Water Heater Maintenance: What Homeowners Should Do Each Year

Your water heater works every day and rarely gets any attention until it stops working. A little annual maintenance goes a long way toward extending the unit's life, keeping energy costs reasonable, and avoiding surprise cold showers. Most of these tasks take under an hour and do not require a plumber.

Why Annual Maintenance Matters

Water heaters in California typically deal with moderately hard water, especially in inland areas like Riverside, Sacramento, and parts of the San Diego region. Minerals in the water - primarily calcium and magnesium - gradually settle inside the tank and form sediment at the bottom. That sediment acts as insulation between the burner and the water, forcing the unit to work harder and raising your energy bill. Left too long, it can also damage the tank lining.

Most manufacturers recommend annual or semiannual maintenance. Skipping it for years can shorten a water heater's lifespan, which typically runs around 8 to 12 years for a conventional tank unit.

Step 1: Flush the Tank

Flushing removes sediment buildup and is the most impactful maintenance task you can do.

1. Turn the thermostat to the "Pilot" or "Vacation" setting (for gas) or turn off the circuit breaker (for electric).
2. Connect a garden hose to the drain valve near the bottom of the tank.
3. Run the other end to a floor drain, bucket, or outside - the water will be hot and may contain sediment.
4. Shut off the cold water inlet.
5. Open a hot water faucet somewhere in the house to allow air in and prevent a vacuum.
6. Open the drain valve and let the tank drain fully. The water may run rusty or contain visible particles at first - that is normal.
7. Briefly turn the cold water back on to flush any remaining sediment, then close the drain valve.
8. Refill the tank, restore power or gas, and wait for it to heat before using.

If sediment is heavy, you may hear popping or rumbling sounds as it shifts during draining. This is a sign the flush was overdue.

Step 2: Test the Pressure Relief Valve

The temperature and pressure relief valve (T&P valve) is a safety device that opens if pressure or temperature inside the tank rises too high. It should be tested annually.

Lift the small lever on the valve briefly - you should hear or see water release into the discharge pipe. Then let it snap back. If it does not release or it continues to leak afterward, the valve likely needs replacing. This is not a complicated repair, but it is important. A failed T&P valve is a safety concern.

If you are not comfortable doing this yourself, ask a plumber to include it during any service call.

Step 3: Check the Anode Rod

The anode rod is a metal rod - usually magnesium or aluminum - suspended inside the tank. It slowly corrodes so that the tank lining does not. When it is depleted, the tank itself starts to corrode.

Checking the rod requires shutting off the water, locating the hex head (often under a plastic cap on top of the unit), and using a socket wrench to remove it. If it is less than about half an inch in diameter or is heavily corroded, replace it. New rods generally cost around $20 to $50 depending on type and size.

This is one task many homeowners choose to have a plumber handle, as access can be awkward and the rod is sometimes difficult to loosen if it has not been removed in years.

Step 4: Inspect the Area Around the Unit

While you are at it, take a few minutes to look over the unit and its surroundings:

• Check for any moisture, rust stains, or corrosion around the base, connections, or relief valve discharge pipe.
• Confirm the draft hood and vent pipe (on gas units) are still properly connected and not blocked.
• Make sure the area around the unit is clear - especially in garages, where items tend to accumulate near the water heater.

Step 5: Check the Thermostat Setting

The U.S. Department of Energy recommends a water heater thermostat setting of 120 degrees Fahrenheit for most homes. Higher settings waste energy and increase the risk of scalding. If your household includes young children or elderly adults, staying at 120 is a reasonable choice.

Many older units have a dial with "A," "B," "C" rather than exact temperatures. In that case, a plumber or technician can verify the actual output temperature with a thermometer.

When to Call a Professional

Annual maintenance is DIY-friendly for most homeowners. But call a plumber if:

• The T&P valve leaks continuously or will not seat properly after testing
• The anode rod is completely depleted and the tank shows rust
• You hear loud banging or rumbling during operation
• The unit is more than 10 years old and showing signs of rust or leaking

Bottom Line

Sources and editorial notes

Prices and permit requirements vary by location, property, equipment, and scope. Treat price ranges as planning estimates and confirm current requirements with the relevant authority and contractor.

• California Contractors State License Board - when a contractor license is required
• US Department of Energy - Energy Saver
• US Consumer Product Safety Commission - home safety

Related guides

• Water Heater Making Noise? What Each Sound Means
• When to Repair vs. Replace a Water Heater
• What to Do When Your Heater Stops Working

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