The Home Depot>Know-How Centre>Buying Guides>Tankless Water Heaters

Buying Guides

Browse by Category

Browse by Space

Related Resources

Products

Projects

Buying Guides

Tankless Water Heaters

Tankless Water Heaters

Point-of-use tankless water heater under bathroom sink

A WATER HEATER THAT’S RIGHT FOR YOU

There comes a time when we say goodbye to our old water heater. With foresight we can replace it with a new model that saves energy and money, and sometimes even space.

The water heating industry in North America has changed greatly. Where we used to be faced only with the decision of what size tank to buy, we now consider energy efficiency and technology. That’s where tankless, often called “on-demand,” water heaters come in.

A huge technological achievement, these innovative systems show significant energy savings over tank-type water heaters (which also means they save you money). Their much-smaller size saves valuable living space as well.

There are two major categories of tankless water heaters: whole house and point-of-use.

Whole house tankless water heater unit
A whole house unit would be installed in a central location and completely replaces a standard tank water heater.

Point-of-use tankless water heater unit
A point-of-use unit provides hot water for a single fixture. Typically, this would be a sink located far from a central hot water source. Because of its very small size, a point-of-use unit is usually located right under the sink.

SHOP ALL TANKLESS WATER HEATERS

AT-A GLANCE BENEFITS:
  • Enjoy huge savings on your energy bills - in some cases you could save up to 50%!
  • Endless supply of instant hot water.
  • No storage tank saves valuable space.
  • Lifespan up to twice as long as conventional tank water heaters.

HOW THEY WORK

Tankless water heaters provide an endless supply of hot water for as long as it’s needed. Because these systems provide hot water on demand, they don’t require a storage tank to store hot water. No storage or holding tank means that tankless water heaters have a life span twice as long as traditional systems because the risk of rust and corrosion is significantly lower.

Gas-powered tankless water heater
Gas-Powered Tankless Water Heaters Gas-powered systems are fuelled by propane or natural gas and heat the water with a burner. A tankless gas water heater needs a gas line to the water heater, and the unit must be vented to the outside. If tankless gas is replacing a gas tank-type water heater, typically it requires a larger gas line. Venting may also need to be upgraded. The right size unit can provide endless hot water for up to two major applications at a time. This unit is a great replacement for a tank water heater.
Electric tankless water heater
Electric Tankless Water Heaters
Tankless electric water heaters heat the water with an electrical element and are also a great replacement for a tank model. A tankless electric water heater needs to be hardwired to the circuit breaker/electrical panel. The size of the existing electrical service to the home needs to be considered as larger units may require an upgrade. Tankless electric water heaters do not need to be vented. Although tankless electric water heaters may output fewer GPM than a tankless gas unit, the larger electric units can provide endless hot water for up to two major applications, which is sufficient capacity for most homes. They are less expensive to purchase than gas tankless, and their smaller size and lack of venting may allow them to be installed where gas tankless units cannot go.
DID YOU KNOW?

Gallons Per Minute (GPM) represents the amount of hot water a tankless water heater provides per minute. Warm incoming water allows a unit to output a higher GPM than cold incoming water. Determining the total GPM of all fixtures that would run at the same time is helpful when sizing a tankless water heater for your home.

INSTALLATION SERVICES

Installation services for water heaters

Contact an Installation Services Expert about having a tankless water heater installed in your home. Consider these questions before your free in-home consultation:

  1. Do you want to power your new water heater by the same source as the old heater (e.g. gas or electric)?
  2. If you are considering a gas unit, does your home already have a gas line and if so, what size is it?
  3. Ideally, where would you like to install your tankless water heater?
LEARN MORE

WATER HEATER COMPARISON CHART

Fuel
Source		 Installation Requirements Horizontal/ Vertical Venting # of Simultaneous Applications
Gas Tank Water Heater Natural Gas or Propane Direct connection to a gas line Either Multiple applications (until hot water in tank is exhausted)
Electric Tank Water Heater Electricity Hardwired to circuit breaker/electrical panel None required Multiple applications (until hot water in tank is exhausted)
Tankless Gas Water Heater Natural Gas or Propane Direct connection to a high-capacity gas line Either Up to two major applications simultaneously
Tankless Electric Water Heater Electricity Hardwired to circuit breaker/electrical panel None required Up to two major applications simultaneously
Write a Review
QUICK RATE:

You have rated

 out of 5 stars.

Do you want to submit this quick rating?

Yes No

Thank you!
Your quick rate has been submitted.

Please note it may take up to 8 hours for your quick rating to appear.

Sorry we are currently experiencing technical difficulties. Please try and resubmit your Quick Rating.

Thank you, you have already quick rated this product.  out of 5