Quebec winters, with their extreme cold and fluctuating temperatures, raise an important question for many homeowners with a central heat pump: should it keep running all winter long, or should it be shut off temporarily? At AirGreen, we get asked this every year, especially by clients in Montreal, Laval, Longueuil, on the North Shore and the South Shore. In this article, we’re offering a clear answer based on our field expertise, technical insight, and the best practices in the HVAC industry.
Understanding How a Central Heat Pump Works in Winter
Unlike traditional air conditioners, a central heat pump is designed to heat and cool your home depending on the season. In heating mode, it extracts heat energy from the outside air (even when it’s cold) and delivers it indoors.
Modern models — such as units by Fujitsu, Bosch BOVA, Goodman R-32, Gree FLEXX, Arcoaire, Comfortmaker, or even Trane — are engineered to perform efficiently at temperatures as low as -25 °C, even -30 °C, depending on the technology used. These are therefore very effective winter systems, as long as they are well maintained and properly installed.
Is It a Good Idea to Turn Off Your Central Heat Pump in Winter?
No — except in specific cases.
The vast majority of central heat pumps installed by AirGreen across the Greater Montreal area are built to keep operating even during deep freezes. However, certain specific situations do warrant a closer look.
Here are a few scenarios where you might consider temporarily shutting off your heat pump:
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Temperatures below the unit’s rated capacity: Some older heat pumps lose efficiency starting around -15 °C. In such cases, a furnace or backup system may need to take over.
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Frost or ice buildup: If the outdoor unit is clogged or blocked, it may freeze up. A temporary shutdown may be needed for manual defrosting or inspection.
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Malfunctioning automatic defrost system: A properly working system will initiate automatic defrost cycles. If not, you should call a professional to prevent further damage.
Why It's Better to Let Your Heat Pump Run Continuously
1. Optimized Energy Consumption
When your heat pump is properly sized for your home (which we always ensure during our HVAC installations), it consumes less energy than traditional electric heating systems. Turning it off only forces your backup system to work harder — which can increase your hydro bill.
2. Better Indoor Comfort
A central heat pump operates in a continuous, gradual manner, maintaining a stable indoor temperature. Turning it off disrupts that stability, especially in large spaces or poorly insulated buildings.
3. Prevents Overuse of Auxiliary Heating
Turning off the heat pump forces the electric furnace to run at full capacity, often causing intense and uneven heat cycles that are less comfortable.
The Importance of Proper Winter Maintenance
At AirGreen, we always stress the importance of regular maintenance, especially heading into winter. During our service calls in South Shore, Laval, or Boisbriand on the North Shore, we’ve seen firsthand that poorly maintained units are the number one cause of poor winter performance. Our recommendations:
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Regularly clear the area around your outdoor unit (leaves, snow, ice).
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Check indoor vents and ducts to ensure proper airflow.
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Schedule a professional HVAC maintenance visit every year: At AirGreen, we offer a full-service inspection, including coil cleaning, defrost sensor checks, and performance testing.
Which Central Heat Pumps Perform Best in Winter?
Among the brands we install, some stand out for their winter reliability:
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Bosch BOVA IDS Premium (R-454b): ultra-quiet, high-efficiency, works even in extreme cold with Inverter technology.
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Fujitsu KZAH (R-32): excellent energy rating, very popular in Longueuil and Repentigny for its ability to heat down to -26 °C.
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Goodman R-32 with high-efficiency compressor: rugged and economical, particularly suited for mid-size homes in Laval and Brossard.
All of these units are eligible for government incentives, including Hydro-Québec’s LogisVert program, offering rebates up to $5,000, depending on your system configuration.
Customer Testimonial in Montreal: Smooth Performance Even at -28 °C
Recently, our team installed a Bosch BOVA IDS 2.0 central heat pump in a century-old home in Plateau Mont-Royal. Despite an especially frigid winter, the customer never had to activate their backup electric furnace. Thanks to our custom installation, proper sizing, and upgraded insulation, the comfort level remained steady all winter.
AirGreen Expert Tips: Do’s and Don’ts
Do:
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Let your heat pump run even at -20 °C (if your unit allows).
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Check weekly for snow or ice buildup around the outdoor unit.
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Schedule a professional HVAC checkup before winter.
Don’t:
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Don’t manually cut power to the unit without a technical reason.
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Never use sharp objects to remove snow — this can damage the coil fins.
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Don’t ignore strange noises or excessive defrost cycles.
In Summary: Turn Off or Not?
The answer is no, in 90% of cases. A well-maintained, well-installed heat pump designed for Quebec winters can — and should — stay on all season to maximize comfort and reduce energy usage. At AirGreen, we ensure every client gets a system tailored to their needs, backed by reliable technical support year-round.