Pros And Cons Of On-Demand, Tankless Water Heaters



When it’s time to start looking for water heater replacement options, you may be considering switching to a tankless, or on-demand, water heating system. While tankless water heaters take up less space and can save you a lot of energy, there are some things to keep in mind, such as higher upfront costs and the possibility that they won’t produce enough hot water for your household.

Here’s what you need to know before making the switch to tankless water heating.

Tankless Water Heater Pros

Energy Savings

The number one advantage of a tankless water heater is improved energy savings. Tankless water heaters use about 30-50% less energy than traditional tank units since they only heat water when you need it. That’s why tankless water heaters are sometimes called “on-demand” units.

Using about half as much energy as a traditional water heater (mostly due to avoiding standby heat loss), the typical family can expect to save about $100 or more on energy costs every year.

If you go for a gas-fired tankless unit as opposed to an electric one, consider models that have an intermittent ignition device (IDD) rather than a standing pilot light.

Continuous Flow of Hot Water

Since tankless units heat the water as it flows through the unit, you won’t have to wait for water to get hot in a storage tank. The continuous flow of hot water is great for supplying water to a big hot tub or whirlpool.

Keep in mind that tankless units may not be able to supply enough hot water if there are simultaneous demands. For instance, if you are filling a bath with hot water while simultaneously running the dish washer, there may not be enough hot water for both uses.

For larger households, you may need a larger more expensive unit, or two or more tankless water heaters, connected in parallel. There can even be a separate tankless water heater for appliances, such as dish washers and clothes washers.

Small Size

Tankless units don’t have to hold water in a tank, they are a lot smaller and more compact. The smaller tankless units take up very little space and can be mounted on a wall.

Longer Lifespan

In contrast to traditional tank units, which have a lifespan of around 10-15 years, most tankless units last more than 20 years. Keep in mind that tankless units, just like traditional units, require proper annual maintenance.

Reduced Risk of Water Damage

Water heater tanks can leak and burst, which can damage property and cause thousands of dollars’ worth of water damage. While tankless water heaters can also leak, they won’t be flooding your home with 40-60 gallons of water like a traditional water heater can.

Tankless Water Heater Cons

Upfront Cost

The biggest disadvantage of tankless water heaters is the initial cost. While tankless water heaters last longer and have lower operating costs that usually offset the higher purchase price, the upfront costs are significant.

One reason why the upfront costs are so high is because tankless units require a special, dedicated sealed vent system.

Not Enough Hot Water for Larger Households

Tankless water heaters produce a continuous flow of hot water, but they often can’t produce enough hot water for multiple uses. This can be a problem if you want to take a shower while running the dishwasher at the same time.

You can install a larger unit or multiple units, but this can get expensive.

Learn more about tank versus tankless water heater options.

If you want to know more about the pros and cons of tankless water heaters, contact the team at Service Champions. We provide professional tank and tankless water heater installations with a single, upfront price.

Cover image by Behrat [CC BY-SA 3.0 or GFDL], from Wikimedia Commons

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