Hot water heaters are often tucked away in a corner as they quietly go about doing their job. It's easy to forget about them, but there are a few maintenance tasks that should be performed to keep them running in tip-top shape. When properly maintained, a tank-style water heater can exceed their average service life of 8 to 10 years.
This article will cover the regular maintenance tasks recommended to keep your water heater running efficiently. Each manufacturer has its own checklist of recommeded periodic maintenance tasks, so it's always a good idea to check your owners manual for specifics.
Water Heater Maintenance Schedule
We recommend marking your calendar with the following water heater maintenance tasks to ensure that they are completed on a timely basis:
Every Two Months
Getting into the practice of inspecting your water heater every couple of months can help you notice small changes. Here's what to look for:
- Check for water leaks, either at plumbing joints or the tank itself.
- Check all plumbing joints for excessive or unusual corrosion.
- For gas-powered heaters, check the condition of the flex hose and any couplings (including smelling for gas leaks), and make sure no flammable materials are near the area of combusion.
- Turn on a nearby hot water tap and listen for unusual sounds (especially hammering or crackling). Unusual sounds might indicate a more serious water heater problem.
Every 6 Months
Flush the water heater's tank by draining a few gallons of water from the tank through the drain valve. This will remove any sediment that has built-up inside the tank. Here's How.
Test the Temperature and Pressure Relief Valve to make sure it's in good working order. Here's How.
Remove and inspect the anode rod once the water heater is two to three years old. Some pitting and surface corrosion is normal and to be expected, but if you see large chunks of metal coating missing from the surface it's a good indication that the anode rod should be replaced. Here's How.
How to Flush Your Water Heater
One of the most important maintenance tasks is to flush your water heater of sediment. We recommend flushing your tank ever six months, especially if you live in an area prone to hard water. Although some areas may be able to get away with an annual flushing.
Flushing your water heater's tank involves draining a few gallons of water through the drain valve. This will draw off sediment (minerals and other minute solids that are found in all water systems) which normally accumulates at the bottom of the tank.
Sediment impairs the performance and shortens the service life of water heaters. However, when flushing is done on a regular basis, it's actually possible to extend the heater's service life. In addition, draining the hot water tank allows for necessary repairs to be completed.
WARNING: Water heaters are typically factory-set to heat water to 125° F, which is hot enought to inflict first degree burns on contact. When turned to the maximum temperature (which can be between 160° and 190° F) serious injuries can result, even from indirect contact with the water. Always take precautions to avoid coming into contact with heated water.
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Step-by-Step Flushing Procedures
Turn Off the Power - The first step is to turn off power to the water heater (gas at the on/off control knob, electric at the circuit breaker box). Keep in mind that the water inside the tank is hot and will remain so for quite some time, even after the power has been turned off. If possible, it's best to use some of the hot water or to wait several hours to allow the water in the tank to cool before proceeding.
Turn Off the Water - Once the water has cooled, turn off the water supply at the cold water shutoff valve.
Open a Faucet - Next, open a hot water faucet in the house (leave it open). This will allow air to enter the tank as it empties.
Connect a Hose - Securely connect a garden hose to the drain valve located near the bottom of the water heater. Make sure that the hose is long enough to reach a drain, sump pit, or outside. Open the drain valve.
Drain a Few Gallons - After a few gallons of water has drained, collect some of the water in a bucket or run it through a screen to check the amount of sediment you've collected. If very little sediment is found, and the water flowing from the tank is otherwise clear, flush several more gallons and then close the drain. If you flush a few gallons from your tank every six months you typically won't have a lot of sediment.
While flushing your water heater you may notice heavy white sediment. If you do, it's an indication that the anode rod is deteriorating and it should be inspected. See below to learn how to inspect and replace an anode rod. This procedure should be done before refilling your tank.
The only time it should be necessary to completely empty the tank is when the drain valve needs to be replaced, or the water heater itself needs replaced. To do this, follow the same procedures as with flushing, but leave the drain valve open until the tank has completely drained.
