Summer Water Heater Maintenance: Flush, Inspect, and Save

Why summer is ideal for water heater maintenance

Most homeowners don't think about their water heater until it fails — usually on a cold morning when hot water matters most. Summer maintenance is smarter: you're not relying on hot water as heavily, plumbers have more availability, and you can catch problems before winter demand spikes. A well-maintained water heater lasts 12–15 years instead of the typical 8–10, and runs 10–20% more efficiently.

Annual flush: the single most important task

Sediment (calcium, sand, mineral deposits) settles at the bottom of your tank over time. This layer insulates the water from the burner, forcing the heater to work harder and driving up energy bills by 15–25%. In severe cases, sediment causes the bottom of the tank to overheat and crack. Flushing removes this buildup.

• Turn off the gas or electricity to the water heater
• Attach a garden hose to the drain valve at the base of the tank
• Run the hose to a floor drain, utility sink, or outside — the water will be hot
• Open the drain valve and the pressure relief valve (or a hot faucet upstairs) to break the vacuum
• Let the tank drain completely — this takes 15–30 minutes
• Briefly open the cold water supply to stir up remaining sediment, then drain again
• Close the drain valve, refill the tank, and restore power — don't turn on a gas burner or electric element with an empty tank

Check the anode rod

The anode rod is a sacrificial metal rod (usually magnesium or aluminum) that corrodes instead of your tank's steel lining. Once it's depleted, the tank itself starts to rust. Most anode rods need replacement every 3–5 years, but hard water can accelerate this. To check: unscrew the rod from the top of the tank using a 1-1/16" socket wrench. If it's less than ½ inch thick or covered in calcium, replace it ($20–$50 for the rod, $150–$300 if a plumber does it).

Test the temperature and pressure (T&P) relief valve

The T&P valve is a critical safety device that releases water if tank pressure or temperature gets dangerously high. Lift the lever briefly — water should flow freely through the discharge pipe. If the valve doesn't release water, drips continuously, or is crusted with mineral deposits, have it replaced by a plumber ($20 for the part, $100–$200 installed). A stuck T&P valve can lead to a tank explosion — this is not a component to ignore.

Inspect the tank and connections

• Look for rust, water stains, or moisture around the base of the tank — early signs of a tank leak
• Check the hot and cold water connections for drips or corrosion
• Inspect the gas line (gas heaters) for any smell of gas or visible damage
• Verify the exhaust vent (gas heaters) is properly connected and not blocked
• Check the thermostat setting — the DOE recommends 120°F (49°C) for efficiency and scald prevention

When to call a plumber

Call a professional if you notice rusty water coming from hot taps, loud popping or rumbling sounds from the tank (severe sediment buildup), visible leaks at the base, or if the water heater is more than 10 years old and has never been serviced. A professional flush and inspection costs $100–$250 and typically includes checking all components, flushing the tank, and testing the T&P valve — a small investment that can prevent a $1,500–$3,000 emergency replacement.