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Installation of a GREE Slim Duct ducted system in Montreal: a discreet HVAC solution integrated into a compact technical space

AirGreen installs a GREE Slim Duct ducted heat pump in Montreal: discreet comfort, integrated ducts, precise work in compact technical spaces, and residential HVAC expertise.

By AirGreen Climatisation & Chauffage Admin13 min read
Installation of a GREE Slim Duct ducted system in Montreal: a discreet HVAC solution integrated into a compact technical space
Installation of a GREE Slim Duct ducted system in Montreal: a discreet HVAC solution integrated into a compact technical space
–chapters in this story
13 minreading time
–type of installation
2026year published
The tour

Take a tour of the installation

Each number is a point we check on site. Switch between summer and winter to watch air and heat move.

Generic diagram: central heat pump, indoor module and ducts

In summer, the outdoor unit rejects the house's heat outside.

Generic illustration of this type of installation, not a survey of this job site. Tap a number.

  1. It captures or rejects heat outside. It sits on a level base, above the snow, with free space all around.

  2. The insulated refrigerant lines enter the house through a sealed opening and run to the indoor coil.

  3. A shut-off switch near the outdoor unit isolates it safely for service.

  4. Sitting on the indoor module, it moves heat between the house air and the refrigerant.

  5. Electric furnace or air handler: its fan pushes air through the ducts. The electric backup takes over in extreme cold.

  6. Supply ducts bring air to the rooms; returns bring it back to the unit. Their condition matters as much as the unit's.

  7. It protects the coil and the fan. A dirty filter cuts airflow, so it gets checked regularly.

  8. It runs the heat pump and the backup heat. It must be compatible with the installed system.

The job

Centralized comfort without visible wall units: The challenge of a well-designed ducted installation

In many residences in Montreal, particularly renovated homes, plexes, multi-level condos, and properties where interior aesthetics are as important as performance, installing a GREE ducted heat pump is a very attractive solution. Unlike a visible wall-mounted unit, a ducted system, also called ducted air conditioning, Slim Duct, or ductable, distributes conditioned and heated air through discreet ducts, often integrated into a ceiling, false ceiling, attic, or existing technical space.

During this installation in Montreal, our AirGreen team had to work in a confined area where the equipment needed to be neatly integrated without compromising service access, air circulation, insulation, or the final quality of the distribution network. The project photo clearly shows the context: a GREE unit installed in a technical cavity, with connection and framing work that demands precision, method, and field experience. This type of installation is not limited to "installing a machine": it requires designing a complete, balanced, durable, and easily accessible system for HVAC maintenance.

The client wanted to achieve more uniform comfort in their living space without multiplying visible wall units. The objective was clear: maintain a clean interior finish, reduce the visual impact of air conditioning, improve air distribution, and choose a brand known for its reliability. The choice fell on a GREE ducted system, a relevant option for residential projects where efficiency, discretion, and installation flexibility are desired.

Why a GREE ducted system rather than a classic wall unit

In a traditional residential project, the simplest solution is often the wall-mounted air conditioner or the wall-mounted heat pump. These units are efficient, quick to install, and suitable for many open spaces. However, in certain buildings in Montreal, especially when interior divisions are more complex or when the owner desires a more discreet finish, a ducted system becomes significantly more appropriate.

With a GREE ducted heat pump, the indoor unit is hidden in a technical area. Air is then distributed through ducts to one or more grilles. The result is more architectural: typically, only the supply and return grilles are visible, which helps maintain a clean interior design.

In this project, the main advantage was the ability to integrate the equipment without heavily altering the appearance of the main rooms. The client did not want a wall unit to become a dominant element in their decor. The GREE Slim Duct system precisely met this constraint, while allowing for better distributed air diffusion.

Installation in a confined space: Precision, access, and air circulation

The construction site image reveals a common reality in ducted installations: the available space is rarely ideal. Here, the unit had to be positioned in a narrow technical section, close to structural elements, insulation, wiring, and already finished surfaces. This kind of environment requires several checks even before work begins.