If Heavy Sediment is Found - If after draining a few gallons you still find quite a bit of sediment, continue to drain the tank. Check every 5 to 10 gallons to see if the water is free of sediment. You can turn the cold water supply back on to help stir up and remove any sediment still in the tank. Continue doing this until the water flowing from the tank is clear and sediment-free.
Make Repairs - Since you've drained at least a few gallons of water from your tank, this is a good time to complete any other repairs. Replacing the T&P valve, anode rod, and heating elements all require at least partially draining the tank.
Refill the Tank - Close the drain valve and turn the water supply back on. NEVER turn the power to your water heater on until the tank is completely full. Check the hot water tap you left open, and when you see water coming out of it at a full stream, you know your tank is full and you can turn the power back on.
Watch the Video
We highly recommend installing a sediment filter on your incoming water line. It'll filter the water before it enters your water heater's tank. Although these filters will not eliminate the need to flush your tank, they will prolong the time between flushings. This article is focused on tankless water heaters, but sediment filters are beneficial for tank-style heaters as well.
How to Replace an Anode Rod
Checking and replacing the anode rod is a critical part of performing water heater maintenance. When metal and water mix, the winner is always water; and when water is heated, the process is accelerated. Sooner or later metal corrodes and begins to breakdown the steel tank, eventually causing it to leak. When your tank springs a leak, there isn't a way to repair it, your only solution is a new water heater.
The anode rod helps protect the tank by sacrificing itself. This long, narrow, solid pipe is suspended inside the tank by a screw-in fitting at the top. It's typically made of aluminum, magnesium or zinc, or a combination of these metals. All three metals are particularly susceptible to the corrosive process.
Anode rods work because corrosion tends to feed on the most vulnerable targets first. The anode rod, which serves no other purpose, will suffer the corrosion that the steel sides of the tank otherwise would, thereby extending the service life of the tank.
However, an anode rod will eventually completely corrode and dissolve. When this happens it's no longer able to perform it's purpose and your tank will be in the line of fire.
Anode rods typically have a useful life expectancy of 4 to 6 years. But keep in mind, if the water is particularly hard, they will breakdown faster. But, they'll also last longer if a lower water temperature is used. However, be careful, too low of a temperature is a safety concern.
You should begin inspecting your anode rod when your water heater is 2 to 3 years old, then check it at least annually there after. When flushing your tank, you'll sometimes see heavy white sediment, which could be an indication that your anode rod needs to be replaced.
Step-by-Step Anode Replacement
Turn Off the Water - Next, you'll need to close the cold water shutoff valve, and open a nearby hot water tap to allow the pressure inside the tank to equalize.
Drain a Few Gallons - Draw off a few gallons of water through the drain valve, in order to clear any remaining water from the hot water pipes that are above the level of the top of the tank. The tank itself does not need to be completely drained. See above for detailed instructions.
Locate and Loosen the Anode Rod - The anode rod is threaded into the top of the water heater tank. It may be located under a cap that'll need to be pried off. Once you located it, use a wrench or socket to turn it counter-clockwise until it clears the threads. Be prepared, a small amount of water may gush-up from the opening.
Remove the Anode Rod - Carefully remove the anode rod by lifting it straight up. Try to keep from knocking it against the inside of the tank or the sides of the opening. The rod may be very fragile and parts may break loose and fall inside the tank, only to become more sediment that'll eventually need to be flushed.
Inspect the Anode Rod - It's common to see some pitting and surface corrosion, this is okay. But if you see large chucks of metal coating missing from the surface, or portions of the rods length missing entirely, the anode rod should be replaced.
Install the Anode Rod - Whether your anode rod is still in good condition or you need to purchase a new anode rod, it's time to put it back in place. Wrap the threads with Teflon tape and carefully slide the rod back into the hole on the top of the heater. Then tighten it securely.
Refill Tank - Open the cold water supply valve, and allow the water level in the tank to top off (indicated when water flows freely from the nearby open hot water tap). Turn the tap off, and turn the power to the water heater back on.