What is The Downside of a Tankless Water Heater?

Last Updated On June 11, 2024

Updated on February 15, 2023



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The Downside of a Tankless Water Heater

The biggest downside of a tankless water heater is the upfront cost; this includes the purchase price of the new tankless unit plus installation costs. 

You can eventually recoup your money back in either gas or electric utility bill savings, but you need to plan for the price of the tankless unit and the labor charge for installation. It can get costly if you need a new gas line or one extended. This is why it’s important to calculate the true cost of a tankless water heater and understand your breakeven point before you get started.

What should you plan for? You can expect to pay a couple of thousand dollars to replace a standard tank-style hot water heater with a new energy-efficient tankless unit. Most people have no issues with the initial price tag because of all the advantages tankless water heaters provide. 

Even with all the pros of owning a tankless water heater, there is also a list of cons…

Read on as we tell you the “not so talked about” downsides to tankless water heaters.

What's In This Guide?

      6 Main Disadvantages of a Tankless Water Heater System

      Ok, for all their benefits there are some reasons you might not want to invest in a tankless unit. Here are the top 6 things to be aware of.

      1. Cost of New Tankless Unit

      You don’t always have to buy the most expensive hot water heater on the market. Some tankless water heater brands like Rheem and Rinnai can be purchased for under $800.

      Noritz is another high-end brand with a very popular tankless unit that runs on either natural gas or propane. These hybrid units start at around $1,300, but most consumers feel they are well worth it.

      2. Upfront Installation Price

      A professional plumber must install tankless water heaters. The average cost for a basic tankless unit retrofit is around $2,000. This cost can increase if any plumbing pipes or gas lines have to be modified or rerouted. An easy “swap” can cost much less if it’s an easy job that is accessible for the plumber.

       3. Lengthy Return on Investment (ROI)

      It can take 10-20 years for a tankless water heater to pay back its initial price tag in utility savings. This varies widely depending on your location and your energy costs. You should always do your research to find which tankless water heater unit would work best for your unique family situation. 

      It also helps to shop around for a professional plumber that won’t charge an arm and a leg for the installation.

      Did you know? You should flush a tankless water heater regularly to help keep it clean and efficient.

      did you know The Downside of a Tankless Water Heater

      4. Inconsistent Temperature (Sometimes)

      Each tankless water heater unit is manufactured with a specific flow rate capacity. The flow rate depends on the amount of water that is required for each plumbing fixture and appliance in our home. 

      A whole-house tankless water heater can heat the entire house from a single source. The water temperature can become inconsistent when multiple people are showering at the same time in different bathrooms. You can’t ask one unit to do too much for its capacity rating.

      Installing a single-point-of-use system at every shower or appliance is another option that allows you to heat each device independently from one other. This is typically what is done for off-the-grid living.

      The label on each unit will provide the exact sizing and “temperature rise” information necessary for choosing the best tankless water heater for your specific situation.

      5. Power Outage Problems

      A tankless water heater is a very technical piece of machinery. Like most modern technology, a tankless unit has an internal control panel that works as a brain “so to speak.” This brain runs off of electricity. When our power goes out so does our hot water.

      6. Increased Maintenance

      Calcium and lime debris can build up quickly on a tankless water heater due to so much going on in such a small space, especially if you have hard water.

      Neglecting the maintenance of a tankless water heater can severely reduce potential savings in our tankless system. You will need to flush the system annually for any hard water build-up, or it can reduce its lifespan. Installing a water softener can help with this issue as well. 

      Here is a great video explaining the benefits and disadvantages of owning a tankless water heater versus a tank-style heater.

      Final Thoughts on the Downsides of a Tankless Water Heater

      The good outweighs the bad when it comes to the pros and cons of tankless water heaters. The money you save, along with the energy efficiency of a tankless water heater will almost always outshine the initial cost of installation. 

      Maintenance on a tankless water heater can be a bit more complex but doesn’t require much more labor than a tank-style water heater. 

      You even have the option to install individual heating units at every plumbing fixture if necessary. There are some downsides to a tankless water heater, however, tankless systems are getting more efficient each year as technology advances.

      FAQs on Tankless Water Heater Downsides

      What is the main downside of a tankless water heater? 

      The biggest issue with a tankless water heater is the expensive cost of the installation. It can be many years before you see a return on investment in your utility bills.

      Is a tankless water heater worth it?

      The Energy Efficiency of a tankless water heater makes the unit worth it. You will eventually make your money back in savings for the high cost of installation. The tankless water heater doesn’t have the same problems a tank-style water heater does.

      How do I save money with a tankless water heater? 

      It’s no secret that you will pay a lot upfront for a tankless water heater. You will immediately see a drastic reduction in your utility bills. These savings will eventually add up and make the tankless water heater worth it.

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      About Plumbing Navigator

      We write about "all things plumbing," helping you navigate common questions, repairs, and the best plumbing products on the market.

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      We write about “all things plumbing,” helping you navigate common questions, repairs, and the best plumbing products on the market.

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