By Demand: Tankless Water Heaters

A conventional storage water heater taps the average household for up to $450 in energy costs per year, and some of that energy is wasted. Storage units use energy to maintain tank temperature, even when no hot water is being drawn. Tankless, or demand water heaters, eliminate those standby losses, saving energy and money.

How they work

Tankless water heaters are used for whole-house water heating, as well as remote bathrooms or hot tubs. They can also provide hot water for home heating systems.

Unlike conventional storage water heaters, tankless units only heat water as it's used — on demand. When a hot water tap is turned on, cold water is drawn into the unit, and a sensor activates the internal heat exchanger. As the water flows through, it's heated. The unit delivers a constant supply of hot water, but the flow rate is limited by the output of the heat exchanger.

Benefits of going tankless

Tankless water heaters offer a number of advantages over conventional storage units, including:

  • Elimination of standby losses
  • Continuous hot water
  • Low maintenance costs
  • Small size frees up space in basement or utility room
  • Average service life of 20 years more (compared to 10 to 12 years for storage units)

Tankless water heaters may cost more to purchase, but can pay for themselves through energy savings.

Finding the right water heater

Tankless models are rated by how many gallons of hot water they produce per minute (GPM) at a given temperature rise (minimum 60°F). Gas-fired condensing tankless water heaters cost more but provide even greater energy savings.

To size a tankless water heater, you'll need to determine your hot water demand. An experienced plumber can provide an accurate estimate, but here are some average figures:

  • Shower: 2.5 GPM
  • Clothes washer: 3.3 GPM
  • Dishwasher: 1.3 GPM

Consult with your supplier about correctly sizing a tankless unit.

Get up to $1,200 in rebates from Pensacola Energy.

Pensacola Energy offers up to $1,200 in rebates when you switch to natural gas tankless water heating. To learn more, visit pensacolaenergy.com or call 850-436-5050.