The GTA Homeowner's
Furnace Buyer's Guide.
Types, efficiency ratings, sizing, costs, and which brands are actually worth it.
How Does a Gas Furnace Work?
This GTA homeowner's furnace buyer's guide walks you through how modern gas furnaces work, how to size one for your home, AFUE efficiency tiers, real install costs, Ontario rebate reality, and the brands we actually install after 17+ years in the Toronto area.
A gas furnace heats air using a burner and heat exchanger, then pushes that warm air through your home's ductwork with a blower motor. A thermostat signals when to turn on and off.
Modern furnaces have electronic ignition (no standing pilot light), variable-speed blowers for quieter operation, and secondary heat exchangers that squeeze more heat from exhaust gases — which is why newer models can hit 98% efficiency compared to 60-70% for furnaces from the '90s.
In the GTA's climate, your furnace is your most important appliance. It runs 5-7 months a year. Choosing the right one affects your comfort, energy bills, and home value for the next 15-20 years.
When Should You Replace Your Furnace?
Not every furnace problem means you need a new one. But there are clear signs it's time. Here's how we think about it as technicians:
- ✕ Over 15-20 years old
- ✕ Repair costs exceed $500 on an older unit
- ✕ Cracked heat exchanger (safety issue)
- ✕ Energy bills rising despite maintenance
- ✕ 3+ repairs in the last 2 years
- ✓ Under 12 years old
- ✓ First-time repair on a newer unit
- ✓ Simple fix — ignitor, flame sensor, blower motor
- ✓ Repair cost is under 30% of replacement
- ✓ You're not planning to sell the house soon
Need help deciding? Book a diagnostic — our technicians will give you an honest recommendation, not a sales pitch.
Three Types of Gas Furnaces
Every gas furnace falls into one of three categories. The right choice depends on your budget, your home's size, and how much you care about noise and energy bills.
Single-Stage
One speed: full blast. Simple, reliable, affordable. Runs at 100% capacity every time it turns on.
- Lowest upfront cost
- Simple and proven technology
- Easy to repair
- Louder than other types
- Bigger temperature swings
Two-Stage
Two speeds: low for mild days, high for deep cold. Better comfort, quieter, and more efficient than single-stage.
- Runs on low 80% of the time
- More even temperatures room-to-room
- Significantly quieter operation
- Better humidity control
- Best balance of cost vs comfort
Modulating
Adjusts output in 1% increments — like cruise control for your furnace. Whisper-quiet and maximum efficiency.
- Near-silent operation
- Rock-steady temperatures
- Lowest energy bills
- Works with smart thermostats
- Highest upfront investment
Our recommendation for most GTA homes: two-stage furnace, 96% AFUE. Best bang for the buck. See our furnace lineup →
Getting the Right Size Furnace
An oversized furnace short-cycles (turns on and off too frequently), wastes energy, and wears out faster. An undersized one can't keep up on the coldest days. Proper sizing matters more than brand.
Furnaces are measured in BTUs (British Thermal Units) of heating output. The right size depends on your home's square footage, insulation, windows, ceiling height, and orientation.
These are estimates only. A proper heat-loss calculation considers insulation, windows, and air leakage.
Technician doing heat-loss assessment
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An oversized furnace heats your home too quickly, then shuts off — only to turn on again minutes later. This "short cycling" wastes gas, wears out parts faster, and creates uncomfortable temperature swings.
We do a proper heat-loss calculation for every installation — not a guess based on square footage.
Understanding AFUE Ratings
AFUE (Annual Fuel Utilization Efficiency) measures how much of the gas your furnace burns actually becomes heat in your home. A 96% AFUE furnace turns 96 cents of every gas dollar into heat — only 4 cents goes up the exhaust.
In Ontario, the minimum AFUE for new furnace installations is 95% (as of 2023 building code changes). Most furnaces sold in the GTA today are 96-98% AFUE.
GTA math: If you're replacing a 70% furnace with a 96% furnace, you'll use about 27% less gas.
Actual savings depend on your current equipment's AFUE, your home's envelope, and your gas rate. Real-world GTA savings after a 70%→96% upgrade usually fall between $400–$800/year on gas bills that currently run $1,800–$3,200.
How Much Does a New Furnace Cost?
The total cost of a furnace installation includes the unit itself, labour, permits, and any ductwork modifications. Here's what GTA homeowners typically pay in 2026:
We get asked about rebates on every quote, so here's the straight answer: there is currently no meaningful rebate for a standalone gas furnace in Ontario. The Canada Greener Homes Grant closed to new applicants in early 2024, and the Enbridge HER+ program closed in February 2024.
Ontario's Home Renovation Savings Program (HRSP) is active through November 2026 — but it's heat-pump-focused. A 96% AFUE furnace on its own doesn't qualify.
If you want rebate money and high-efficiency heating, a hybrid (dual-fuel) setup — furnace + heat pump — lets you claim the HRSP heat pump rebate (up to $7,500) while keeping gas backup for the coldest GTA days. See our heat pump buyer's guide →
Financing available: We offer monthly payment plans through Financeit. Many GTA homeowners pay $50–$80/month for a new high-efficiency furnace — less than the energy savings it provides. Call for details.
The Three Brands We Install — And Why
H&C is an official dealer of three furnace brands. We picked them deliberately: one covers best-in-class value, one covers premium, one covers budget. Between them, they fit every GTA home we see. All gas furnace work in Ontario requires TSSA licensing — we've been TSSA-licensed since 2008.
We also service Carrier, Bryant, Trane, York, Daikin, and most other major brands — we just don't install them new. H&C is already an official dealer of Keeprite, Lennox, and Goodman; being a dealer of every brand isn't possible or useful.
Every brand makes good and bad models. The brand matters less than: proper sizing, quality installation, and regular maintenance. See our recommended models →