A ducted heat pump is a central heating and cooling system that moves heat between the outdoors and indoors using refrigerant, distributing conditioned air throughout your home through your existing duct system — exactly the way a furnace and central air conditioner currently do. The difference is that a single heat pump unit does the job of both, without burning any fuel.

In winter, the heat pump extracts thermal energy from outdoor air — even at -25°C or colder — and delivers it inside as warm air through your vents. In summer, it reverses the process, pulling heat out of your indoor air and releasing it outside, functioning identically to a central air conditioner. One outdoor unit, one indoor air handler, one duct system, one thermostat — full year-round comfort.

For most Ontario homeowners, a ducted heat pump is purchased as a direct replacement for an aging furnace and central air conditioner. If your existing equipment is 10 to 15 years old or older, a ducted heat pump is often the most economical and environmentally responsible replacement path — particularly when Ontario and federal rebates are factored into the cost comparison.

Ducted heat pumps are not the right choice for every home. Here is an honest assessment of when a ducted system makes strong sense and when a different approach may be better:

Ducted Heat Pump Is a Strong Fit When:

• Your home has an existing forced-air duct system in reasonably good condition
• Your furnace and central air conditioner are aging and due for replacement at the same time
• Your ductwork is well-distributed throughout the home, reaching all living areas
• You want whole-home heating and cooling from a single, centrally controlled system
• You prefer a concealed installation with no wall-mounted units visible in living spaces
• You are planning a major renovation that includes HVAC upgrades
• You want to take advantage of Ontario and federal rebates for heat pump installations
• You are interested in reducing your home's carbon footprint and energy consumption

Consider Alternatives When:

• Your home has no existing ductwork and adding ducts would be impractical or prohibitively expensive — a ductless heat pump is likely the better solution
• Your ductwork serves only part of your home and significant areas are unducted — a combination of ducted and ductless systems may be the optimal approach
• You only need heating and cooling for one specific room or zone — a single-zone ductless system is more cost-effective
• Your ductwork is in very poor condition and replacement would cost more than the value it provides — evaluate the full picture carefully with a professional assessment

If you are unsure which approach is right for your home, a Constant Home Comfort in-home consultation will give you a clear, honest recommendation based on your specific property — at no cost and no obligation.

This step is unique to ducted systems and is one that many buyers underestimate in importance. Your ductwork is not just a passive channel — it is an active part of the system's performance. A heat pump installed on a duct system that is poorly sealed, incorrectly sized, or in poor condition will never deliver the comfort or efficiency it was designed to provide, regardless of how good the equipment is.

Here is what your ductwork assessment should cover:

• Duct leakage: Most older duct systems lose 20 to 30% of conditioned air through gaps, poor connections, and deteriorated sealing tape. Heat pumps move larger volumes of air than gas furnaces, which means duct leakage has a more pronounced impact on performance. Sealing leaky ducts is often one of the highest-return investments a homeowner can make alongside a heat pump installation.
• Duct sizing: Heat pumps operate at lower supply air temperatures than gas furnaces and compensate by moving more air volume. If your ducts are undersized for the airflow a heat pump requires, you may experience noise, uneven comfort, or reduced efficiency. Duct sizing is evaluated as part of the Manual J load calculation and system design.
• Duct insulation: Ducts that run through unconditioned spaces — attics, crawlspaces, unfinished basements — should be insulated to prevent energy losses. This is especially important for heat pumps, which deliver air at lower temperatures than a gas furnace.
• Duct distribution: Are there rooms in your home that are currently too hot in summer or too cold in winter? This may indicate airflow imbalances in your duct system. These can often be addressed through damper adjustments, duct additions, or supply register modifications — but they should be identified before the new system is designed.

At Constant Home Comfort, every ducted heat pump consultation includes a ductwork assessment. If remediation work is recommended, we'll be specific about what's needed, why it matters, and what it will cost — so you can make an informed decision about whether to proceed with duct improvements alongside your heat pump installation.

Ducted heat pump systems can be configured in two primary ways, and the right choice depends on your home, your existing equipment, and your risk tolerance for cold-weather performance.

Heat Pump Only (Full Replacement)

A cold-climate ducted heat pump installed as the sole heating and cooling system — replacing both the furnace and central air conditioner entirely. This is the cleanest, most streamlined configuration. Modern cold-climate heat pumps from Lennox, Daikin, Bosch, and American Standard maintain full heating capacity at -25°C or lower, making this configuration viable for all but the most extreme Ontario locations.

