Walk onto almost any job site these days and you’ll hear somebody talking about tankless water heaters. They’re popping up in homes, condos, even small commercial jobs all over Ontario and Quebec. Why? Simple: clients like the idea of never running out of hot water, and they love that these things don’t hog half the basement like an old tank.
Now, if you’re a contractor, you already know the conversation always goes the same way. The client says: “I heard tankless is the way to go. Just put in the biggest one you’ve got so we don’t run out.” But that’s not how it works. Pick the wrong size or type, and you’ll get callbacks you don’t want. Let’s break it down so you can match the right unit to the right project.
Sizing: Where Most People Mess Up
Tankless heaters don’t store hot water. The second the tap turns, they fire up and heat it on the spot. That means everything depends on flow rate, measured in gallons per minute (GPM).
Here’s the real-world version:
- Small bungalow, one bathroom? A 6–7 GPM unit is fine.
- Big house with three showers, dishwasher, and laundry running at once? You’ll need 9–11 GPM.
- Multi-unit or light commercial? Don’t be a hero with one big box. Put a few units in cascade. It’s easier to service later too.
I’ve seen jobs where the wrong size was installed, and the family couldn’t run the dishwasher without freezing someone in the shower. Trust me, you don’t want to get that call.
Efficiency: Not Just Sales Talk
Some guys roll their eyes when they hear “high efficiency,” but here’s the deal: it matters. Tankless units usually come in two flavors.
- Non-condensing: Cheaper up front. They vent out hotter air, which means you need stainless venting.
- Condensing: Capture heat from exhaust, push efficiency over 90%, and let you use PVC venting.
Sure, condensing costs a bit more, but clients see the difference every month on their bills. Plus, it’s a lot easier to sell when you remind them Canada’s pushing for better energy standards anyway.
Things You Gotta Check Before Installing
Here’s a quick contractor checklist. Skip this and you’ll regret it:
- Venting: Some models give you flexible options, which is gold for retrofit jobs.
- Gas line: Most tankless need a bigger line than tanks. Check first. Nothing worse than realizing it too late.
- Water quality: Hard water means scale, and scale kills efficiency. A softener or treatment system can save the client a lot of grief.
- Maintenance: Make sure the model isn’t a nightmare to service. You’ll thank yourself later.
- Warranty: Long warranty = less stress for you when something goes wrong.
Brands You Can Trust
At Nordics, we don’t bother with products that leave contractors hanging. Here are three brands we keep stocked and recommend:
Noritz
A pioneer in tankless technology, Noritz has built a reputation for durability and innovation. Their condensing units achieve exceptional efficiency while offering flexible venting options and compact designs. For contractors, Noritz units are straightforward to install and backed by solid warranties—making them a trusted choice for both residential and light commercial projects.
Viessmann
German engineering at its finest. Viessmann makes premium gear, built for clients who want quality that lasts. Great efficiency, steady hot water, and designed to integrate nicely into hydronic systems.
IBC
Another Canadian company, and honestly, their units are tough. They handle our winters without blinking, and contractors like the local support. Durable, efficient, and built for real-world conditions.
New Builds vs. Retrofits
Tankless works great in both situations, but the approach is different.
- New builds: Easy mode. Plan the gas, venting, and placement right from the start. Saves time and usually money. Plus, tankless frees up space, and clients notice that.
- Retrofits: A bit trickier. You might have to run a new gas line or rethink the venting. But once it’s in, clients love it—no more running out of hot water, smaller footprint, and better bills.
Wrapping It Up
Bottom line? Picking the right tankless isn’t about finding the biggest, flashiest model. It’s about matching the unit to the demand, the install conditions, and the client’s expectations. Get it right and you’ll have happy clients and fewer callbacks.
At Nordics, we’ve got Noritz, Viessmann, and IBC tankless water heaters ready for contractors who want equipment they can trust. Whether you’re working on a new build or replacing an old tank, we’ve got the stock and the support to back you up.
Need help finding the right tankless unit for your next job?
Get in touch with Nordics—we’ll point you in the right direction.
