How To Choose The Best Tankless Water Heater In Ontario? Our 2023 Buyer’s Guide

How To Choose The Best Tankless Water Heater In Ontario? Our 2021 Buyer’s Guide

You’re interested in buying or renting a tankless water heater, but you’re taking the time to look around. You want to make sure you’ll get the most out of your purchase. Fair enough. Most homeowners who buy tankless water heaters in Scarborough do so because they want more — more energy efficiency, more savings on electricity, and a more reliable source of hot water.

Tankless water heaters have revolutionized the way we experience hot water in our homes. Their energy efficiency, space-saving design, and endless supply of hot water make them an appealing choice for homeowners in Ontario. However, with numerous brands, models, and technologies available, selecting the right tankless water heater can be a daunting task. This comprehensive buyer’s guide will equip you with the knowledge needed to make an informed decision for your Ontario home.

Be an informed consumer and get more from your new appliance. Read our guide to help you select the best tankless water heater in Ontario:

  1. What Are Some Trusted Tankless Water Heater Brands?
  2. How Does A Tankless Water Heater Work?
  3. Why Install A Tankless Water Heater?
  4. How Long Do Tankless Heaters Last?
  5. Gas Vs. Electric Tankless Water Heaters
  6. Condensing Vs. Non-Condensing Tankless Water Heaters
  7. What Is The Flow Rate Of A Tankless Unit?
  8. Do I Need To Worry About Sizing?

What Are Some Trusted Tankless Water Heater Brands?

Selecting the best tankless water heaters from all the options out there is essential for ensuring reliability, efficiency, and longevity. Let’s delve deeper into some of the most trusted tankless water heater brands available in Ontario. We recommend 3 manufacturers: Navien, Rinnai, and Noritz. These are the best tankless water heater brands around due to their reliability, efficiency, and quality. All three are available for purchase and installation through Dr HVAC.

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Navien Tankless Water Heater

Navien is a leading name in the tankless water heater industry, known for its cutting-edge technology and energy-efficient solutions. Their NPE-A Series, including models like the 180A, 210A, and 240A, are highly regarded for their performance and durability. Navien tankless water heaters offer a seamless supply of hot water, ensuring comfort and convenience in your home.

Rinnai Tankless Water Heater

Rinnai is a trusted brand with a legacy of producing high-quality tankless water heaters. The RUR199iN model, in particular, stands out for its exceptional efficiency and advanced features. Rinnai tankless water heaters are designed to deliver a consistent flow of hot water while minimizing energy consumption.

Noritz Tankless Water Heaters

Noritz is recognized for its innovative tankless water heaters, and the EZ111 model is no exception. Offering a blend of performance, efficiency, and reliability, Noritz tankless water heaters are engineered to meet the hot water demands of modern households. With Noritz, you can expect a continuous supply of hot water without compromising on energy savings.

How Does A Tankless Water Heater Work?

Tankless water heaters operate on-demand, heating water only when it is needed. When a hot water tap is turned on, cold water flows through a heat exchanger, where it is rapidly heated by a gas burner or electric element. This process ensures a continuous and instantaneous supply of hot water, eliminating the need for a storage tank.

A tankless water heater looks very different from the traditional hot water tank we’re all used to. Instead of a large cylindrical tank, you’ll see a compact box, usually mounted on the wall, with a network of pipes and valves attached. Here’s a quick look at how a tankless heater works:

  1. Turning on a fixture (shower or hot water faucet) activates water flow into the heater.
  2. This activates the flow sensor, which in turn triggers the control panel.
  3. The control panel switches on the fan.
  4. The fan has several essential functions: drawing in air from outside, opening the gas valve, and igniting the gas burner.
  5. Exhaust gases from the combustion are vented outdoors, through either an exterior wall or the roof.
  6. The gas burner produces heat, which the heat exchanger transfers to the incoming water.
  7. The mixing valve tempers the water — which is now superheated — to avoid scalding.
  8. The water is piped to your shower or faucet.
  9. You enjoy a continuous flow of hot water for as long as you like.
  10. When the fixture is turned off, the flow of hot water ends and the gas burner shuts down.

Why Install A Tankless Water Heater?

Glad you asked! There are tons of benefits to installing a tankless water heater.

Energy Efficient

The best tankless water heaters are highly energy efficient because they only heat water as it is needed. This eliminates the standby energy losses associated with traditional storage tank water heaters, resulting in lower utility bills.

Energy efficiency is what frequently motivates people to switch to a natural gas or electric tankless water heater. Conventional tank water heaters are one of the highest residential energy sources, second only to heating and cooling systems. That’s because they waste an awful lot of energy keeping a huge tankful of water hot 24/7, whether it’s needed or not.

Tankless water heaters, by contrast, heat only as much water as you need when you need it. They do not store hot water for future use. The happy result? Throughout its lifetime, a tankless water heater can save you thousands of dollars on your natural gas or electricity bills.

A great choice for energy savings: Water heaters that have earned certification by the Energy Star energy-efficient appliance program.

More Hot Water

​​Imagine never again being stuck with a cold shower because your kids have used up all the hot water! That’s what you can expect when you switch to a tankless water heater. Aptly described as providing “hot water on demand,” this appliance will continue heating water as long as you need it.

