hardness. ENERGY STAR mentions annual flushing.