In January 2026, Ottawa experienced a brutal “Deep Freeze” with temperatures plunging to −37.8°C. For many local homeowners who recently made the switch to heat pumps, this was the ultimate test.
The data is now in. Based on real-world feedback from Ottawa residents and the latest HVAC performance metrics, here is the definitive guide on why a secondary heat source isn’t just a “backup”—it’s a necessity for the capital region.
The Myth of “Full-Electric” at −30°C
Most high-end cold-climate heat pumps (like the Mitsubishi Zuba or Daikin SkyAir) are rated to provide heat even as cold as −30°C. In a “normal” winter, this covers about 90% of our season. However, 2026 reminded us that Ottawa doesn’t always play by the rules. For those homeowners that are using fully electric heat pump systems, they will see the heat pump running continuously with their backup electric running in tandem. For those with gas as a backup, they will see the heat pump shutting down in favour of gas heating.
The “Thermal Balance Point” Explained
Every home has a “Balance Point”—the outdoor temperature where the heat pump can no longer extract enough heat to offset what your home is losing through its walls and windows.
- In newer airtight homes: This might be −20°C.
- In older Westboro or Glebe homes: This can be as high as −6°C.
When you hit this point, your heat pump doesn’t just stop; it begins to run 24/7 without ever reaching your thermostat’s set point. This is where your second source of heat becomes the hero of the story. **Either supplementing the heat pump or taking over the heating requirements entirely**
Why a Second Heat Source is Critical
Based on our customer feedback from this past winter, there are three scenarios where the heat pump needs a “tag-team” partner:
1. The Defrost Cycle “Chill”
When it’s snowy and humid near the freezing mark, your outdoor unit’s coils will frost over. The system must enter “Defrost Mode,” effectively turning into an Air Conditioner for 5–10 minutes to melt the ice.
- Without a second source: Your vents blow cold air into your living room.
- With a second source: The backup heat kicks in instantly to “temper” that air, so you never feel the dip.
2. The Recovery Struggle
Heat pumps are “marathon runners,” not “sprinters.” If you like to lower your temperature to 17°C at night and want it back to 21°C by 7:00 AM, a heat pump alone will take hours to get there when it’s −15°C outside. A gas furnace or electric backup can bridge that gap in minutes.
3. Extreme Cold (The -30°C Barrier)
Once we hit the record-breaking lows of late January, most heat pumps physically cannot extract enough ambient heat to be efficient. At this point, the Coefficient of Performance (COP)—the measure of how much heat you get per dollar of electricity—drops toward 1.0 (the same as a space heater). Once the heat pump has lost efficiency it is often prudent to run your gas backup as it is a more economic choice.
The Winning Strategy: Dual-Fuel (Hybrid) Systems
For 2026, the clear favorite among Ottawa homeowners is the Hybrid (Dual-Fuel) System. This pairs an electric heat pump with a high-efficiency natural gas furnace.
| System Type | Best For | Ottawa Reality Check |
| Heat Pump + Electric Strips | Modern, highly insulated homes (Net Zero). | Can lead to “Hydro sticker shock” during a 2-week cold snap. |
| Heat Pump + Gas Furnace | 80% of Ottawa residential retrofits. | The Winner: Uses the heat pump for 90% of the year; switches to gas only during the “Deep Freeze” or during high-peak hydro hours. |
The Bottom Line: What Can You Actually Save?
While the environmental benefits of switching to a heat pump are clear, the financial impact depends heavily on your home’s specific needs and your current energy consumption. In Ottawa, as carbon taxes increase the cost of natural gas and new electricity programs like “Ultra-Low Overnight” pricing become available, the math is shifting.
On average, Ottawa homeowners who switch to a high-efficiency hybrid system see a reduction in their total energy bills of 20% to 40%. Use our 2026 estimator below to see how an upgrade could impact your wallet.
Energy Savings Estimator
*Estimates based on 2026 Ottawa utility rates. Dollar savings reflect the average offset of electricity costs vs. gas reduction. Carbon calculation based on average Ontario grid intensity.
2026 Rebates: What Can You Get Back?
Despite the federal Greener Homes Grant shifting, there are still significant incentives available in Ontario:
- Enbridge Home Efficiency Rebate Plus (HER+): Up to $10,000 for eligible Enbridge customers who install a cold-climate heat pump alongside other upgrades.
- Canada Greener Homes Loan: Still offering up to $40,000 interest-free over 10 years, making the higher upfront cost of these systems much easier to swallow.
- Manufacturer Rebates: Companies like Lennox and Daikin are offering seasonal rebates up to $1,500 for systems installed before the spring.
Final Verdict for Ottawa Residents
A heat pump is an incredible technology that can potentially save you 20-50% on annual energy bills. But in a city where the "Wind Chill" is a daily news headline, never go full electric without a robust backup plan. A hybrid system offers the "green" benefits of a heat pump for most of the year, with the "toasty" reliability of gas when the canal freezes over.