With a tankless water heater, you’ll never run out of hot water. Unlike storage tank heaters, which have a limited supply, tankless units provide a continuous flow of hot water for as long as you need it.

Saves Space

Tankless water heaters are compact and wall-mounted, saving valuable floor space. They can be installed in smaller utility closets, under sinks, or even outdoors, making them an ideal choice for homes with limited space.

Approximately the size of a suitcase, tankless water heaters have a trim profile and fit easily into a small space such as a closet, as long as they’re properly vented. This frees up floor space — especially important when you live in a small house, a townhome, or a condo.

Longer Life Span

Tankless water heaters have a longer lifespan compared to traditional storage tank heaters. With proper maintenance, they can provide reliable hot water for two decades or more.

Tankless water heaters last longer since they don’t experience all the wear and tear that results from storing a large volume of heated water. Typically, the life span of a tankless water heater will be 20 years or more, compared to an average of 8-12 years for a hot water tank.

Less Chance of Flooding

Since tankless water heaters do not have a storage tank, there is no risk of catastrophic tank failure and subsequent flooding. This reduces the potential for water damage to your home. Your risk of catastrophic water heater flooding and water damage to your basement is greatly reduced when you opt for a tankless water heater. Tankless heaters don’t store large quantities of water (hot water tanks hold about 150-300 litres!). So even if they develop a water heater leak — usually when they reach an advanced age and are due for replacement — it will be a much smaller volume. Adding a drain pan to your tankless water heater installation will fully contain any future leakage.

How Long Do Tankless Heaters Last?

The best tankless water heaters are known for their durability and longevity. On average, a well-maintained tankless unit can last up to 20 years or more. Regular maintenance, such as flushing the system and checking for mineral buildup, can significantly extend the lifespan of your tankless water heater.

Tankless water heaters are renowned for their durability and longevity, making them a reliable and cost-effective choice for homeowners. On average, a well-maintained tankless water heater can last up to 20 years or more. This lifespan is considerably longer compared to conventional water heaters, which typically have a lifespan of around 10-15 years.

Gas Vs. Electric Tankless Water Heaters

Natural Gas Tankless Water Heater


  • High flow rates for multiple applications.
  • Energy-efficient and cost-effective in regions with natural gas availability.
  • Ideal for larger households with higher hot water demands.


  • Higher upfront cost and installation complexity compared to electric models.
  • Requires proper venting for exhaust gases.

Electric Tankless Water Heaters


  • Simplified installation and lower upfront cost.
  • Suitable for smaller households or areas without natural gas access.
  • Highly efficient in regions with lower electricity rates.


  • Limited flow rates, which may be insufficient for simultaneous hot water usage in larger households.
  • May require electrical upgrades to support higher amperage.

Consider your household size, hot water demand, and available energy sources when choosing between gas and electric tankless water heaters.

Condensing Vs. Non-Condensing Tankless Water Heaters

Condensing Tankless Water Heaters


  • Higher energy efficiency, with an efficiency rating of over 90%.
  • Extract additional heat from exhaust gases for more efficient operation.
  • Lower greenhouse gas emissions.


  • Higher upfront cost compared to non-condensing models.

Non-Condensing Tankless Water Heaters


  • Lower upfront cost compared to condensing models.
  • Still highly efficient compared to traditional storage tank water heaters.


  • Slightly lower energy efficiency compared to condensing models.

Condensing tankless water heaters are the more energy-efficient option, making them a greener choice for eco-conscious homeowners. However, they come with a higher initial investment.

What Is The Flow Rate Of A Tankless Unit?

The flow rate of a tankless water heater refers to the amount of hot water it can deliver per minute. It is measured in gallons per minute (GPM). When choosing an electric or gas tankless water heater, consider the number of fixtures and appliances that will be using hot water simultaneously. This will help determine the appropriate flow rate for your household’s needs.

The flow rate of a tankless water heater is a crucial factor to consider when choosing the right unit for your home. It refers to the amount of hot water the heater can deliver per minute, measured in gallons per minute (GPM). Understanding the flow rate is essential to ensure that the tankless water heater can meet the hot water demands of your household.

When researching the best tankless water heaters, it’s important to calculate the peak demand in your home. Consider how many fixtures and appliances may be in use at the same time to determine the appropriate flow rate. This ensures that you have a consistent and reliable supply of hot water, even during periods of high demand.

Do I Need To Worry About Sizing?

Yes, proper sizing is crucial when selecting a tankless water heater. It ensures that the unit can meet the hot water demands of your household. Factors to consider include:

Peak Demand: Calculate the maximum number of hot water fixtures and appliances that may be used simultaneously.

Temperature Rise: Determine the temperature rise needed to achieve the desired hot water temperature in your region.

Flow Rate: Ensure the tankless water heater can provide the necessary flow rate for your household’s demands.

Consult a Dr HVAC technician or use sizing calculators provided by manufacturers to accurately determine the right size for your tankless water heater.

Choose The Best With Dr HVAC

Selecting the best tankless water heater for your Ontario home is a significant decision, and the experts at Dr HVAC are here to help. With a range of trusted brands and a team of experienced technicians, we provide top-notch installation services to ensure your home has a reliable supply of hot water. Contact us today for personalized recommendations and professional installation of your tankless water heater.