This option is best for: homes with adequate insulation and air sealing, homeowners who want to eliminate gas costs and simplify their HVAC to one system, and those who want to maximize rebate eligibility and long-term efficiency.

Dual-Fuel System (Heat Pump + Gas Furnace Backup)

A ducted heat pump installed alongside your existing gas furnace, with both systems controlled by a compatible thermostat. The heat pump handles the vast majority of the heating load throughout the season — operating far more efficiently than the gas furnace across moderate and even fairly cold temperatures. Below a set outdoor temperature threshold (typically -15°C to -20°C), the system automatically switches to the gas furnace for backup heating.

This option is best for: homeowners with a relatively new gas furnace they don't want to retire immediately, those in particularly exposed or poorly insulated homes who want the reassurance of a gas backup, or buyers who want the efficiency benefits of heat pump operation for most of the year while retaining familiarity of gas heating at the extremes.

Dual-fuel systems are also a practical entry point for homeowners who want to transition toward full electrification over time — starting with a heat pump paired to an existing gas furnace, with the plan to remove the gas system at the furnace's natural end of life.

Correct sizing is one of the most critical — and most frequently mishandled — aspects of any HVAC installation. With ducted heat pumps, the stakes are high: an undersized system will struggle to maintain comfort on the coldest or hottest days, while an oversized system will short-cycle, causing poor dehumidification in summer, temperature swings, increased wear, and wasted energy.

Sizing is expressed in tons of capacity (1 ton = 12,000 BTU per hour). Residential ducted systems typically range from 1.5 tons for a smaller home or condo to 5 tons for a large house. The correct size for your home is determined through a Manual J heat load calculation — a formal engineering assessment that accounts for:

• Total conditioned floor area and ceiling heights
• Wall, ceiling, and floor insulation levels
• Window area, orientation, and glazing type
• Air infiltration and home airtightness
• Local climate data, including design temperatures for your Ontario location
• Internal heat gains from occupants, appliances, and lighting
• Duct system characteristics and distribution efficiency

At Constant Home Comfort, we perform a proper Manual J calculation before recommending any system. We never size by rule of thumb, and we'd encourage you to walk away from any contractor who quotes you a system size without conducting a thorough assessment of your home.

Ducted heat pumps are rated by two seasonal efficiency metrics that every buyer should understand before comparing systems:

HSPF2 (Heating Seasonal Performance Factor 2): Measures the system's heating efficiency across an entire season, accounting for variable outdoor temperatures and defrost cycles. A higher HSPF2 means more heat delivered per unit of electricity consumed. The current minimum for cold-climate certification is HSPF2 8.5; premium systems from Lennox, Daikin, and others achieve HSPF2 of 10 or higher. For context, a gas furnace operating at 96% efficiency has an effective HSPF2 equivalent of roughly 9.5 at current Ontario gas prices — a high-efficiency heat pump exceeds this while running entirely on electricity.

SEER2 (Seasonal Energy Efficiency Ratio 2): Measures cooling efficiency across an entire season. Premium ducted heat pumps achieve SEER2 ratings of 18 to 22+, comparable to or exceeding dedicated high-efficiency central air conditioners. A higher SEER2 translates directly to lower electricity costs during Ontario's increasingly warm summers.

Higher efficiency costs more upfront but pays back through lower monthly energy bills over the system's 15 to 20-year lifespan. When rebates are factored in — which are larger for higher-efficiency systems — the premium for a top-tier model is often recovered within a few years through energy savings alone.

Note: as of January 2023, efficiency ratings in Canada shifted to the SEER2 and HSPF2 standards, which use test conditions that more accurately reflect real-world installation conditions. When comparing systems or reading older documentation, confirm which standard is being referenced.

This is the single most important technical specification for Ontario homeowners, and it is the one most commonly glossed over in sales conversations. Not all heat pumps perform the same in cold weather, and the difference between a standard model and a genuine cold-climate model is significant.

Standard heat pumps begin losing heating capacity below 0°C and many older or budget models stop providing meaningful heat output below -10°C to -15°C. In Ontario — where overnight temperatures regularly fall to -15°C to -25°C across much of the province — a standard model simply cannot serve as a primary heating system without a fossil fuel backup running a significant portion of the time.

