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How to Maintain a Water Heater

Hot water is a modern necessity, but replacing your water heater can be expensive. Proper preventative maintenance on a water heater can ensure that your unit lasts, saving the hassle and expense of a premature replacement.

Benefits of Preventative Hot Water Heater Maintenance

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Performing preventative maintenance on your water heater usually improves the unit’s longevity and performance. When your water heater operates at peak efficiency, it uses less energy, translating into lower electricity or fuel costs. Noticing and fixing minor issues while servicing your unit can prevent big problems and save you money on repair and replacement costs, and preventative maintenance increases safety levels in your home by preventing electrical and gas issues. Proper water heater care also removes sediment buildup and corrosion to improve the taste, feel and overall quality of your water.


Below are some common water heater parts that require maintenance or are often the source of repair issues:


  • Cold water inlet
  • T&P Discharge Pipe
  • T&P relief valve
  • Anode rod
  • Drain valve
  • Hot water outlet
  • Pilot assembly
  • Gas valve
  • Thermopile
  • Heating element (electric water heaters)
  • Thermostat (electric water heaters)

Safety First

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With a little care and maintenance, you can keep your gas and electric water heaters working efficiently. If you’re not comfortable working with gas or electricity when caring for your water heater, however, call a professional. 


Caution

Always wear gloves, goggles and other protective clothing while performing maintenance on your water heater.


Water Heater Maintenance Guide

Checking the T&P Valve

Both gas and electric water heaters have a safety device called a temperature and pressure relief valve, or T&P valve for short. In the event the tank is overpressurized, the relief valve opens and releases the pressure. If the valve doesn't operate correctly, the tank can overpressurize and explode. Maintenance should be performed on the T&P Valve once a year by the consumer and should be inspected by a professional every 5 years.

Step 1 - Shut Off the Unit

Turn off the electricity to the water heater or turn off the gas to extinguish the pilot light. Shut off the cold-water inlet to the water heater.


Step 2 - Pull the Trip Lever

Position a bucket to catch water from the pressure relief valve, and then pull the trip lever on the valve to release the water. Be careful as the water can be very hot. If you don't see any water coming out of the t&p valve, drain the tank and replace the valve.


Step 3 - Replace the Valve

To replace the valve, remove the discharge pipe, and unscrew the valve from the water heater. Note the stem length and buy an exact replacement. Screw the new valve into place, tightening with a wrench. Reattach the discharge pipe, turn on the water, purge the air and either reconnect the electricity or restart the pilot light according to the manufacturer's instructions.

Flushing the Tank

Sediment buildup in the tank can reduce your water heater's energy efficiency and also clog your water lines. Avoid these problems with preventative maintenance, and increase the life of your unit by flushing the tank each time you check the pressure relief valve.

Step 1 - Turn Off the Unit

Turn off the electricity to the water heater or turn off the gas to extinguish the pilot. Shut off the cold-water inlet to the water heater. Open a faucet and run the water until it goes cold.


Step 2 - Connect a Hose

Connect a garden hose to the tank's drain valve. Place the hose’s draining end in an area that can handle several gallons of hot water.


Step 3 - Open the Drain Valve

Turn off the water, open the drain valve and let the tank drain completely and letting the water run until it is clear and sediment is not coming out ensures that you've removed all the sediment you can.


Step 4 - Close the Valve

Close the tank drain valve, disconnect the hose from the valve and close the pressure relief valve. Open all the hot-water spigots in the house to remove any air that may have been introduced into the system. Close the spigots once air stops coming from the faucet. and turn on the cold-water inlet to the tank.


Step 5 - Turn the Unit Back On

Close each hot-water spigot as water begins to flow from it. After closing all the spigots, Turn on the electricity to the water heater, or turn the gas switch to run. Following the instructions on the water heater, the pilot light may need to be relit.

Adjusting the Temperature

Water that’s too hot or too cold is one of the most common issues with water heaters. Fortunately, though, this water heater maintenance issue is one of the easiest to service simply by adjusting the thermostat.

Step 1 - Turn Off the Unit

Turn off the electricity to the water heater. If this is a gas water heater, skip to step 3.


Step 2 - Open the Access Panel 

Use a screwdriver to remove the access panel that’s typically found on the front of your water heater. Remove the panel carefully, making sure to avoid wiring and components.


Step 3 - Adjust the Temperature 

Locate the thermostat temperature dial, control knob or LCD display. Once you determine the current setting, adjust the temperature to fit your household needs, which is typically no higher than 120 degrees Fahrenheit. Remember to be careful when adjusting your unit’s thermostat. Setting the temperature too high will create dangerous, scalding hot water, and setting it too low can allow bacteria to grow.



Step 4 - Replace the Cover

Replace the cover, and turn on the power to the water heater. Monitor the new temperature and make adjustments as needed by following these steps again.

Checking the Sacrificial Anode

Sacrificial anode rods protect the inside of water heater tanks from a process called galvanic corrosion. Because water heater tanks are made from metal that’s susceptible to corrosive elements in water, the anode sacrifices itself to protect the tank. The anode freely gives up ions so electrolysis does not dissipate the steel of the tank.

Step 1 - Turn Off the Unit

Turn off the electricity to the water heater or turn off the gas to extinguish the pilot. Open a facet to run the water cold.


