PDF download Download Article
Follow this checklist to keep your water heater in prime condition
PDF download Download Article
This article was created in collaboration with an advertising partner. Learn more here .

You probably don’t think about your water heater much until it breaks, and you’re stuck with ice-cold showers in the middle of winter. Fortunately, some straightforward preventive maintenance can prevent this issue and keep your heater running more efficiently for longer. In this article, we’ll walk you through the important maintenance you should do each year to keep your water heater (conventional or tankless) in tip-top shape. Plus, we’ll review the signs that your water heater needs a repair—or when it’s time to replace it entirely.

Annual Water Heater Maintenance Checklist

  • Test the temperature and pressure relief (TPR) valve.
  • Flush the tank to remove sediment and mineral buildup.
  • Adjust the thermostat to raise or lower the water temperature to 120 degrees Fahrenheit.
  • Examine the anode rod in the tank and replace it if needed.
  • Look for and repair any leaks or drips in connections, or pipes. Tank leaks cannot be repaired.
  • Clean the air intake filter and vents.
  • Insulate the tank and pipes for better heating efficiency if needed.
  • Contact a professional at Roto-Rooter if your water heater needs repairs.
Section 1 of 6:

Hot Water Heater Maintenance Guide

PDF download Download Article
  1. The TPR valve is a safety feature that releases pressure from inside the water heater (gas or electric) to keep it from exploding if it becomes over-pressurized. It’s usually on the side of the tank—look for a lever connected to a long drain pipe that extends downward to direct water away from the tank. To test it: [1]
    • Turn off the power to electric heaters or switch gas heaters to pilot mode. Turn off the cold water supply.
    • Place a bucket or container under the drain pipe to catch water.
    • Lift and then release the lever, listening for flowing water or hissing air.
    • A functioning TPR valve will release a burst of hot water or air into the drain pipe. If you do not see or hear anything moving through the valve (or it continues to run after you’ve closed it), it needs to be replaced. [2]
    • If it’s broken: Call a professional to replace the valve if you're uncomfortable doing it yourself. Otherwise, drain the tank part way so the water level is below the valve, unscrew the current valve with a pipe wrench, and screw in a new valve (make sure the spout is facing downward). A new valve costs $15-30.
  2. Over time, sediment and minerals from your water can accumulate inside your water heater, causing it to run less efficiently. It’s a good idea to fully flush your heater once a year, and professional plumbers like those at Roto-Rooter recommend draining the tank about a quarter way several times a year to stay on top of buildup. [3] To flush your tank: [4]
    • With the water heater and cold water supply turned off, connect a hose to the drain valve on your heater (near the bottom) and run the other end into a ground drain or large bucket. (If your heater is below ground, like in a basement, you may need 2 hoses and a pump to channel the water outside if a floor drain or sump pit isn’t available. Otherwise, gravity will do the job.)
    • Open up a hot water faucet at the highest point in your home (like in a second-floor bathroom).
    • Open the drain valve on the water heater and let the water drain out completely.
    • Turn on the cold water supply at the top of the water heater tank for 2-3 minutes to rinse and stir up any remaining sediment in the tank. Repeat as necessary until the water drains clear.
    • Once clear, close the drain valve and open the water fill (cold) valve (at the top of the tank). Leave one faucet open in the house to purge the tank of air.
    • Afterward, turn the power back on to your heater.
    • If sediment is blocking the drain valve: Connect a nearby faucet to the drain hose with a washing machine hose. Turn on the faucet to blast the sediment backward through the valve and into the water heater tank to clear the clog. If this doesn’t work, call a professional.
  3. Some manufacturers set the water heater to 140°F (60°C), but this scalding temperature is often unnecessary for most households and can lead to faster corrosion and buildup in the pipes. To extend the life of your heater (and save some money on energy), adjust the temperature to 120°F (49°C). [5] To adjust:
    • Find the temperature dial, usually located on the side of the tank. (Note: Some models have their temperature dial behind an access panel. You may have to lift or unscrew this panel to get to the thermostat.)
    • Use a flathead screwdriver to adjust the dial to your preferred temperature in small increments. (If your tank has 2 thermometers, adjust both to the same setting.)
    • Wait about 3 hours and test the water temperature. Feel free to keep adjusting until you find the perfect temperature. [6]
    • If you raised the temperature setting and the water is not getting hotter, there may be another issue (like sediment buildup) that needs attention to get your heater running more efficiently.
  4. The anode rod inside the tank attracts corrosive particles to itself so they don’t damage the interior of the tank. It’s fairly straightforward to inspect and replace your anode rod: [7]