Cold-climate heat pumps are engineered with enhanced vapor injection compressor technology, optimized refrigerant circuits, and advanced defrost control systems that allow them to maintain full or near-full heating capacity at outdoor temperatures as low as -25°C to -30°C. For most Ontario homes, a properly sized cold-climate heat pump operates comfortably as the sole heating source throughout the winter.

When evaluating any ducted heat pump for Ontario installation, look for:

• Rated heating capacity at -15°C and -25°C: A genuine cold-climate system maintains 75 to 100% of its rated capacity at these temperatures. Verify this in the manufacturer's extended performance data, not just the rated capacity figure at standard test conditions.
• HSPF2 rating of 8.5 or higher: The Cold Climate Air Source Heat Pump (CCASHP) specification requires a minimum HSPF2 of 8.5 and verifiable capacity at low temperatures. This certification is required to qualify for most Ontario rebate programs.
• Minimum operating temperature: Confirm the system's rated minimum operating temperature. The best cold-climate systems from Lennox, Daikin, Bosch, and American Standard operate reliably to -25°C or -30°C.

Every ducted heat pump system recommended by Constant Home Comfort meets cold-climate specifications appropriate for Ontario's winters. We do not install equipment that we would not stand behind in a January cold snap.

The brand you choose affects your system's efficiency ceiling, cold-climate performance, reliability record, warranty terms, and the long-term support network available to you. Here is an honest assessment of each brand we carry:

Lennox

Lennox is one of the most respected names in North American HVAC and their ducted heat pump lineup reflects that position. Their top models — including the XP25 and XP21 series — achieve the highest HSPF2 and SEER2 ratings in the market, operate reliably to -30°C, and integrate seamlessly with the iComfort smart thermostat and home automation platforms. Lennox uses their proprietary Precise Comfort inverter compressor technology for exceptionally smooth, quiet, and efficient operation. Build quality, component selection, and factory testing standards are consistently high. Backed by a strong warranty and a robust national service network.

Best for: homeowners who want the best-performing system available, plan to stay in their home long-term, have a larger home with a significant heating load, and want to minimize lifetime energy costs regardless of upfront investment.

Daikin

Daikin's position as the world's largest HVAC manufacturer is built on genuine technical leadership — they invented many of the inverter compressor technologies that the industry now uses broadly. Their ducted heat pump lineup brings that expertise to Canadian homes with ENERGY STAR certified systems, impressive cold-climate performance, advanced variable-speed compressor control, and reliability backed by Daikin's global manufacturing standards and quality processes. Daikin consistently offers excellent efficiency at a price point that is somewhat more accessible than Lennox, making them one of the strongest value propositions in the premium heat pump segment.

Best for: homeowners seeking top-tier performance and reliability from a proven global manufacturer, who want high efficiency without paying for the absolute premium of the market's top model.

Bosch

Bosch HVAC applies the engineering discipline of one of the world's most respected industrial manufacturers to the North American heat pump market. Their IDS (Inverter Ducted Split) heat pump lineup is known for quiet, precise, reliable operation — characteristics that reflect Bosch's broader engineering heritage. Cold-climate performance is solid, efficiency ratings are competitive, and build quality is consistent with what Bosch customers expect across all their product categories. Bosch is a particularly strong choice for homeowners who value engineering quality as a primary criterion and prefer a system that works well without drawing attention to itself.

Best for: homeowners who prioritize engineering quality, reliability, and quiet operation, and who may be less focused on having the highest efficiency rating in the market than on having a system that consistently performs well across Ontario's full climate range.

American Standard

American Standard has been a trusted name in North American HVAC for over a century, and their ducted heat pump lineup reflects that heritage: solid efficiency ratings, dependable cold-climate performance, comprehensive warranty coverage, and competitive pricing. American Standard systems are well-suited to Ontario's climate and are a strong choice for homeowners who want proven, reliable technology from an established brand without paying for premium tier efficiency ratings they may not fully recoup in energy savings over the system's lifespan.

Best for: homeowners replacing an aging furnace and air conditioner on a defined budget who want a reliable, quality system from a trusted brand — without compromise on durability or cold-weather capability.

