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Tankless Water Heater Maintenance Guide

Tankless water heaters have become increasingly popular due to their excellent productivity and ability to minimize energy loss. They are relatively easy to care for, but there are some things you should know if you own one or plan to in the future. So what are some of the best ways to maintain your tankless water heater and prolong its useful life? 

Tankless water heater maintenance is fairly straightforward. In addition to checking the filters regularly, you should flush the system by removing the valve covers, connecting a hose to the valves, and flushing them out with distilled vinegar. Afterward, reassemble everything and turn it back on.

If you’re looking for ways to prolong the life of your water heater, then you couldn’t be in a better place. Read on for tips on how to keep your tankless water heater in tip-top condition. 

Must-Know Tankless Water Heater Maintenance Tips

While tankless water heaters have several advantages, they are quite costly, hence the need for proper maintenance. 

Let’s take a look at some must-know tips for making your investment worthwhile.

Get Your Tankless Water Heater Ready for Internal Maintenance

You’ll want to check the filters inside when performing maintenance on your tankless water heater. Though this isn’t very difficult, I’ll advise you on how to do it as safely and effectively as possible. 

As explained in this helpful video from Tankless Guy, a couple of simple preparation steps can make inspecting and servicing your filters a much more streamlined process. 

Preparing your tankless water heater for filter inspection can help you avoid the following: 

  • Burns
  • Outages
  • Flooding
  • Equipment damage

Read: What Is One Disadvantage Of A Whole House Tankless Water Heater?

Turn Off the Power

Before you do anything, you must ensure the water heater is ready for inspection and potential servicing. The first step you’ll need to take is to turn off the power. Like working with any electrical appliance, especially when water is involved, you need to ensure the power is off when you look at it. 

Some of the reasons you should turn off the power when you are working on your tankless water heater include the following: 

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  • You will be around wires, which increases the chances of electrocution if you aren’t careful.
  • Power surges can occur if you don’t turn off the power source when working on heavy-duty equipment like a tankless water heater. 

Read: Why Water Heater Leaking From Bottom?

Shut Off the Water Supply

Just like power, you should ensure the water is not on when performing internal maintenance on your water heater. While you will need the water and power to flush the system, the opposite is true when you perform maintenance inside the unit. 

Turning off the water is simple and can save you some major headaches. Some maintenance that requires you to run off the water includes:

  • Changing the air filter. 
  • Replacing or cleaning the water filter. 

Take my advice, and you’ll be on your way to changing the filters safely and effectively

Prepare the Surrounding Area for Changing the Filters

Before doing anything else, you should prepare the unit for inspection and potential filter replacement. You can prevent large messes and make it go as smoothly as possible by preparing the area before you begin changing filters.

Here are some things I recommend:

  • Be sure to clear out the area and lay down some towels under the unit.
  • Have some rags ready to wipe excess dust or debris from the filters.
  • Keep your backup filters close in case you need to replace them rather than clean them. 

Read: Why Water Heater Not Heating Well? – Troubleshooting Guide

Flush the Out the Unit

One thing you should do when you’re trying to keep your tankless water system in good shape is flush the unit. This process might sound complicated, but the good news is you can do it yourself, as long as you adhere to some safety precautions and use the right tools. 

When performing maintenance on your water heater, it’s vital to flush the unit. But what are some of the best tips for doing this correctly?

Leave the Water and Electricity On

Leaving the water and power on for this step is important and for good reason. Unlike changing the filters, you’re actually going to want to keep the water and electricity running while you work so you can successfully flash the system. 

Turn Off the Valves Before Starting

This step involves shutting off the valves. You must have them pre-installed to perform the maintenance, so ensure that you do it before you start the flushing process. Once you have the valves shut off, you can add your preferred flushing solution.

Always Use Food Safe Products

Because you are going to use this water for daily needs, you need to make sure you’re cleaning it with a safe product that you would put in your body.

Remember this is the water you are going to do the following with:

  • Clean dishes
  • Shower
  • Wash your hands
  • Cook 
  • Prepare food

Since you are using this water for hygiene and potentially cooking, you need to ensure that you are not using harsh chemicals. The best option for flushing your tankless water heater is white vinegar.

Vinegar is preferred as it is mild and won’t affect your body if it remains in the system after cleaning. It is also inexpensive and widely available for purchase in most grocery stores. 

Read: How To Keep Your Water Heater From Freezing?

Pump and Dump the Solution

Now it’s time to flush out your tankless water heater. Follow any instructions that your device comes with for the best results. You’ll want to pump the vinegar solution through your device and flush it into a bucket. When you are done, reassemble your heater, which should work like new again.  

How Often To Perform Tankless Water Heater Maintenance?

To keep your tankless water heating running efficiently and giving you the best results, you’ll need to perform maintenance at least once a year in most environments. 

You need to do this frequently because debris builds up in the tank, which can decrease performance and cause some problems with your device’s filter further down the road.

Depending on where you live, you may even need to perform it more frequently.

Some factors that may determine how often you need to flush out your water heater or change the filters include:

  • Water quality
  • Frequency of use
  • How many rooms the unit supplies

Flushing out your water heater is very important, especially if you are running hard water through the tankless water heater. Hard water can quickly result in a buildup of minerals and limescale. 

This video from Matt Risinger explains why it’s so critical to do this:

However, it’s best to check the manufacturer’s guidelines to know when and how to flush your system. 

Final Thoughts

Now that you’ve read some helpful tips on maintaining your tankless water heater, you know important signs to look for and what to do if your system needs to be cleaned.

Follow these tips, and you’ll keep your device in top shape to use for many years to come:

  1. Check all the filters and clean or replace them as needed.
  2. Take proper steps to prepare before starting your work.
  3. Flush the unit annually and only use food-safe products like vinegar.