If you’re a homeowner in Ottawa, you’ve likely heard the buzz around tankless water heaters. They’re compact, energy-efficient, and provide hot water on demand—but what’s actually going on behind the scenes? In this guide, we’ll focus on the inner workings of a tankless hot water heater, explain the core differences between electric and gas models, and help you understand what size might be right for your home.
What Is a Tankless Hot Water Heater?
A tankless hot water heater—also known as an on-demand water heater—doesn’t store hot water like traditional tanks. Instead, it heats water instantly as it passes through the unit. When you turn on a hot water tap, cold water flows through a heat exchanger, which is rapidly warmed by either an electric element or a gas burner. This means no waiting for a storage tank to refill, and virtually endless hot water when you need it.
So, how long does it take to heat the water? Practically speaking—just a few seconds. The heating process begins immediately when you open a tap, and depending on the distance between the heater and the fixture, you’ll typically feel hot water flowing within 5 to 15 seconds. Unlike a traditional tank, which can take 30 minutes or more to recover after the hot water runs out, a tankless unit never “runs out” in the same way. This difference is a key benefit when comparing a tankless water heater vs tank system.
The beauty of this system lies in its efficiency. Because it only heats water as needed, you’re not paying to keep 40 or 50 gallons of water hot all day. That’s why many people ask, “do tankless water heaters save money?” The answer is yes—especially over the long run.
Electric vs Gas Tankless Water Heaters
There are two primary types of tankless heaters: electric and gas. Each functions the same way at its core—by heating water on demand—but uses different energy sources to do so.
Electric Tankless Units
- Use electric heating elements to warm water
- Easier and cheaper to install
- Compact and ideal for smaller homes or point-of-use installations
- Don’t require venting
Gas Tankless Units
- Use a gas burner to heat water
- Higher upfront installation cost
- Require proper venting and gas lines
- Typically deliver higher flow rates, making them more suitable for larger households
Ottawa homeowners often ask: are electric tankless water heaters any good? or are gas tankless water heaters pretty good? The answer depends on your household’s hot water usage and existing energy setup. Both are effective, but your choice will influence installation needs and ongoing operating costs.
What Size Tankless Water Heater Do You Need?
Sizing a tankless water heater is all about your home’s hot water demand. Tankless units are rated by flow rate (in litres per minute or LPM in Canada) rather than storage capacity.
For example:
- A shower may use 6–9 LPM
- A dishwasher can use 4–6 LPM
- A washing machine typically needs 6–8 LPM
If multiple fixtures run at the same time, you’ll need a unit that can handle the combined flow rate. This is especially true for those considering a large tankless hot water heater. In general:
- Small home or condo: 5–7 LPM
- Average home with 2-3 occupants: 7–10 LPM
- Large home with high simultaneous usage: 10+ LPM
Professional sizing ensures you never run out of hot water—especially during Ottawa winters.
The Installation Process
The installation of a tankless hot water heater in Ottawa will vary based on the model and your home’s current setup. Here’s what’s typically involved:
- Electric models: May need upgraded wiring or a new breaker
- Gas models: Require venting and sufficient gas flow
- Mounting: Most are wall-mounted to save space
At Rick Menard Heating & Cooling, we take care of the entire process—from consultation and unit selection to safe, efficient installation. Our technicians are fully certified and familiar with local code requirements in Ottawa.
Final Thoughts: Is a Tankless Hot Water Heater Right for You?
If you’re asking, “how does a tankless hot water heater work?”—you now know it’s all about on-demand heating with no storage tank required. Whether you choose electric or gas, these systems are compact, efficient, and provide a consistent stream of hot water.
In addition to being practical, tankless systems help address other common questions like:
- Are tankless hot water heaters worth it?
Yes, for many households they are. Tankless systems offer long-term energy savings, longer lifespans, and endless hot water, making them a smart investment—especially if you plan to stay in your home for years. - Is an electric tankless water heater worth it?
Yes, for smaller homes or point-of-use needs. Electric models are energy-efficient, low-maintenance, and easier to install. However, they may struggle with high simultaneous demand in larger households.
- Are tankless water heaters good for Ottawa winters?
Yes, when properly sized and installed. Modern tankless units are designed to handle cold Canadian groundwater temperatures, though gas models tend to perform better than electric in high-demand, cold-weather situations.
If space savings, energy efficiency, and modern convenience matter to you, upgrading from a traditional tank system is a smart move. Still wondering about tankless heater vs tank options? We’re happy to walk you through the pros and cons specific to your household.
Reach out to Rick Menard Heating & Cooling for expert advice and professional service. We’ll help you choose the right system—and make sure it’s installed right the first time.
