Choosing the right air exchanger starts with a clear understanding of both options
When it comes to improving indoor air quality in a house or building in Montreal, Laval, Longueuil, or anywhere on the North Shore or South Shore, one question always comes up: should you choose a centralized or decentralized air exchanger? At AirGreen, specialists in HVAC systems across Greater Montreal, we guide our clients through this decision based on the building’s layout, specific ventilation needs, and goals in terms of comfort and energy efficiency.
In this article, we’ll break down the advantages, disadvantages, technical features, and real-world installation examples of both types of systems, giving you a clear, practical, field-tested comparison based on our hands-on experience with residential and commercial air exchanger installations.
Understanding how both types of air exchangers work
What is a centralized air exchanger?
A centralized air exchanger is directly connected to the building’s ductwork system, often integrated with a central heating system or a central heat pump. It allows for even distribution of fresh air and efficient extraction of stale air throughout the entire property.
Key characteristics:
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Installed in the basement, mechanical room, or a technical space.
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Requires an existing duct network or the installation of one.
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Ideal for single-family homes, multiplexes, and larger buildings.
What is a decentralized air exchanger?
On the other hand, a decentralized air exchanger works independently in one or more specific rooms. It is mounted directly through an exterior wall and does not require any ductwork.
Key characteristics:
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Wall-mounted unit installed room by room.
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Ideal for renovations or homes without existing ductwork.
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Fast and minimally invasive installation.
Comparing advantages: centralized vs. decentralized
Strengths of the centralized air exchanger
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Even distribution of air in every room.
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Centralized ventilation control.
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Compatible with existing HVAC systems.
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Aesthetic: no visible units inside rooms.
Limitations to consider
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More expensive installation, especially without existing ductwork.
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Longer, more invasive work.
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Less suitable for small living spaces.
Advantages of the decentralized exchanger
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Quick installation, often within a single day.
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No need for a ductwork network.
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Ideal for renovation projects or older homes.
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Modular solution: units can be added over time.
Drawbacks not to overlook
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Less effective in large or multi-story homes.
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Independent control for each unit: less convenient in some cases.
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Visible wall-mounted units in each room.
Key selection criteria to consider
Building size and layout
For a 3-story multiplex in Laval with existing ventilation ducts, we recently installed a centralized VENMAR AVS N Series air exchanger, which provided balanced air treatment across all units. On the other hand, for an older apartment in Longueuil, without ceiling access or a technical basement, we installed two Zehnder ComfoAir 70 decentralized units, offering a practical and efficient solution without major renovations.
Level of insulation and air tightness
The more airtight a building is, the more essential mechanical air renewal becomes. In these cases, a centralized heat recovery air exchanger (HRV) is generally recommended to avoid humidity issues and stagnant air.
Budget and technical constraints
A homeowner in Montreal recently hesitated between centralized and decentralized options. After our assessment, we found that a centralized system would have required major construction due to the building’s structure. Instead, we recommended a series of Blauberg VENTO Expert A50-1 decentralized air exchangers, providing a fast, cost-effective solution that met energy code requirements.
Government grants and energy efficiency
It’s worth noting that some heat recovery air exchangers are eligible for government rebates under Hydro-Québec’s LogisVert program. These grants are available on the South Shore and in several boroughs of Montreal, and can significantly reduce the cost of a centralized system.
At AirGreen, we assist our clients in preparing all documentation for rebate applications, ensuring the selected equipment is Energy Star certified or equivalent, with heat recovery efficiency over 65%.
Real installation stories
Project in Sainte-Thérèse (North Shore)
In an intergenerational home, we installed a central Fantech VHR150R air exchanger combined with a central Goodman heat pump. The result: perfectly balanced ventilation in both living spaces, without heat loss.
Project in Brossard (South Shore)
In a 5½-room condo without space for ductwork, our team installed three Vents TwinFresh Comfo RA1-50 decentralized air exchangers, ensuring silent cross ventilation, with heat recovery during the winter.
Our professional tips for making the right choice
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Always have your true needs assessed by an HVAC expert before making a decision.
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Consider your building’s structural constraints.
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Don’t forget about future maintenance: a centralized system requires periodic duct cleaning, while a decentralized system involves maintenance for each unit individually.
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Always request an energy assessment, especially if you want to qualify for a grant.
Why trust AirGreen?
AirGreen brings over 15 years of experience in custom HVAC installations, whether in Montreal, Laval, Longueuil, on the North Shore, or the South Shore. Our expertise allows us to recommend the best ventilation solution for your reality, with no compromise on comfort, efficiency, or durability. Our team handles everything: from technical evaluation to professional installation, and even the submission of rebate applications.
Final word: centralized or decentralized, the key is adaptation
The right choice between a centralized or decentralized air exchanger depends above all on your building, your budget, and your goals in terms of air quality and energy efficiency. At AirGreen, we’re here to guide you with objectivity, expertise, and commitment. Contact us today for a free assessment of your situation.