    • Turn off the water supply and the electricity or gas to the heater.
    • Open up a hot water faucet in your home and leave it on.
    • Drain a few gallons from the tank through the drain valve (similar to how you would flush the tank). The water level should be just below the top of the tank.
    • Locate the top of the anode rod on top of the tank—it should look like a hex-head bolt. Some models have a small plastic cover over the top of the rod.
    • Use a socket wrench to unscrew the rod (a long breaker bar may be needed to get enough leverage to loosen it), then lift it out of the tank for inspection.
    • If the rod looks substantially worn or pitted, is coated in mineral deposits, and/or has worn down to less than ½ inch (1.3 cm) in thickness, it needs to be replaced. If it is still in good shape, put it back inside the tank.
    • To replace a worn anode rod: Wrap the threads of the new anode rod with plumbers tape (go clockwise around the threads 3-5 times). Slide the new rod into the top of the tank and turn it clockwise to tighten. Most anode rods cost $30-50.
  5. The pilot light is a small flame inside gas heaters that acts like an ignition to heat up the water. If the light goes out (because you turned off the gas to do maintenance or for any other reason), you’ll have to relight it to get hot water: [8]
    • Lift off the side panel or cover from the tank (there may be an additional layer of heat shielding or insulation to remove after that).
    • Check to see if there is a small flame burning. If there is not, turn off the gas to the heater. Blow into the opening to disperse any lingering gas, open some windows for ventilation, and wait several minutes for any built-up gas to dissipate. If you smell any gas or suspect a leak, do not attempt to relight the pilot and call a professional.
    • Turn the knob on top of the control box to “Pilot” and turn on the gas to the heater.
    • Push the pilot light button to reignite the pilot. Some models require you to hold down a reset button while pressing the pilot light button. (If your heater doesn’t have one, hold a lit match or barbeque lighter up to the pilot access opening.)
    • Continue holding (or press and hold) the reset button for 1 minute.
    • Release the button and check the pilot. If it’s still on, turn the control knob to “On” and replace the side panel.
    • If you cannot get the pilot to restart or are uncomfortable doing it yourself, call a professional plumbing service like Roto-Rooter to do it for you.
  6. While you’re maintaining other parts of the tank, check for drippage or leaks coming from any component of the heater (tank, pipes, connections, etc.). To inspect thoroughly: [9]
    • Turn off the water heater and shut off the cold water supply to the tank.
    • Investigate the fittings on pipes, the drain valve near the bottom of the tank, and the temperature and pressure relief valve.
    • Tighten loose fittings with a wrench. If the TPR valve is leaking, the water may be too hot—adjust the temperature down to relieve some pressure (and stop the corresponding leaks). Sometimes a light tap on the valve pin with a screwdriver handle will clear the valve of grit and allow the valve to reseat, thereby stopping the leak. Leaky TPR and drain valves may need to be replaced if you are unable to stop the leak.
    • If water is leaking through the bottom of the tank, it means the bottom has corroded due to sediment buildup, and the tank needs to be replaced.
  7. The air intake filter prevents dust and debris from entering your water heater and needs to be cleaned at least annually (preferably several times a year). It’s located at the very bottom of the tank. To clean: [10]
    • Locate the filter beneath the tank. It’s a nylon-type filter that wraps around the base.
    • If it’s clogged or dirty, vacuum the debris away to clear it. Leaving debris there will restrict air circulation and make the tank overheat, causing it to shut off.
    • Remove the access panel on the side of the tank above the filter and wipe or vacuum away any dust and debris there, too.
    • If your heater tripped off because of overheating from a clogged filter, press the thermal reset switch behind the access panel. You’ll hear a click to know it’s reset. You can then relight the pilot light (on gas water heaters) and test if your water heater is working again.
  8. Insulating older water heaters makes them more efficient (they take less time to heat up the water) and extends their life (the metal won’t experience as many drastic temperature changes).To insulate your water heater:
    • Turn off the heater and cut a big piece of an insulating blanket to wrap around it.
    • Tape the blanket in place around the heater or have a partner hold it. Mark where to cut holes to access the valves, knobs, and access panels.
    • Line up the holes with their corresponding components and tape the blanket permanently in place.
    • Turn the heater back on and do not set the temperature above 130°F (54°C) to prevent the wiring from overheating. 120 degrees Fahrenheit is the optimal temperature to prevent scalding risk.
    • You can also wrap insulation around the outgoing hot water pipes leading from the tank to prevent heat loss there.
  9. Advertisement
Section 2 of 6:

Tankless Water Heater Maintenance

PDF download Download Article
  1. Turn off the electricity or gas supply to the heater, then shut off the cold water supply valve to the heater and the valve that sends hot water from the heater. Attach a 6-foot (1.8 m) garden hose to a water pump on one end and to the cold water valve on the other. Then, connect a second hose to the hot water valve and place the other end in a 5-gallon bucket of distilled white vinegar. Place the pump line in the bucket as well. [11]
  2. Turn on the pump to begin circulating the vinegar through the heater. Let the pump run for about an hour and a half to break down calcium and other mineral deposits. Then, replace the vinegar in the bucket with cold water and run the pump again to rinse the vinegar out of the heater. [12]
  3. The screen is located in the cold water supply valve where the supply line connects to the heater. With the cold water supply still off, unscrew the housing over the filter to remove it. Simply rinse it with clean water to remove any debris and then replace it. [13]
    • Once the filter is clean and the tank is flushed, open the cold and hot water valves and turn the electricity or gas back on. Let a faucet run for a few minutes to purge any air in the system.
    • Flush your tankless water heater and clean the inlet filter screen at least once per year.
  4. Advertisement
Section 3 of 6:

More Maintenance Tips for Longevity & Efficiency

PDF download Download Article
  1. If you’re not confident in your water heater maintenance abilities, make an appointment to have it all done for you in one session. A professional technician from a plumbing repair company like Roto-Rooter can inspect your tank and anode rod, flush it of sediment, and identify and repair any leaks, drips, or faulty valves.
    • They can also inspect your gas line and connection for potential leaks if you have a gas water heater, which is important for maintaining your safety.
    • Address water heater issues right away. If you notice rusty water, strange noises, or inconsistent water temperature, inspect your heater yourself or call a pro to take a look as soon as you can to prevent further damage.
  2. Many water heaters have a vacation or low-energy mode to conserve energy while you’re gone. If you’re going to be away from your house for several days or more, consider turning on this feature.
    • Simply adjust your temperature dial or thermostat to “Vacation” or “VAC.” Most manufacturers set their vacation temperature to around 50°F (19°C).
    • Some newer models may have a feature where you can set your return date, prompting the water heater to reheat before your return.
  3. Mineral deposits from hard water can cause your water heater to run less efficiently or reliably. If your home has hard water, consider installing a water softener . While this is technically a job you could do yourself if you’re confident in your abilities, water softener installation is typically left to the pros. Most installations take 2-4 hours and cost around $1,800 and up. [14]
    • A water softener will extend the life of your water heater and reduce your energy costs since the heater will work more efficiently.
  4. Advertisement
Section 4 of 6:

When to Repair or Replace a Water Heater

PDF download Download Article
  1. If you notice any of these symptoms or performance issues, your water heater likely needs maintenance outside of your regular annual check:
    • Your water looks cloudy, rusty, or sandy with debris. This means that corrosion in the tank or rusty pipes may be an issue. Run cold water and check to see if there’s cloudiness and discolorization from sediment—if there is, the tank needs to be flushed. If it’s still rusty, then the issue is likely with the cast iron water supply pipes. [15]
    • Your water is not hot or is inconsistently hot. First, check the thermostat and raise it to 120°F (49°C) if it’s not already. If this doesn’t fix the issue, there may be a broken heating element that needs to be replaced by a professional.
    • The heater makes banging or rumbling noises. This usually indicates sediment buildup and may be fixed by flushing the tank. Superhardened or excessive sediment can cause long-term damage if left unattended.
    • There are leaks from the pipes, connections, or valves. These leaks mean there are loose connections or corroded valves or pipes that need to be replaced or patched.
  2. Even with great attention and regular maintenance, all water heaters meet their end someday. Here are the most obvious signs it’s time to replace your water heater: [16]
    • The exterior of the tank is corroding. This likely means the inside is corroding as well and that the tank should be replaced.
    • The tank is leaking from the bottom. This also signifies bad corrosion that’s eating through the tank.
    • It’s been repaired multiple times recently. If you’ve had to schedule repairs several times in the past few years, it may be time for this system to go.
    • The heater is old, and you’re not sure when it was last replaced. Most conventional heaters last 8 to 12 years, while tankless heaters may last up to 20.
    • Dirty water, noises, or temperature inconsistencies don’t improve. While these symptoms don’t always mean replacement is imminent, they might if other fixes and maintenance can’t correct the issue(s).
    • Need an expert to replace your water heater? When it’s wintertime, and your water runs cold, you might not feel like tinkering with your water heater yourself. Schedule a replacement with Roto-Rooter at any time. Their 24-hour emergency service means you’ll have a brand-new water heater right away!
  3. Advertisement
Section 5 of 6:

