How to Flush Water Heater with Vinegar

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Water heaters are essential for homes during cold seasons. We have to carry out household chores like dishwashing and regular cleaning despite the freezing climate.

As such, you wouldn’t imagine life without water heaters. For better maintenance of your unit, this article will share how to flush water heater with vinegar.

Water heaters are tall cylindrical drums usually installed in the laundry rooms or the basement. They heat water, and pipes supply it to sinks, baths, showers, and various taps for home use.

Before you learn how to dissolve sediments in water heater with vinegar, take a look at how the unit works.

How to Flush Water Heater with Vinegar

How to Flush Water Heater with Vinegar

How a Water Heater Works

A water heater tank is made of an inner shell made of steel and the outer covering. Most tanks have a capacity of around 50 to 60 gallons.

The device operates by heating the dense water at the bottom. Once the dense water is heated, it rises and exits through an outlet for use.

Cold water enters the tank through a dip tube that extends to the bottom. The water is heated by the element or the gas burner and rises on top to allow more dense water.

The unit has a thermostat that controls the temperature by turning on or shutting off the system. Once pressure builds up, a pressure release valve on top allows excess air out. The mechanism enhances efficiency.

The unit has a sacrificial anode made of aluminum or magnesium metal on the top of the tank. Its purpose is to separate rust-causing ions from water.

At the bottom, there is a drain valve that helps to drain water during maintenance or repair.

Why Do We Flush Water Heater Tanks

Water contains some natural minerals like calcium. Additionally, there might be grit and sand within the pipes. When these minerals are heated, they separate by settling at the tank’s base or around the walls.

Although the sacrificial anode is installed to protect the tank, some minerals may be too high to separate.

With time they build up around the element and the tank. As a result, they reduce the heater efficiency. Secondly, the steel tank may rust, and third, they discolor the water.

Once the tank surface is coated with the minerals, you might notice the following signs;

  • Increased energy bills because the heater works harder.
  • The heater takes longer than usual to heat the recommended volume of water.
  • Leaking tank due to corrosion.
  • Discoloured water

Read: Quiet baseboard heaters

How to Flush Water Heater with Vinegar

What Kind of Vinegar Should You Use to Flush the Water Heater?

Many homeowners ask what kind of vinegar to clean water heater? I recommend apple cider vinegar because its acid level dissolves sediments quickly.

Steps How to Flush Water Heater with Vinegar

To effectively flush your water heater, you’ll need to carry out two processes. Read below;

a) First Process: Draining the Tank

Step 1: Turn off the water heater by flipping the circuit breaker. If your heater is gas-fuelled, close the gas valve.

Step 2: Close the cold-water supply valve.

Step 3: Locate the drain valve at the bottom of the tank

Step 4: Connect a garden hose to the drain valve and direct it to the sink or a bucket.

Step 5: Open the drain valve and let the water drain completely. Ensure the pressure release valve is open to allow air in and fasten the process.

Step 6: Close the drain and pressure release valve once the tank is empty.

Read: How do you remove water from a baseboard heater?

How to Flush Water Heater with Vinegar

b) Second Process: Adding Vinegar and Flushing

Step 1: Locate the sacrificial anode at the tank’s top. A large bolt usually secures it.

Step 2: Use a plumbing wrench to loosen the bolt and remove the anode rod. You create a space to pour in your vinegar by removing the rod.

Step 3: Set a funnel at the sacrificial anode opening.

Step 4: Pour around 10 litres of apple cider vinegar into the tank. Vinegar in the water tank will start weakening the sediments right away.

Step 5: Replace the sacrificial anode to cover the opening.

Step 6: Open the cold-water supply valve and let it fill the tank for around 10 minutes. The water will stir and circulate the vinegar for effectiveness.

Step 7: Leave your heater tank for 24 hours to allow the vinegar to weaken all the built-up minerals. In the end, all sediments will have detached from the steel tank. However, notify the family members to avoid confusion.

Step 8: After 24 hours, connect your garden hose to the drain valve and lead it to a safe disposal area. Note this water with vinegar is not safe for watering the plants.

Step 9: Open the valve and let the water-vinegar solution drain. You’ll notice sediments at the disposal area. If deposits clog the hose, massage it to break them.

Step 10: Open the cold-water valve and flush the tank until the water turns clear.

Step 11: Close the drain valve and disconnect the garden hose. Fill your tank with cold water and turn it on to confirm it’s fully functional.

Read: How to drain a water heater without drain valve

FAQs on your Hot Water Heater

Is it Safe to Put Vinegar in Your Hot Water Heater?

Vinegar is very safe in your hot water heater tank provided you flush the tank well afterward. By choosing apple cider vinegar, you’ll eliminate mineral build-up into the tank, and you’ll notice the following benefits;

Faster heating
Minimized corrosion
Reduced energy bills

How Long Does it Take to Flush a Water Heater?

On average, it can take around 20 minutes to flush a 50-gallon water heater. If there was much mineral build-up in the tank, you might need more time because they clog the drain hose. At that point, you’ll need to keep massaging the hose pipe to break them.

How Do I Prevent Calcium Build up in My Water Heater?

The best way to prevent calcium from building up in your water heater tank is by adding a water softening system. The system separates minerals from the water before getting into the tank. Secondly, regularly flush the water heater with vinegar if you use hard water at your home. By maintaining the unit, you increase its lifespan and efficiency.

Read: Water heater disposal cost