How to Drain Your AO Smith Water Heater: A Step-by-Step DIY Guide

Ugh, nothing signals a potential plumbing disaster quite like a grumpy, gurgling water heater. Think about it – sediment build-up, reduced efficiency, the looming threat of leaks… not exactly the relaxing soak you were hoping for! But before you panic-call a plumber, let’s empower ourselves. Draining your AO Smith water heater is a surprisingly manageable DIY project. And trust me, not only will your water heater thank you, but your wallet will too!

Drain Your AO Smith Water Heater

Before we dive into the steps, let’s explore why draining your AO Smith water heater might be necessary.

  • Sediment Buildup: Over time, mineral deposits can accumulate inside your water heater, reducing its heating efficiency and potentially leading to malfunctions. Regular draining helps remove this sediment build-up, keeping your water heater running smoothly.
  • Annual Upkeep: Just like giving your car a tune-up, draining your water heater is a recommended annual maintenance task. It’s a proactive approach to prevent future problems.
  • Repair Prep: If your AO Smith water heater needs a component replaced, draining is essential to prepare for the repair work.
  • Replacement Time: Bidding farewell to your old water heater? Draining is a crucial first step before removing the unit for replacement.

Safety First: Your Essential Checklist

Safety is paramount when working with plumbing systems. Here are some non-negotiables to keep in mind before tackling this project:

  • Power Down: Safety first! Turn off the power supply to your water heater. For electric units, locate the breaker box and flip the appropriate switch. For gas models, find the gas control valve and turn it to the “off” position.
  • Beware of Hot Water: Water heaters store heated water. Allow the water to cool down completely before draining to avoid potential scalding. How long this takes depends on the size of your water heater and recent usage. Touching the tank itself can be a good indicator of water temperature.
  • Pressure Relief: Water heaters contain pressure relief valves. These valves are designed to release pressure if it builds up to unsafe levels. To prevent unexpected water surges during draining, open the pressure relief valve briefly (consult your owner’s manual for specific instructions).
  • Gear Up: Protect your hands with gloves and wear safety glasses to shield your eyes from any potential water splashes.
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Tools You’ll Need to Get Draining

Tools You'll Need To Get Draining

Now that safety is assured, let’s gather the tools you’ll need for a smooth draining process:

Garden HoseA standard 5/8 inch diameter garden hose will do the trick.
BucketA bucket will be helpful to catch the initial rush of water when you open the drain valve.
Wrench or ScrewdriverThe type of tool you’ll need depends on your specific AO Smith water heater model. Consult your owner’s manual for details.
Optional: Plumber’s TapeIf you plan to reuse the drain valve after draining, consider having some plumber’s tape on hand to ensure a secure connection.

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Let’s Drain! A Step-by-Step Guide

Ready to tackle the drain? Here’s how to get the job done:

  1. Find Your Shut-Off Valve: Locate the cold water supply shut-off valve leading to your water heater. It’s typically positioned above the heater on a nearby water pipe.
  2. Cut the Power: Remember those safety precautions? Double-check that you’ve turned off the power supply to your AO Smith water heater. It’s better to be safe than sorry!
  3. Hose Connection: Securely attach your garden hose to the water heater’s drain valve, usually located near the bottom of the unit. Plan ahead – where will the water drain to? A suitable outdoor area or a floor drain is ideal to avoid water damage indoors.
  4. Open the Drain Valve: Now it’s time for action! Using your wrench or screwdriver, carefully open the drain valve. Begin with a partial opening to regulate the water flow and prevent any unexpected water bursts.
  5. Let the Air Flow: To help speed up the draining, open a hot water faucet somewhere in your home. This allows air to enter the system, facilitating the flow of water out of the drain.
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Pro Tip: Flushing for Extra Cleanliness

While not always necessary, you may opt to give your water heater a quick flush during the draining process to remove stubborn sediment. Here’s how:

  • Open the Supply (Briefly!): With the drain valve still open, briefly turn on the cold water supply. This will stir up sediment at the bottom of your tank. Only do this for a couple of seconds, then close the water supply again.
  • Caution: Expect the water draining from the tank to become discolored during and immediately after flushing. Avoid running faucets elsewhere in your home until clear water is flowing from the drain hose.
  • Assess the Need: Check the water draining from your heater to see how much sediment was flushed out. This provides valuable insight into the state of your heater.

Wrapping Things Up: Closing the Valve and Restoring Operation

Once the water drains to a trickle, it’s time to wrap things up:

  • Close the Drain: Securely tighten the drain valve. If you removed the valve entirely during draining, use plumber’s tape to ensure a water-tight seal when replacing it.
  • Remove the Hose: Carefully detach the garden hose from the drain valve.
  • Close the Hot Water Faucet: Close the hot water faucet you opened earlier to promote airflow.
  • Open the Water Supply: Turn the shut-off valve to the water heater back to an open position, allowing the heater to refill with water.
  • Restore Power: Depending on your type of water heater: turn the gas control valve (gas water heaters) back to “on” and follow the specific instructions from your AO Smith Owner’s Manual to relight your pilot light. For an electric water heater, flip the circuit breaker back to the “on” position.
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Troubleshooting and Calling for Backup

  • Stuck Drain Valve: If the valve refuses to budge, it could signify a buildup of sediment or corrosion inside the valve. In this case, it’s wiser to call a professional plumber to avoid further damage.
  • Persistent Leaks: Should a leak persist even after tightening the valve or connections, immediately shut off the water supply to your water heater and contact a plumber.

Staying on Top of Water Heater Maintenance

Regular draining is just one piece of the water heater maintenance puzzle. Remember these additional tasks for optimal water heater health:

  • Checking the Anode Rod: This rod helps protect against corrosion within your tank and is recommended to be inspected every few years.
  • Testing the T&P Relief Valve: This safety valve is vital for pressure regulation and should be tested annually. Refer to your AO Smith Owner’s Manual for detailed instructions.

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I am a mechanical engineer and love doing research on different home and outdoor heating options. When I am not working, I love spending time with my family and friends. I also enjoy blogging about my findings and helping others to find the best heating options for their needs.