Step 2 - Locate the Rod

Locate the sacrificial anode rod. This water heater component typically hangs down into the tank from the top.


Step 3 - Drain some water from the water heater.

Shut off the incoming cold water. Attach a garden hose to the drain valve. Open the drain valve and let a few gallons of water drain from the water heater.


Step 4 - Remove the Rod

Using an electric impact wrench, use a 1 1/16 deep well socket to remove the anode. 


Step 5 - Inspect the Rod

Perform a visual inspection. A rod in good working condition should be smooth and around a half inch in diameter. If the sacrificial anode rod shows signs of deterioration or has several inches of exposed core wire, replace it.


Step 6 - Install a New Rod If Necessary

Determine the type of sacrificial anode rod your water heater needs, typically magnesium, aluminum or zinc. Install the new part in place of the old one, making sure to properly align all parts and secure all threaded screws.



Step 7 - Turn the Unit Back On

Refill the water heater, purge all the air from the tank by running a faucet for several minutes. Turn the power on or relight the pilot light, and check for leaks.

Insulating the Pipes and Unit

Part of DIY preventative water heater maintenance is weather-proofing your unit to reduce freezing risks in colder climates. Proper insulation around the pipes and tank does this and more, preventing heat loss for improved energy efficiency.

Step 1 - Measure and Prep

Measure the pipes, and choose insulation materials like foam sleeves that precisely match the dimensions you need. Prepare the insulation material according to instructions.


Step 2 - Install Insulation and Tape Seams

Install the insulation materials, starting with the water heater tank and working your way out. Use foam tape to secure the insulation so that there are no gaps or overlapping areas.

Gas Water Heaters: Lighting the Pilot

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With the gas valve knob set to pilot, press and hold in the knob and push the igniter button one time a second for up to 90 seconds. The light will blink when it’s lit and you should see a small flame through the view pane. Set the temperature to 120 degrees Fahrenheit.


Caution

Read and follow your manufacturer’s lighting instructions for more detailed instructions on lighting the pilot.


Good to Know

Newer water heater models have a smaller pilot light, which may be hard to see. If so, darken the room and look carefully through the sight glass in order to see the pilot light.


A gas water heater may produce condensation the first time it is lit. You may hear dripping sounds or see a small puddle of water in the drain pan. This condensation is normal and goes away once the water heater reaches its normal operating temperature.

Electric Water Heaters: Before Connecting Electric Power

Follow these steps before connecting the power to your electric water heater.

Step 1

The most common problem with electric water heaters is turning the power on before the tank is completely full of water. If this happens, the upper heating element will burn out, and you’ll have no hot water until the upper element is replaced.


Step 2

To replace the top or bottom heating element, disconnect power to the unit and drain the water heater tank. Disconnect the wires from the element and loosen it using an element wrench. Unscrew the element and pull it straight out. Insert the new element in its place and tighten using the element wrench. Reconnect the wiring and prepare to refill the tank.


Step 3

Open a hot-water faucet all the way and let the water run for 3 minutes. This ensures all of the air has been removed and the tank is completely full of water. When the tank is full, turn the power on. If you don't have hot water after 2 hours, check to make sure the unit is getting the correct voltage. (See the unit’s label for power requirements.) No electric power or the wrong voltage causes many electric water heater problems, so you may need an electrician to solve wiring or power problems.

Leaks and Drips

Follow these instructions on how to handle leaks and drips.


When servicing your water heater, you may find that you’re getting leaks or drips. Most leaks are caused by faulty water supply connections, so use good materials, proper techniques and check your work carefully. Compression fittings are easier to install for DIYers than copper pipes, which need to be soldered.


Drips from the temperature and pressure (T&P) relief valve discharge pipe usually mean a thermal expansion tank is needed or your water pressure is too high.

Step 1 - Shut Off the Unit

Turn off the electricity to the water heater or turn off the gas to extinguish the pilot light.


Step 2 - Pull the Trip Lever

Position a bucket to catch water from the pressure relief valve if it doesn’t have a discharge pipe, and then pull the trip lever on the valve to release the water. This will flush any material that could be stuck in the seal. Be careful as the water can be very hot. If you don't see any water coming out of the t&p valve, drain the tank and replace the valve. If the valve continues to drip and you have proper water pressure and a correctly charged expansion tank, Replace the t&p valve.


Step 3 - Replace the Valve

To replace the valve, remove the discharge pipe, and unscrew the valve from the water heater. Note the stem length and buy an exact replacement. Screw the new valve into place, tightening with a wrench. Reattach the discharge pipe, turn on the water and either reconnect the electricity or restart the pilot light according to the manufacturer's instructions.

Frequently Asked Hot Water Heater Maintenance Questions

How do you maintain a tankless water heater?

Caring for a tankless water heater ensures a long lifespan. Just like with a regular water heater, these appliances need to be descaled and inspections. You should also keep watch on the inlet filter regularly to keep it free of debris.



What’s a good annual water heater maintenance checklist?

Servicing your water heater each year helps prolong its life and increase energy efficiency. Care for your unit by checking these common issues annually:

  • Check for leaks.
  • Flush the tank.
  • Test the temperature and pressure relief valve.
  • Inspect the sacrificial anode.
  • Clean air intake vents.
  • Check the venting system.
  • Insulate the pipes and tank.
  • Check thermostat settings.
  • Inspect electrical connections and tighten if necessary.
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