Flush your water heater annually!

TONI DEE
Jul 5
3 min read

I love doing DIY home maintenance jobs on weekends.

This weekend I flushed my water heater.

Home ownership can be expensive, but there are many good YouTube videos to assist with those projects.

You may ask:

Why flush your water heater? And how often does it need to be done?

Flushing your water heater is important for maintaining the performance, safety, and longevity.

You do it to remove sediment buildup. Over time, minerals (like calcium and magnesium) and debris from your water supply settle at the bottom of the tank.

This buildup can:

Reduce heating efficiency
Cause popping or rumbling noises
Lead to clogs or damage
Make your heater work harder (raising energy bills)
Sediment covers the heating element, causing it to work harder, use more energy, and fail prematurely.
Affect water quality causing rust, discoloration, and foul odor.

Some water heater warranties require routine maintenance, including flushing. Neglecting this could void the warranty.

How often? Annually is generally recommended, but do it more often if you have hard water.

If it has been awhile since your water heater has been flushed, plan on doing several small flushes in the course of this project, it could take awhile. After it has been thoroughly flushed and free from sediment, future flushing should go pretty quickly, as long as you do it regularly.

You can do it yourself, I do.

Watch several videos on YouTube, since they each have different tips and tricks.

Great! Here's a step-by-step guide to flushing your water heater safely and effectively. This applies to most standard tank-style gas or electric water heaters.

🔧 What You’ll Need:

Garden hose
Bucket (optional, for checking water quality)
Flathead screwdriver (for gas models)
Work gloves & safety glasses (recommended)

⚠️ Step 1: Turn Off the Heater

Gas heater:

Set the thermostat to “Pilot” or turn off the gas entirely.
For safety, wait about an hour to let the water cool slightly. I like to turn it off the day before so the water is cool enough to put directly on my plants.

Electric heater:

Turn off the power at the breaker box. Never drain a live electric heater — it can damage the heating elements.

🚿 Step 2: Turn Off the Cold Water Supply

Locate the cold water valve at the top of the heater and turn it off. This stops more water from entering the tank.

🧯 Step 3: Attach a Hose to the Drain Valve

Connect a garden hose to the drain valve at the bottom of the heater.
Place the other end outside or into a floor drain. (A bucket works if you want to inspect the water.) I use a long hose and run it into my front yard to recycle into my garden.

🚰 Step 4: Open the Drain Valve

Carefully open the drain valve. Water should begin flowing out.
To help it drain faster, open a hot water faucet somewhere in the house (like a bathroom sink).

Sometimes you will need to open the pressure- relief valve as well.

💧 Step 5: Flush the Tank

After the tank is empty, there are several methods to break up the sediment and flush it out. You can turn the cold water supply in quick blasts then back on for 1–2 minutes.

This “flushes” out any leftover sediment. Let the water drain out again.
Repeat until the water runs clear and no sediment is present.

If it has been a while since flushing your water heater - you may be in for a long process to get the caked up minerals out.

Keep doing it until there are no more solids and the water is clear.

🔄 Step 6: Close the Drain Valve & Refill the Tank

Close the drain valve tightly.
Turn the cold water back on to refill the tank.
Leave the faucet open until water runs smoothly (removing trapped air), then turn it off.

🔌 Step 7: Restore Power or Gas