Our technicians first validated:

  • the necessary clearance around the unit to ensure good access to the motor, fan, and internal components;
  • the possibility of connecting ducts without creating excessive pressure drops;
  • the orientation of the supply and return air;
  • the stability of the support;
  • the clearance required for future service interventions;
  • the insulation of exposed sections to limit thermal losses and condensation;
  • the routing of drainage;
  • compatibility with the planned location of the outdoor unit.

In a ducted system, every detail influences performance. A poor duct transition, an undersized grille, or a poorly placed return air vent can lead to noise, reduced airflow, or uneven comfort. This is why AirGreen pays particular attention to sizing and balancing, especially in installations in Montreal, Laval, Longueuil, on the North Shore and the South Shore, where buildings often have very different configurations from one project to another.

The role of the ductwork in actual performance

A ducted system never performs alone. Its quality depends as much on the machine as on the ductwork. For this GREE installation, our work was not limited to integrating the indoor unit: we had to ensure that air could circulate efficiently, without unnecessary restriction.

A too-narrow duct increases static pressure. A poor junction can generate turbulence. A poorly insulated section can create condensation in cooling mode or heat loss in heating mode. A poorly positioned grille can blow air directly into an uncomfortable zone or leave certain rooms less well-tempered.

At AirGreen, we therefore approach ducted air conditioning systems as complete HVAC installations. We analyze the air path, lengths, bends, available pressure, room-by-room needs, and ease of maintenance. This approach is particularly important with GREE models, which are available in several configurations, including low static pressure, high static pressure, and the All Match Slim Duct R32 series.

GREE Ducted: A range suitable for residential and multi-zone projects

The GREE ducted range offered by AirGreen includes several capacities and configurations to meet different types of projects. On our website, customers can find GREE solutions in 9,000 BTU, 12,000 BTU, 18,000 BTU, 21,000 BTU, 24,000 BTU, 30,000 BTU and 36,000 BTU, depending on the series and intended application.

For a compact dwelling or a targeted zone, a capacity of 9,000 or 12,000 BTUs may be sufficient. For a larger floor, an open-concept area, or a project where several rooms need to be served, a higher capacity can be considered. The choice should never be based solely on surface area. Insulation, solar orientation, number of occupants, windows, ceiling height, existing structure, and duct length must also be taken into account.

In the case of this installation in Montreal, the priority was to obtain a discreet and well-integrated solution, with stable distribution. The choice of a GREE ducted system made it possible to meet this requirement while maintaining an interesting design margin for duct layout.

Low Static Pressure or High Static Pressure: An Important Technical Decision

In the GREE range, there are ducted models with low static pressure and high static pressure. This distinction is essential. A low static pressure model is generally suitable for short, simple networks with few bends and few grilles. A high static pressure model is more suitable when air needs to be pushed through a longer or more complex network.

For a client, this difference might seem very technical. In practice, it changes everything. Installing a low static pressure unit on an overly demanding network can reduce airflow and negatively impact comfort. Conversely, choosing a high static pressure unit for a very short network without proper adjustment can create a higher noise level than necessary.

During our free estimates, we evaluate these elements before recommending a solution. This is one of the reasons why AirGreen avoids generic recommendations. Two houses of the same size in Montreal may require two completely different configurations.

Clean integration despite site constraints

The project presented here illustrates an important reality: a ducted installation often requires on-site adaptation. Openings must be adjusted, ducts must be carefully connected, insulation must be properly sealed, and access points must remain usable. Our team had to work with an existing wooden structure, a partially insulated environment, and limited clearance around the unit.

The success of the installation therefore depended on several precise actions:

  • positioning the unit in a stable and accessible manner;
  • protecting connections against air leaks;
  • maintaining sufficient passage for return air;
  • avoiding excessive compression of the insulation;
  • providing a functional finish around the module;
  • securing electrical connections;
  • checking drainage and condensation evacuation;
  • testing full operation before finalizing the site.

This type of project clearly shows the difference between a standard installation and a professional HVAC installation. The invisible work behind the walls or in the ceilings directly influences the comfort experienced by the client for years to come.

AirGreen Tips for a Successful Ducted Heat Pump Installation in Montreal

Do not underestimate the importance of sizing

One of the most frequent errors is to choose a BTU capacity based solely on a quick estimate of the area. This method can lead to a unit that is too large or too small. An oversized unit can operate in short cycles, reduce dehumidification, and cause temperature variations. An undersized unit can run too long without achieving the desired comfort, especially during periods of intense heat or sustained cold.

