Boiler Replacement Cost Toronto

Boiler replacement cost in Toronto for a high-efficiency condensing boiler typically runs $6,645 to $17,431 installed, and a combi boiler (heat and hot water in one unit) runs $7,327 to $12,910 installed, depending on the brand, size and your home.

These are Bison Air's real installed prices for NTI, Navien and Viessmann boilers across Toronto and the GTA, not national averages. Below you will see what is included, what can add to the price, and how to choose between a combi boiler and a boiler with a hot water tank. For full details on our work, see Boiler Installation Toronto and Combi Boiler Installation Toronto.

Old boiler and hot water tank before boiler replacement in a Toronto home — **Before:** old boiler plus a separate gas water tank.

NTI TRX Series II condensing boiler after replacement by Bison Air in Toronto — **After:** NTI TRX Series II wall-hung condensing boiler.

✓ Real installed prices: every model below has its own page with sizes and pricing
✓ TSSA-certified gas technicians, licensed, insured and specialized in hydronic heating
✓ Heat-loss sizing, so you don't pay for an oversized boiler
✓ 1-year labour warranty on every installation, plus the manufacturer's warranty
✓ Financing available, with no upfront payment options

💲 Boiler Replacement Cost by Type

Boiler type	Best for	Installed price
Heat-only condensing boiler	Radiators, baseboard, radiant floors	$6,645 – $17,431
Combi boiler	Small to medium homes; replacing a boiler and a separate water tank	$7,327 – $12,910
Indirect hot water tank (add-on)	Heat-only boilers in homes with 2+ bathrooms	$4,474 – $9,608
Commercial boiler	Multiplexes, small commercial buildings	$15,499 – $20,446

Prices include standard installation and are current as of 2026. Your final price is confirmed in a written quote after we see your home.

🏷️ Installed Prices by Brand & Model

Each model page shows every size, its specs and its installed price:

Model	Type	Installed, from
Navien NHB	Heat only	$6,645
Navien NCB-H	Combi	$7,327
Navien NFB	Heat only (fire tube)	$7,658
NTI TRX Series II	Heat only / Combi	$8,491 / $9,527
Navien NFC-H	Combi (fire tube)	$9,200
NTI FTVN Series II	Heat only / Combi	$9,473 / $10,948
Viessmann Vitodens 100-W	Heat only / Combi	$10,100 / $11,768
NTI TFTN Premium	Heat only	$11,403
Viessmann Vitodens 200-W	Heat only	$12,985
NTI Trin & Stor / Viessmann Vitocell	Indirect tank	$4,474

Browse every model in our Boilers & Combi Boilers collection.

✅ What Standard Installation Includes

✓ Removal of your old boiler
✓ Installation of the new boiler, connected to your existing heating system
✓ Startup, commissioning and controls setup
✓ 1-year labour warranty and warranty registration

💡 Replacing an existing high-efficiency boiler? A high-efficiency to high-efficiency replacement typically needs no extras, because the venting and piping are already in place.

➕ What Can Add to the Cost

Every home is different. These items are quoted separately when your job needs them:

✓ New or replaced boiler accessories: feeder valve, circulator pumps, backflow preventer, air separator, dirt separator
✓ New venting longer than 20 ft (common when an old atmospheric boiler used the chimney)
✓ Extra plumbing or re-piping changes
✓ Difficult job sites, such as crawl spaces or tight mechanical rooms
✓ Adding heating zones or an indirect hot water tank
✓ Gas line changes

We list every extra on your written quote before any work starts, so there are no surprises.

Old atmospheric boiler and gas water tank before replacement in a Toronto basement — **Older atmospheric boiler:** often needs new venting when replaced.

NTI wall-hung boiler with expansion tank and zone manifold installed by Bison Air in Toronto — Expansion tank, pumps and manifolds are replaced only if needed.

⚖️ Combi Boiler vs Boiler + Hot Water Tank: Which Costs Less?

✓ Combi boiler: one unit for heat and on-demand hot water. Lower upfront cost, no tank to rent or replace, and it frees up space. Best for condos and homes with 1 to 2 bathrooms.
✓ Heat-only boiler + indirect tank: higher upfront cost, but a large stored hot water supply for homes with 2+ bathrooms or large tubs.

Many Toronto homeowners replace an old boiler and a rented gas water tank with a single combi boiler and stop paying the monthly rental. See Combi Boiler Installation Toronto.

Navien combi boiler replacement by Bison Air in Toronto — **Combi:** Navien combi boiler, heat and hot water in one unit.

NTI boiler with indirect hot water tank installed by Bison Air in Toronto — **Boiler + tank:** NTI boiler with an indirect hot water tank.

📸 Recent Boiler Replacements

NTI condensing boiler replacement with zone piping by Bison Air in Toronto — NTI boiler with new zone piping.

NTI boiler with indirect water heater installed by Bison Air in the GTA — NTI boiler paired with an indirect water heater.

Navien combi boiler with Airmax hydronic air handler installed by Bison Air in Toronto — Navien combi feeding a hydronic air handler for forced-air heat.

Navien high-efficiency boiler installation by Bison Air in Toronto — Navien high-efficiency boiler installation.

NTI condensing boiler with indirect water heater installed by Bison Air in Toronto — NTI boiler with an indirect tank and clean copper piping.

Multiple NTI boilers in a commercial boiler installation by Bison Air in Toronto — Multi-boiler commercial installation.

More real projects are on our project blog.

📊 What Affects Your Boiler Price

✓ Brand and model: Navien NHB and NCB-H are the most cost-effective; NTI TFTN and Viessmann 200-W are premium
✓ Size: sized to your home's heat loss, from small homes to very large homes
✓ Heat only or combi, and whether you need an indirect tank
✓ Your existing system: venting, piping and accessories that can be reused
✓ Job site access

🔧 How We Quote Your Boiler Replacement

In-home assessment: we check your current boiler, piping, venting, gas line and hot water needs.
Heat-loss sizing: the new boiler is sized to your home, not to the old unit.
Clear written quote with model, scope, any extras and timeline, plus financing if you want it.
Installation, startup and commissioning: every zone tested before we leave.
Walkthrough and warranty registration.

💡 Spread the cost: HVAC financing turns your boiler replacement into monthly payments. Want air conditioning too? A hydronic air handler or ductless heat pump can be quoted with your boiler.