Key Parts of a Water Heater

PDF download Download Article
  1. Familiarize yourself with these important parts of a water heater to make maintenance easier. Different models will be designed slightly differently, but almost all of them have the following:
    • Water tank to store and heat water (only on conventional water heaters)
    • Heating element or burner (like a pilot light in gas-powered heaters)
    • Thermostat or temperature dial
    • Anode rod inside the tank to prevent tank corrosion
    • Temperature and pressure relief valve (TPR or T&P valve) to prevent excessive pressure buildup
    • Dip tube to bring cold water to the bottom of the tank for heating
    • Drain valve to release water at the bottom of the tank
    • Cold water shut-off valve (found on top of the tank)
    • Gas supply valve (for gas-powered heaters)
Section 6 of 6:

Water Heater Maintenance: Frequently Asked Questions

PDF download Download Article
  1. The most conventional water heater is a storage water heater that holds hot water in a tank to disburse when needed. These can be powered by gas or electricity. Besides these, there are several other types of water heaters (all with their own advantages, disadvantages, and maintenance needs): [17]
    • Tankless water heaters can be gas or electric and heat water on an as-needed basis (rather than storing hot water in a tank).
    • Electric heat pump water heaters draw in heat from the air and amplify it to warm the water stored in its tank.
    • Solar water heaters are powered by the sun and may be installed on the roof or in a yard. There are different types for warm and cold climates.
    • Condensing water heaters are mostly used commercially and can have a tank or be tankless. They pull air and natural gas into a combustion chamber to heat the water.
  2. Yes! Draining or flushing the water heater tank is considered regular maintenance and is doable on your own if you have the right equipment (a hose, a place to drain the water, and a pump for basement heaters) and are familiar with the components of a water heater. In general, the process takes an hour or 2 (including prep work and refilling the tank after flushing).
    • If you don’t know how to (or just don’t want to) flush your heater yourself, a professional plumber or heating repair person can do it for you.
  3. Annual preventive maintenance usually costs $100-500 per year and includes services like a tank flush, anode rod check and replacement, valve inspection, and more tune-ups. The final cost depends on factors like the type of water heater you have, how much work needs to be done, the cost of labor and parts, and whether you’ve called for a one-off inspection or you’re on an annual maintenance plan. [18]
  4. Call a professional when there’s a problem that regular maintenance can’t solve, when the entire heater needs to be replaced, or when you’re concerned there may be a gas leak. For example, if you’ve flushed the tank and checked the thermostat, but the heater still isn’t making hot water, call a pro for a more in-depth inspection.
    • You can also call a pro for basic maintenance and “easy” repair work that you don’t feel comfortable doing yourself. It’s better to pay for preventative maintenance on a hot water heater than to repair a mistake!
  5. Advertisement

Expert Q&A

Ask a Question
      Advertisement

      Tips

      Submit a Tip
      All tip submissions are carefully reviewed before being published
      Name
      Please provide your name and last initial
      Thanks for submitting a tip for review!

      Warnings

      • Wear protective gloves and goggles while working on your water heater to protect yourself from spurts of hot water or other debris.
      • Never go barefoot or wear open-toe shoes or sandals when working around a water heater. Hot water can spray out of the T&P valve and scald your feet.
      • Open doors and windows or turn on fans to ventilate the area around your water heater while you work if it’s powered by gas.
      • Always turn off electric heaters, move the control knob to “Pilot” for gas heaters, and turn off the cold water supply valve before beginning any maintenance.
      • If possible, wait several hours after turning off the heater to begin maintenance to let the water cool to safe temperatures.
      Advertisement

      About This Article

      Thanks to all authors for creating a page that has been read 84 times.

      Did this article help you?

      Advertisement