Tankless Water Heater Pros and Cons

In this guide we will cover the Tankless Water Heater Pros and Cons. We hope to give you a better understanding, whether to choose a tankless water heater or not. There are a lot of good reasons to purchase an on-demand water heater as they’re also referred to as.

Tankless Water Heater Pros and Cons
Now let’s get to the pros and cons of tankless water heaters.

Pros of tankless water heaters

1. Space savings

– the first thing you will notice about tankless water heaters are their small size compared to standard water heaters. They are wall mounted either indoors or outdoors. Having such a small design footprint frees up a lot of space that can be used for something else like storage.

When an outdoor mounted tankless water heater is used, you all that space back previously used by a tank water heater. They can also be mounted in closets and crawlspaces as well.

2. Endless hot water

– the water won’t be instant as there’s no tank storing hot water. Once it starts heating and gets to the facet or showerhead, it will be consistent. There is no tank to run out of hot water, so two people can take showers at the same time. Or be washing clothes while someone is showering, without having to hurry to get out before it gets cold.

3. Lifespan

– the life span of standard tank water heaters is about 8-10 years. Whereas tankless water heaters can last twice as long, depending on water quality and maintenance. So you get the space saving advantage and have to replace the water heater less often. This can really make the cost differences more equal. Warranties are typically much longer on these as well.

4. Energy and Money savings

– another pro of tankless water heaters is the savings of both energy and money you’ll save month-to-month. Tankless water heaters are so much more energy efficient and only heat water when necessary. No more spending money constantly heating 40+ gallons of water all day, everyday for no reason. This is one of the great advantages of on-demand water heaters and how they got this name.

5. Risk of Water Damage

– when a traditional tank water heater leaks or bursts you can come home to find a flood floor. That can ruin floors, cause mold issues and cost thousands of dollars in damages. Tankless water heaters can leak but they won’t flood your home like a tank water heater can.

Cons of Tankless Water Heaters

1. Costs

– switching to and installing a tankless water heaters can be quite a bit more expensive that replacing your standard tank water heater. This is because sometimes the water heater location must be relocated entirely. Costing money to relocate gas and water lines. Plus the exhaust vent will be schedule 40 PVC or stainless steel, which will be different from the typical vent.

Normally though these costs are made up over time in the higher efficiency, using less energy and water savings. Not to mention tankless water heaters normally last about twice as long as a tank water heater.

2. Hot Water Supply

– one of the drawbacks of tankless water heaters are they can be limited in how much water they can provide. Most models are perfect for your average 2-3 bathroom home in southern climates. In colder northern climates they are not as efficient.

You will find a lot of models are compatible with the standard 1/2″ residential gas line. For the larger on-demand water heaters with high BTU’s, they require 3/4″ gas line. This can be an issue, especially in terms of costs to upgrade gas lines. This is why tankless water heaters can become limited to the amount of hot water they can provide with high demand.

3. Maintenance

– another drawback of tankless water heaters is the maintenance. They can require much more than typical water heaters. Depending on your water quality the system may need to be flushed or descaled of minerals, etc. This can also increase the costs of owning one of these.


There you have it, pros and cons of tankless water heaters. As these types of water heaters are getting more popular, it can be a great choice. We hope this guide has helped you learn more about on-demand water heaters if you so choose to buy one. Be sure to view our tankless water heater reviews of the top rated ones on the market.

Jack Larry

My name is Jack Larry and I am a perfectionist and write this blog and a few more for perfectionists like me. Cooking is my craze and temperature maintenance is the tip to cook a perfect meal. So my gadget experience and cooking skill qualifies me to be your Thermometer Guru!

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