A ducted heat pump is only as good as its installation. Improper installation — incorrect refrigerant charge, poor electrical connections, inadequate duct assessment, wrong control wiring for a dual-fuel configuration — can result in a system that underperforms, fails prematurely, and voids your manufacturer warranty. Here is what a complete, professional installation from Constant Home Comfort includes:

• In-home assessment and Manual J sizing calculation: Confirms correct system size, identifies ductwork issues, and informs the full system design before any equipment is ordered.
• Removal and disposal of existing equipment: Responsible removal of your old furnace, central air conditioner, and associated components — including refrigerant recovery by a licensed technician.
• Outdoor unit installation: Mounted on a level concrete pad or wall bracket, positioned for optimal airflow, minimal noise impact on neighbours, and protection from prevailing weather.
• Indoor air handler installation: Installed in your utility room, basement, or designated mechanical space and connected to your existing duct system. Proper airflow balance across supply and return ducts is confirmed.
• Refrigerant line installation: Line sets are properly sized, insulated, supported, and weather-sealed between the indoor and outdoor units.
• Electrical connection by a licensed electrician: Including dedicated circuit installation, breaker sizing, and disconnect installation to code. Panel upgrades are included in the quote if required.
• Thermostat installation and configuration: Including smart thermostat setup, dual-fuel control wiring if applicable, and integration with home automation systems if desired.
• System commissioning: Refrigerant charge verification using manufacturer specifications, leak testing, airflow measurement, heating and cooling mode operational testing, and confirmation of all safety controls.
• Homeowner walkthrough: We explain how to operate your system, set schedules, use the thermostat, perform basic filter maintenance, and what to watch for between service visits.
• Rebate documentation and filing: We prepare and submit all applicable rebate applications and provide documentation for your records.

Ontario homeowners installing qualifying ducted heat pumps have access to some of the most generous home energy incentives currently available in Canada. Understanding these programs — and their requirements — before you purchase is essential, as some require steps to be completed before installation begins.

Canada Greener Homes Grant: Federal grants of up to $5,000 for homeowners who complete a pre-installation EnerGuide home energy audit and install qualifying cold-climate heat pump systems. A post-installation audit is also required to receive the full grant. Important: the pre-installation audit must be completed before work begins — you cannot work backwards. Constant Home Comfort will guide you through the sequencing.

Canada Greener Homes Loan: An interest-free loan of up to $40,000 for qualifying energy retrofits, including heat pump installations. Can be combined with the grant for maximum benefit.

Enbridge Home Efficiency Rebate Plus: Available to Enbridge Gas customers transitioning to qualifying heat pump systems from gas heating. Rebate amounts vary based on the specific system, your current heating fuel, and the current program terms at the time of application.

Municipal and local utility programs: Some Ontario municipalities and local distribution companies offer additional incentives. Our team actively monitors all available programs and will confirm every rebate available for your specific installation and location.

Rebate programs have eligibility requirements, approved equipment lists, and application deadlines. Working with a certified installer ensures your installation meets every requirement and your applications are filed correctly. At Constant Home Comfort, we manage the entire rebate process on your behalf.

A ducted heat pump that is professionally installed and regularly maintained will reliably deliver comfort for 15 to 20 years or more. Maintenance requirements are minimal compared to a gas furnace but should not be ignored:

• Replace or clean the air filter regularly: The indoor air handler uses the same filter as your previous furnace. Check it monthly and replace it every one to three months depending on filter type and household conditions. A clogged filter is the single most common cause of reduced performance and efficiency.
• Keep the outdoor unit clear: Remove leaves, debris, and snow accumulation from around the outdoor unit seasonally. Maintain at least 18 to 24 inches of clearance on all sides. In heavy snowfall, check that the unit is not buried.
• Schedule annual professional maintenance: A yearly tune-up by a certified technician — covering coil cleaning, refrigerant check, electrical inspection, filter check, airflow measurement, and full system test — extends system life, maintains efficiency, and satisfies most manufacturer warranty requirements.
• Monitor thermostat and system behaviour: If your system starts behaving differently — longer run times, unusual sounds, rooms that aren't reaching set temperatures — call for a service visit rather than waiting for a complete failure.

Constant Home Comfort offers maintenance plans that provide scheduled annual service, priority emergency dispatch, and preferred pricing on parts and repairs. Many customers enrol at the time of installation to establish a consistent service record from day one.

