Tankless vs Tank Water Heaters: Which One Is Better for Your Home?

How Tank and Tankless Water Heaters Work

A traditional water tank heater stores hot water inside an insulated tank, keeping it ready for use whenever needed. Cold water enters the tank through a supply line and is heated by either a gas burner or electric heating elements. As the water warms, it naturally rises to the top, ready to go to sinks, showers, or appliances whenever you need. Thanks to this design, you have a reserve of hot water, but once it’s used up, the tank needs time to heat a new supply.

A tankless hot water heater heats water only when it’s needed. Instead of storing hot water, it uses a high-powered heat exchanger to quickly warm the cold water as it passes through the unit. This on-demand system means you won’t run out of hot water, and the heated water is delivered directly to you when you need it at the set temperature almost instantly.

Tankless vs Tank Water Heater: Key Differences

Choosing the right water heater for your home starts with understanding how each type works, and what they can offer. Both tank and tankless hot water heater models provide hot water, but they do so in different ways. Each system heats water differently, and knowing how they work can help you decide which one fits your needs best. 

Installation and Space Requirements

A tankless water heater installation takes up very little room and can be mounted on a wall, making it a good choice for places where space is tight. Water tank heaters are much larger and need a dedicated spot in a basement, garage, or utility room. The amount of space you have available is an important consideration in deciding which type of water heater will work best for your home.

Energy Efficiency and Operating Costs

A tankless water heater heats water only when needed, which reduces wasted energy and can help lower utility bills. Many models are highly efficient, sometimes reaching close to 98%. A water heater tank keeps water hot all the time, which can waste energy and usually results in lower efficiency, usually between 65-92%. Tankless units also usually cost more upfront, while their lower reliability might call for more frequent repairs. Tank water heater units cost less to buy but may cost more in the long run because of higher energy use and shorter service life. Unlike tankless models, tank heaters can keep up with demand and don’t require extensive upgrades to operate. 

Performance and Hot Water Supply

Tank water heater units can only deliver the amount of hot water stored in the tank. Once it’s used up, you’ll need to wait for more to heat. This can be inconvenient when many people need hot water in a short time. Tankless models heat water on demand, so you don’t run out, even if you’re running the dishwasher, filling the tub, and taking showers back-to-back. Tankless models are a better fit for households with higher or unpredictable hot water needs.

Lifespan and Durability

Hot water heater tank models usually last about 8-12 years. With proper maintenance, tankless models may run for 15 years and more. The longer life of tankless units comes from not storing large amounts of water. So there’s less risk of things like rust, leaks, and corrosion. They also face less wear since they only heat water when needed, instead of cycling on and off all day. Hot water heaters tanks are more prone to damage from constant heating and holding water, and when they fail, they can sometimes cause leaks or flooding. 

Maintenance Needs

A tankless water heater needs regular upkeep to keep it running smoothly, especially in areas with hard water. This usually means descaling to get rid of mineral buildup and having a plumber do yearly inspections. The heater water tank also needs maintenance. Mostly it means regularly flushing the tank to clear out sediment. Both tank hot water heater and tankless can greatly benefit from professional servicing since both models can get less leaks, better performance, and extend their lifespan. Consistent care is important for keeping either type working well.

Tankless Water Heater vs Tank: Pros and Cons

A water heater with a tank has a lower upfront price and is easier and cheaper to repair. They can heat a large amount of water at once, so they’re good for running multiple appliances simultaneously. But they can use more energy, take longer to heat water, have a limited hot water supply and shorter lifespan, and require more space for installation.

Tankless water heaters are compact, provide endless hot water, potentially lower monthly energy costs, and may last longer with proper care. However, they cost more to buy, may require multiple units for large households, and repairs can be pricier and more frequent.

Electric vs Gas Water Heaters: Which Option Is Better?

Electric water heater installation is generally easier, requires less maintenance, and doesn’t need a gas line or venting. They usually have a lower upfront cost for installation and are perfect for homes where gas connections aren’t available. But they can be more expensive to run over time if electricity rates are high, and they also heat water more slowly than gas models.

Gas water heaters heat water faster and can be more economical if natural gas is cheaper than electricity in your area. They’re ideal for larger households with high hot water demands. The trade-off is a higher installation cost, and the need for proper venting.

Electric Tankless Water Heater vs Tank Water Heater

Electric tankless water heaters heat water only when needed, but in real-world use, they often fall short. They struggle to keep up when multiple fixtures run at the same time, require a lot of electricity, and may leave you with inconsistent hot water during peak demand. For these reasons, they’re generally not a good choice for most homes.

A traditional electric hot water tank heater stores a full supply of hot water, ready when you need it. They use more energy to maintain temperature, but they’re easier to install, reliable, and can serve several fixtures at once without sudden temperature drops.

Electric vs Gas Tankless Water Heaters

Electric tankless water heaters often seem like a good choice because of their smaller size and lack of venting needs, but in practice, they have very serious drawbacks. They require very high electrical current, often beyond what many homes can support without costly upgrades, and they struggle to meet the GPM needs of an average household. This makes them highly unreliable for consistent hot water.

Gas tankless water heaters heat water faster, making them better for larger homes. They work during power outages if equipped with a battery-backup ignition, but the installation costs are usually higher. While their installation cost is higher, they’re the more dependable choice.

Conclusion

Choosing between tankless vs tank water heater, or electric and gas models, depends on a few things, like your home’s hot water needs, available space, and budget. Tankless units offer endless hot water and may last longer. Traditional tanks have lower upfront costs and simpler repairs. Electric models are easier to install in many homes, while gas water heater installation provides faster heating and higher capacity if your home has gas lines available. 

Are you planning an electric water heater replacement or a gas water heater replacement? Working with an experienced hot water heater plumber will help you find the right system.