For a GREE ducted system, sizing must be even more precise, as the duct network must also be considered. The unit's capacity and available static pressure must match the actual system design.

Plan for service access from the outset

A ducted system is often hidden. This is excellent for aesthetics, but it can become problematic if access to the filter, motor, drain, or connections is not properly planned. In this installation in Montreal, our team paid particular attention to future accessibility. A good system must be maintainable without unnecessary demolition.

We always recommend planning for a clear access hatch or service area. Regular HVAC maintenance is essential to preserve airflow, reduce noise risks, maintain energy performance, and extend the equipment's lifespan.

Careful condensation drainage

In cooling mode, the indoor unit removes humidity from the air. This condensation must be properly evacuated. In a ducted system installed in a ceiling, attic, or enclosed space, improper slope or a poorly designed drain can cause damage. This is why our technicians carefully check the drain routing and the risks of backflow.

Depending on the configuration, a condensate pump may be necessary. However, when gravity drainage is possible and reliable, it is often preferable. Each site must be evaluated individually.

Choosing the right supply and return grilles

The quality of comfort also depends on the grilles. A grille that is too small can create noise. A poorly placed grille can direct air to an unwanted area. An undersized return grille can limit airflow and strain the fan.

In ducted projects, we analyze the location of the grilles based on the use of the rooms. A bedroom, living room, office, or hallway are not treated in the same way. The goal is to create uniform comfort, without unpleasant drafts.

Properly insulate ducts and connections

Insulation is a major aspect, especially when ducts pass through an unconditioned or partially insulated space. Poor insulation can lead to performance losses, condensation, or temperature variations. On this project, the visible technical context around the installation required particular attention to sealing and surface protection.

A well-insulated network helps preserve the system's efficiency and deliver air at the right temperature to the served rooms.

Why choose AirGreen for a GREE ducted installation

AirGreen regularly works on residential and commercial projects in Montreal, Laval, Longueuil, on the North Shore and the South Shore. Our experience with heat pump systems, wall-mounted air conditioners, central units, multi-zones, and ducted systems allows us to adapt each project to the building's reality.

For GREE systems, our role is not limited to selling equipment. We guide the client through model selection, space analysis, network design, installation, commissioning, usage explanations, and after-sales service. This comprehensive approach is essential for integrated systems, where the quality of the result depends as much on the design as on the appliance.

We also place great importance on transparency. Before starting work, we detail the included elements, possible constraints, and potential extras, for example, for additional piping lengths, special ducts, a condensate pump, difficult access, or attic work.

A relevant choice for owners who want a discreet result

The GREE Slim Duct system installed in Montreal meets an increasingly common demand: achieving effective comfort without visible appliances in main rooms. For homeowners renovating, wanting to preserve architectural finishes, or wishing to discreetly air-condition multiple zones, ducted systems are a very serious option.

However, it is important to remember that this type of installation requires more planning than a wall-mounted unit. The duct network, grilles, service access, insulation, static pressure, and drainage must be designed correctly. This is precisely where the experience of a specialized HVAC contractor becomes crucial.

Final Result: A Functional, Discreet Installation, Ready for Everyday Use

At the end of this installation, the client obtained an integrated solution that met the initial objective: improving indoor comfort while keeping appliances out of sight in living areas. The GREE unit was integrated into a compact technical space, with particular attention paid to airflow, connection, accessibility, and system reliability.

This project demonstrates that a successful HVAC installation relies on a combination of technical choices, practical experience, and meticulous finishing. For a GREE ducted system in Montreal, every detail counts: the machine, ducts, return air, clearances, drainage, and commissioning.

At AirGreen, we consider these projects to be custom installations. This allows us to offer lasting comfort, clean integration, and performance adapted to the actual needs of the building.

The steps

The big day, step by step

The main steps of this kind of job at AirGreen. Every house has its quirks: the estimate brings them out.

Step 1 of 9The on-site estimate

We look at the ducts, the current indoor module, the electrical panel and the planned spot for the outdoor unit.