• Not assessing the ductwork first: Installing a high-quality heat pump on a leaky, undersized, or poorly distributed duct system is one of the most common and costly mistakes. The ductwork is as important as the equipment.
• Choosing a standard model instead of a cold-climate rated system: For Ontario winters, this is a non-negotiable. A standard heat pump will underperform in cold weather and will not qualify for most available rebates.
• Skipping the Manual J sizing calculation: Any contractor who sizes your system by square footage alone or by matching your old equipment size without a proper load calculation is taking a shortcut that will affect your comfort and efficiency for the life of the system.
• Prioritizing equipment price over total installed cost: A low equipment price paired with a rushed installation, inadequate electrical work, or no ductwork assessment is not a good deal. Ask for a fully itemized, all-in quote.
• Missing the Canada Greener Homes pre-installation audit: If you want to access the federal grant, the EnerGuide pre-installation audit must be completed before installation begins. Starting the installation before the audit forfeits the grant eligibility.
• Hiring an uncertified installer: Heat pump installation in Ontario requires licensed refrigeration mechanics and electricians. Uncertified installation voids your manufacturer warranty and can create safety and code compliance issues.
• Not planning for a dual-fuel option on marginal homes: If your home has poor insulation, significant air leakage, or unusual thermal characteristics, a dual-fuel configuration provides a reliable safety net. A proper assessment will tell you whether it's warranted.

How do I know if my home has enough insulation to use a heat pump effectively?

A heat pump works most efficiently in a well-insulated, reasonably airtight home. That said, modern cold-climate heat pumps are designed to handle homes with varying insulation levels — proper sizing accounts for your home's actual thermal characteristics rather than assuming ideal conditions. Our in-home assessment includes an evaluation of your home's envelope and will flag any areas where insulation improvements would significantly improve heat pump performance and efficiency.

Can I keep my gas furnace and add a heat pump?

Yes — this is the dual-fuel configuration described in Step 4, and it is a very popular choice among Ontario homeowners. The heat pump handles the majority of heating demand throughout the season, with the gas furnace serving as automatic backup on the coldest days. A compatible dual-fuel thermostat manages the switchover seamlessly. This approach lets you take advantage of heat pump efficiency for most of the year while retaining the peace of mind of gas backup.

How is a ducted heat pump controlled?

A ducted heat pump uses a thermostat — exactly the same way your existing furnace and air conditioner do. Most modern ducted heat pumps are compatible with smart thermostats that offer scheduling, remote access via smartphone, usage tracking, and in some cases integration with home automation platforms like Google Home or Amazon Alexa. For dual-fuel systems, a dual-fuel capable thermostat manages the switchover between heat pump and gas furnace operation automatically based on outdoor temperature.

Will a ducted heat pump work with my existing air filtration or humidity control equipment?

In most cases, yes. Your existing electronic air cleaner, HEPA filter, humidifier, heat recovery ventilator, or energy recovery ventilator can continue to operate with a ducted heat pump installed. The indoor air handler replaces your furnace but connects to the same duct system and can often accommodate the same accessories. Our technicians will review your existing equipment during the consultation and confirm compatibility or flag any required modifications.

What happens to my existing gas line if I install a heat pump only system?

If you are installing a heat pump as a full replacement for your gas furnace with no gas backup, the existing gas line to the furnace location will be capped or disconnected by a licensed gas technician. Some homeowners choose to retain the gas supply to the home for other appliances such as a gas range, gas dryer, or gas fireplace — your Constant Home Comfort technician will coordinate with a licensed gas fitter as needed to handle the disconnection properly and to code.

What warranty should I expect on a ducted heat pump?

Most major brands offer a 5-year parts warranty and a 10-year compressor warranty on registered equipment. Some brands and models offer extended coverage of up to 12 years on all major components when the system is registered promptly after installation. Always register your system — warranty registration is typically required within 60 to 90 days of installation and must be completed to activate extended coverage. Constant Home Comfort provides full warranty registration support as part of every installation.

The most important thing you can do right now is get a professional in-home assessment from a certified contractor. There is no substitute for a technician who has seen your home, measured your ductwork, assessed your insulation and air sealing, and calculated the correct system size for your specific property.

At Constant Home Comfort, our free in-home consultations are thorough, honest, and pressure-free. We carry Ontario's best selection of ducted heat pumps from Lennox, Daikin, Bosch, and American Standard — and we'll help you find the right system, at the right price, with every available rebate working in your favour.

Call us: 1 (888) 675-5907

Visit: constanthomecomfort.com

Serving Toronto, GTA, Hamilton, Ottawa, London, Barrie, Waterloo, Burlington, and all of Ontario.