Tank vs Tankless Water Heaters for Your Pickering Home
By Pickering Plumbing Team · Published · Updated
How each type works
A traditional tank water heater stores a set amount of water and keeps it hot around the clock, using gas or electricity. When you turn on a hot tap, hot water flows out of the top of the tank and cold water flows in at the bottom to be heated. Once the stored hot water is used up, you wait for the tank to recover.
A tankless water heater, sometimes called on-demand, doesn't store water. When you open a hot tap, water flows through a heat exchanger that heats it as it passes. As long as the unit can keep up with the flow, you get hot water without running out.
Both work well when they're sized and installed properly. The right choice depends on how your household uses hot water, the space you have, and what your home is set up for.
Hot water supply: running out vs keeping up
With a tank, the limit is volume. Back-to-back showers, a bath and a load of laundry can drain it, and then you wait. A bigger tank helps but takes more space and keeps more water hot all the time.
With tankless, the limit is flow rate. It won't run out, but there's a maximum amount of hot water it can produce at once. If several showers, the dishwasher and the washing machine are all running together, an undersized unit may not keep up, and the water can turn lukewarm. Proper sizing based on how many fixtures you use at the same time is the key.
Tankless units can also have a short delay before hot water arrives, and some people notice a brief cold burst between uses. Good installation and the right model minimize this.
Space and installation
Tankless units mount on the wall and are about the size of a small suitcase, which frees up floor space in a utility room. That's a big plus in a finished basement or a tight mechanical room.
Installation is where tankless gets more involved. A gas tankless unit often needs a larger gas supply line, different venting than your old tank, a condensate drain on many models, and an electrical outlet. Switching from a tank to tankless can mean more work than a straight tank-for-tank swap, so the upfront cost is usually higher.
Replacing a tank with a similar tank is the simplest job. The connections, venting and gas line are usually already in place.
Running costs and lifespan
Because a tank keeps water hot even when no one is using it, it loses some energy all day long. A tankless unit only heats water when you need it, so it can use less energy, especially in households that use hot water in short bursts. How much you save depends on your usage and utility rates, so be wary of anyone promising a specific number.
Tankless units generally have a longer service life than tanks when they're maintained, and many of their parts can be replaced. A tank, by contrast, is usually replaced as a whole once it starts to leak.
Hard water and maintenance
Many homes in Durham Region have hard water, which carries minerals that build up as scale when water is heated. Both types are affected.
- In a tank, scale and sediment settle at the bottom. This can cause popping or rumbling sounds, reduce efficiency and shorten the tank's life. Flushing the tank periodically helps.
- In a tankless unit, scale builds up inside the heat exchanger and can trigger error codes or reduce performance. Most manufacturers recommend periodic descaling, and many installers suggest a water softener or scale filter in hard water areas.
Whichever you choose, follow the manufacturer's maintenance schedule. Skipping it is one of the most common reasons water heaters fail early.
Rent, buy or replace?
Many Ontario homes have a rented water heater. If yours is rented and getting old, you can usually choose to keep renting, ask the rental company for a replacement, or buy your own unit. If you go the ownership route, you'll need to arrange the return of the rental unit with your provider and check whether there are any buyout or removal terms in your agreement.
Ask about any rebates or incentive programs that might apply to high-efficiency water heaters. These change over time, so check with your utility, the City of Pickering or the Region of Durham for what's current.
Which one is right for you?
A tank is often a good fit if your current tank is near the end of its life, you want the simplest and lowest-cost replacement, and your household doesn't regularly run out of hot water.
Tankless often makes sense if you run out of hot water, want the floor space back, plan to stay in the home for years, and are comfortable with a higher upfront cost for longer service life.
If your tank is leaking right now, you may not have time to weigh every option. Our water heater repair and installation service can get hot water back quickly and talk you through what to replace it with. If you're planning ahead, our tankless water heaters page explains the installation process in more detail. Homeowners in newer neighbourhoods like Duffin Heights often find their builder-installed tank is the first big appliance to need attention.
Common questions about tank and tankless heaters
How long does a water heater last? A tank typically lasts around 8 to 12 years, and tankless units often last longer when they're maintained. Hard water, skipped maintenance and heavy use all shorten that. If yours is in that range and showing signs like rust-coloured water, rumbling or leaks, start planning for a replacement.
Can a tankless heater run my whole house? Yes, if it's sized for the number of fixtures you use at the same time. Larger households sometimes need a larger unit or, occasionally, two units. A plumber will ask how many bathrooms you have and how your family uses hot water before recommending one.
Is electric tankless a good option? Electric tankless units can work well for smaller homes or single points of use, but whole-house electric tankless often needs a significant electrical service upgrade. Many homes with gas service find gas tankless more practical. Your plumber can tell you what your home can support.
What size tank do I need? It depends on your household. A family that showers back to back in the morning needs more stored hot water than a couple who shower at different times. When replacing a tank, think about whether you regularly run out of hot water now. If you do, a larger tank or a tankless unit may be worth considering.