  1. The on-site estimateWe look at the ducts, the current indoor module, the electrical panel and the planned spot for the outdoor unit.
  2. The quoteThe equipment combination, capacity and price, in writing. We check whether the combination qualifies for assistance programs.
  3. Getting readyAccess protected, old unit disconnected and removed when it is being replaced.
  4. The indoor moduleElectric furnace or air handler, with its coil, connected to the supply and return ducts.
  5. The outdoor unitOn a level base, raised above the snow, with free space all around.
  6. The refrigerant linesInsulated, they enter through a sealed opening and run to the indoor coil.
  7. Electrical and thermostatDedicated circuits, accessible disconnect, a thermostat that works with the heat pump and the backup heat.
  8. Tests and start-upLeak test, vacuum, start-up, airflow check and a test of both modes.
  9. The walkthroughFilter, thermostat, backup heat in extreme cold: what to know before winter.
Your numbers

What would it look like at your place?

Two quick checks with real numbers: what heat costs, and what your current heaters add up to in BTU/h.

Size checkYour electric furnace, in BTU/h
–BTU/h of installed electric heat

    Conversion: 1 W = 3.412 BTU/h. An indication, not a load calculation: baseboards and furnaces are often stronger than the real need, and they can stay as backup. AirGreen confirms the capacity on site.

    Mistakes avoided

    Four mistakes we do not make

    Flip each card to see what we do instead.

    Going further

    Your own project, step by step

    Through the seasons

    What to do, season by season

    Three habits per season for this unit. They take a few minutes and prevent many calls.

    • Check the indoor module's filter.
    • Clear winter debris from the outdoor unit.
    • Test cooling before the heat arrives.
    At your place

    Is your home ready?

    Check what applies at your place. A "no" is not a refusal: it is what we sort out during the estimate.

    0 / 6 checked
    True or false

    Four statements: true or false?

    It all comes down to details you have just seen.

    1. A central heat pump uses the house's ducts.

    2. In extreme cold, electric backup heat can take over.

    3. The filter only gets changed when the unit breaks down.

    4. You can reuse the old unit's size without checking.

    Frequently asked questions

    What people ask us about this kind of work

    11 questions
    Can I keep my current ducts?
    Often, yes: the central heat pump connects to the existing ducts. We check their condition and size during the estimate.
    What happens in extreme cold?
    The indoor module (furnace or air handler) works with the central heat pump and takes over in extreme cold.
    Furnace, air handler, ducted: what is the difference?
    The furnace or air handler is the indoor module of the central system. A ducted system hides in the ceiling: all you see are small supply grilles.
    Are there grants?
    Depending on the equipment and your situation, assistance programs may apply. AirGreen checks the exact combination before quoting an amount. See the grants.
    Do I need a permit?
    Rules vary from city to city. See permits and by-laws, and we check for your address.
    How much can I save?
    Hydro-Québec says a heat pump can be up to three times more efficient than baseboards for heating in the colder months. The result depends on the house, the climate and how it is used.
    How is the LogisVert assistance calculated?
    For ENERGY STAR cold-climate certified heat pumps, Hydro-Québec lists assistance of $120 per 1,000 BTU/h of heating capacity at −8 °C. AirGreen checks the exact model before quoting an amount; only Hydro-Québec confirms the assistance granted. See the grants.
    Will my current thermostat work?
    Not always: the thermostat has to run the heat pump and the backup heat. We check compatibility during the estimate.
    Central or wall units: which one?
    If the house has ducts in good shape, a central system heats and cools every room at once. Without ducts, wall units or a multi-zone are often simpler. We compare on site.
    Does AirGreen hold the required licences?
    Yes. AirGreen holds RBQ licence 5645-9605-01, subclasses 15.8 Ventilation, 15.10 Refrigeration and 16 Electricity.
    Is the estimate free?
    Yes. The on-site estimate is free and the quote follows within 24 hours. Book my free estimate.

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    Text and photo: a real AirGreen Climatisation & Chauffage job. The diagrams are generic illustrations of the type of installation, not a survey of this job site. Sources of the added figures: airgreen.ca product pages (NEEP / AHRI performance), Hydro-Québec (Heat pumps page, LogisVert, read on 13 October 2026), Régie de l’énergie (rate D as of 1 April 2026).

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