- If you currently heat with oil or propane: heat pump conversion is almost always the right call. Operating costs drop 40–70% and OHPA rebates often cover most of the conversion cost.
- If you currently heat with natural gas and plan to stay 7+ years: a hybrid heat pump + gas furnace system is now the most common recommendation. Captures the full rebate stack, cuts operating costs, keeps gas reliability for cold snaps.
- If you're staying in the home short-term (under 5 years) or have major electrical/duct issues: a high-efficiency furnace replacement is often the more practical choice.
- "Heat pumps don't work in Ontario winters" is outdated. Modern cold-climate heat pumps deliver full capacity at -15°C and operate to -25°C and below.
The basic difference
A furnace burns fuel — natural gas, oil, or propane — to generate heat, then blows that heat through your ductwork. Combustion happens in a sealed chamber, and exhaust gases vent out a flue. Modern furnaces convert 80–98% of the fuel's energy into useful heat (the percentage is the AFUE rating).
A heat pump doesn't burn anything. It uses electricity to move heat from one place to another — from outdoor air into your home in winter, and from indoor air to outside in summer. It's the same basic technology as your refrigerator, scaled up. Because it's moving heat rather than generating it, a heat pump can deliver 2.5–3.5 units of heat energy for every unit of electricity it consumes.
That ratio is the heat pump's superpower. Even though electricity costs more per energy unit than natural gas, the multiplier means heat pumps end up cheaper to operate in most Ontario scenarios — and dramatically cheaper compared to oil or propane.
Side-by-side comparison
| Factor | Gas furnace | Cold-climate heat pump |
|---|---|---|
| Upfront cost (installed) | $5,500–$9,500 | $11,000–$22,000 before rebates |
| Net cost after rebates | $5,000–$8,500 | $5,500–$13,000 typical |
| Annual heating cost (typical Halton Hills home) | $1,200–$2,000 (gas) | $900–$1,500 (electricity) |
| Cooling capability | None — separate AC needed | Built-in, replaces AC |
| Lifespan | 15–20 years | 15–18 years |
| Cold weather performance | Constant output to any temperature | Full capacity at -15°C, reduced output below -25°C |
| Emissions (operational) | Direct combustion CO₂ | ~90% lower (Ontario grid is mostly clean) |
| Electrical service required | Standard 120V circuit | Dedicated 30–60A 240V circuit |
| Ductwork requirements | Standard residential ductwork OK | Slightly higher airflow — older homes may need duct additions |
| Maintenance | Annual furnace tune-up + AC tune-up | Annual heat pump service (one visit) |
| Rebate eligibility | $250–$1,500 typical | $4,000–$7,500 typical (oil-to-HP: $15,000+) |
Operating cost math
This is the question that decides most installations. The answer depends on your current heating fuel and Ontario's energy pricing.
Versus natural gas (96% AFUE furnace)
For a typical 2,000 sqft Halton Hills home, annual heating fuel:
- 96% AFUE gas furnace: ~80 GJ of natural gas per year × ~$15/GJ = ~$1,200/year
- Cold-climate heat pump: ~6,500 kWh of electricity per year × ~$0.155/kWh = ~$1,000/year
That's a ~17% operating cost reduction. Over 10 years of equipment life, the heat pump saves ~$2,000 in operating costs versus gas — modest but real, and that's before factoring in the cooling included for free.
Versus oil heating
Oil heating in Halton Hills is brutally expensive. A typical oil-heated home goes through 2,000–2,500 litres per year at $1.30–$1.60/litre, for total fuel cost of $2,600–$4,000/year. The heat pump replacement uses ~6,500 kWh = ~$1,000/year. Net savings: $1,600–$3,000 per year, which means the heat pump pays back its incremental cost in 3–6 years even before rebates.
Versus propane
Propane sits between oil and natural gas on cost. A typical propane-heated Halton Hills home spends $2,000–$3,200/year on heating. Heat pump replacement = $1,000/year. Annual savings: $1,000–$2,200, with payback typically in 5–8 years.
The numbers above use mid-2026 Ontario pricing. Natural gas prices have been relatively low; electricity prices are stable but trending up; oil and propane prices fluctuate substantially. The heat pump's advantage increases when fossil fuel prices rise, and decreases when they fall. Long-term trend in Ontario points to gradually narrowing fossil-fuel cost advantages — a heat pump installed today is also a hedge against future fuel price spikes.
Cold weather performance: the reality
The "heat pumps don't work in Ontario winters" claim is the most persistent myth in HVAC. It's based on equipment from 10+ years ago. Modern cold-climate heat pumps are an entirely different generation of technology.
Specifically, models like Mitsubishi Hyper-Heat, Daikin Aurora, Carrier Infinity, Trane XV20i, and Lennox Signature Cold Climate:
- Deliver 100% of rated heating capacity at -15°C
- Continue operating efficiently to -25°C and below
- Use variable-speed inverter compressors that adjust output to match heating load (rather than just on/off)
- Have integrated defrost cycles to handle frost on the outdoor coil
Halton Hills' winter design temperature — the temperature your heating system needs to cover — is -22°C. We see -25°C maybe 5–15 days a typical winter, and rarely below -30°C. Modern cold-climate heat pumps handle this without supplemental heat.
