The Difference

In most homes, residential water heaters are equipped with insulated tanks that come in varying capacities, including 40-gallons, 50-gallons, 66-gallons, 75-gallons, 80-gallons, and 120-gallons. Typically, a 40- to 50-gallon tank suffices for a household of 2 to 3 people, with an additional 10 gallons recommended for each extra person in your home. These storage tank water heaters are primarily powered by gas, although some use oil or electricity.

The primary distinction between traditional tank water heaters and tankless water heaters lies in the tank itself. A tank water heater stores hot water within an insulated storage tank, typically a cylinder, whereas a tankless model heats water on demand.

Advantages of Tankless

Tankless water heaters have gained popularity in recent years as homeowners seek ways to reduce energy expenses. The advantages of tankless water heaters over standard models include:

  1. Endless Hot Water: Tankless heaters provide an uninterrupted supply of hot water as they heat water on demand. This contrasts with traditional storage tank water heaters that preheat and store a large tank of water, even when it’s not needed.
  2. Savings on Gas Bills: Tankless water heaters only consume energy (gas, oil, or electricity) when hot water is required, resulting in potential savings on energy bills. According to, switching to a tankless water heater can save you up to 34% on your water heating costs.
  3. Space Efficiency: Tankless water heaters are significantly smaller than traditional storage tank models. This means more space in your home, as tankless units can be wall-mounted or even installed outdoors.
  4. Extended Lifespan: Tankless water heaters typically have a longer lifespan of about 20 years, compared to the 10–15 years expected from traditional storage tank water heaters.

Disadvantages of Tankless

However, tankless water heaters also come with certain drawbacks, including:

  1. Higher Installation Costs: The average cost of installing a tankless water heater is around
    $2800, considerably more than the $800 to $1500 range for a water heater with a storage tank.
  2. Inconsistent Water Temperatures: Tankless heaters may deliver inconsistent water temperatures since they heat water on demand. In situations where there is a high demand for hot water, such as running a dishwasher or washing machine while taking a shower, the water temperature can drop significantly.
  3. Delayed Hot Water Delivery: Tankless water heaters take longer to deliver hot water as they need time to heat up the incoming cold water. The flow rate can also affect delivery time.

In summary, tankless water heaters offer several advantages over traditional storage-tank water heaters, including a continuous supply of hot water, enhanced energy efficiency, space-saving designs, and extended lifespans. However, they also have drawbacks, such as higher installation costs, inconsistent water temperatures during peak demand, and potentially longer wait times for hot water delivery.

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