That said, performance does drop at extreme low temperatures. At -25°C, a heat pump might deliver only 60–75% of its rated capacity, and the COP (coefficient of performance) drops below the break-even point versus gas. Which brings us to the smart middle ground.
The hybrid option (and why we recommend it for most gas homes)
A hybrid system pairs a cold-climate heat pump with a gas furnace (new or existing). A smart thermostat — typically an ecobee Premium or similar — monitors outdoor temperature and automatically chooses the more efficient heat source moment to moment.
Above the "switchover temperature" (configurable, typically -10°C to -15°C), the heat pump runs. Below that, the system switches to the gas furnace. The result:
- Heat pump handles ~85–95% of annual heating hours in Halton Hills
- Gas furnace covers the coldest 5–15 days a winter when the heat pump's COP drops
- You get cooling included (no separate AC needed)
- Full Ontario rebate stack qualifies (the gas furnace doesn't disqualify the heat pump rebates)
- Total system reliability is better than either alone — two heat sources, automatic failover
For most gas-heated Halton Hills homes, hybrid is now the recommended configuration. More on heat pump installs.
Decision framework — which fits your situation?
Strong heat pump case (full electric or hybrid):
- Currently heat with oil or propane
- Existing furnace and AC are both at end of life (replace both at once with one heat pump)
- Plan to stay in the home 7+ years
- Have or are planning to install rooftop solar (heat pump pairs well with solar generation)
- Already have a 200-amp electrical service
- Care meaningfully about reducing home emissions
High-efficiency furnace makes more sense:
- Current AC is recently replaced (5 years or newer) and you don't want to scrap it
- Plan to sell the home in the next 3–5 years
- 100-amp electrical service with no plans to upgrade
- Significantly undersized ductwork that would need expensive modification for heat pump airflow
- Budget constraints make the higher upfront cost prohibitive even after rebates
Hybrid heat pump + gas furnace fits when:
- Currently gas-heated and want lower operating cost without giving up cold-snap reliability
- Want to capture full rebate stack while keeping gas heat as backup
- Replacing both furnace AND aging AC at same time
- Most common Halton Hills recommendation for homes with existing natural gas service
Frequently asked questions
Do heat pumps work in Ontario winters?
Modern cold-climate heat pumps (Mitsubishi Hyper-Heat, Daikin Aurora, Lennox Signature, Carrier Infinity) deliver full rated capacity at -15°C and continue working efficiently to -25°C and below. Halton Hills' design temperature is -22°C, well within operating range. The 'heat pumps don't work in cold weather' line is based on equipment from 10+ years ago — modern systems are a different generation.
Is a heat pump cheaper to operate than a gas furnace?
Yes, in most Ontario scenarios. Modern cold-climate heat pumps deliver 2.5–3.5 units of heat for every unit of electricity consumed, which more than compensates for electricity being more expensive per energy unit than natural gas. Typical Halton Hills home: heat pump operates roughly 15–25% cheaper than a 96% AFUE gas furnace year-round. Compared to oil heat, savings are 50–70%. Compared to propane, 40–60%.
What is a hybrid heat pump system?
A hybrid system pairs a cold-climate heat pump with a gas (or oil/propane) furnace, controlled by a smart thermostat that automatically chooses the more efficient heat source based on outdoor temperature. Below a 'switchover temperature' (typically -10°C to -15°C), the gas furnace takes over. Above that, the heat pump runs. Hybrid systems qualify for the full Ontario rebate stack and are the most common recommendation for gas-heated Halton Hills homes.
Will my electrical panel handle a heat pump?
Most modern 200-amp panels handle a heat pump install without modification. Older 100-amp panels often need either a panel upgrade or a load management device, which adds $1,800–$3,500 to project cost. The contractor should assess this during the in-home consultation — there should be no surprise after install.
Should I replace my old furnace with another furnace or switch to a heat pump?
The deciding factors are: (1) your existing heating fuel (oil and propane homes have stronger heat pump economics than gas-heated homes), (2) how long you plan to stay in the home (heat pumps have higher upfront cost but lower operating cost — payback typically 5–10 years), (3) your existing ductwork and electrical capacity, and (4) your priorities around emissions and resilience. For most gas-heated Halton Hills homes staying 7+ years, a hybrid heat pump system is now the smarter long-term choice.
What's the difference between SEER and HSPF for heat pumps?
SEER (Seasonal Energy Efficiency Ratio) measures cooling efficiency. HSPF (Heating Seasonal Performance Factor) measures heating efficiency. Both higher = more efficient. For Ontario installs, look for HSPF 10+ and SEER2 17+. Cold-climate certification (CCHP rating) is a separate designation indicating verified performance at low temperatures — that's the rating that matters for our climate.
If you're trying to decide between options for your specific home, we do free in-home assessments — proper Manual J heat-loss calculation, electrical assessment, and side-by-side option pricing with rebate stacks. Book one here. No high-pressure sales — we'll genuinely tell you which path fits your situation.