A technical HVAC project in Duvernay, designed to optimize space, performance, and reliability
In Duvernay, a well-established residential and commercial area of Laval, our AirGreen team completed a HVAC installation that perfectly illustrates the demands of a modern project: integrating a GREE Mini-GMV VRF system that is efficient, discreet, and durable, while respecting the constraints of an existing building, a flat roof, and a dense urban environment. The photo of this project clearly shows the outdoor unit installed on a sturdy treated wood base, placed on a protective membrane, with open access to the technical compartment for commissioning checks.
This type of project requires much more than just equipment installation. A VRF system demands rigorous planning: load calculations, validation of piping lengths, choice of outdoor location, condensation management, electrical connections, pressurization, vacuuming, programming, and multi-zone operation verification. In this particular case, rooftop installation was the most logical solution to preserve ground space, reduce visual impact, and facilitate refrigerant distribution to indoor zones.
The client was looking for a solution capable of managing multiple spaces precisely, without multiplying outdoor units. The choice of the GREE Mini-GMV was obvious for its ability to supply multiple indoor units, its stability in heating during cold weather, and its design suited for high-end residential projects, light multi-unit buildings, and small commercial buildings in Montreal, Laval, Longueuil, on the North Shore and the South Shore.
Why a GREE Mini-GMV VRF system for this building in Duvernay
A VRF, or variable refrigerant flow system, allows precise adjustment of the amount of refrigerant sent to each indoor zone according to actual demand. Unlike a simpler solution that often operates more uniformly, the GREE Mini-GMV modulates its operation to maintain a more constant temperature, zone by zone.
In this installation in Duvernay, this approach was particularly important. Flat-roof buildings in Laval often face very concrete constraints: limited mechanical space available, need to reduce noise near neighboring windows, sometimes complex duct or refrigerant line routes, and the obligation to work cleanly without compromising the roof’s waterproofing.
The chosen system notably allows:
- multi-zone management with a single outdoor unit;
- better thermal stability in the served rooms;
- a reduction in outdoor footprint;
- performance adapted to Quebec winters, with heating down to about -30 °C depending on eligible GREE configurations;
- a professional approach compatible with projects where comfort, silence, and aesthetics matter as much as performance.
In the AirGreen catalog, GREE Mini-GMV systems are available in 36,000 BTU and 48,000 BTU configurations, with different zone combinations depending on the building’s needs. For each project, we validate the exact capacity not only based on area but also on insulation, solar orientation, ceiling height, room usage, internal gains, and the actual layout of the building.
A rooftop installation: the right location, but not the easiest
The installation shown in the photo was done on a flat roof, a common choice in some areas of Laval and Montreal, but it requires very methodical execution. Installing an outdoor VRF unit on a roof is never just about placing the machine and plugging it in. Equipment stability must be ensured, the membrane protected, service access planned, air clearances respected, and vibration transmission to the building limited.
Our team first prepared a solid base, made up of beams installed to distribute the unit's weight over the available surface. Protective membranes were placed under the support points to prevent any damage to the roof. This step is essential: a poor base can create pressure points, hinder drainage, or complicate future maintenance.
The outdoor unit GREE Mini-GMV was then carefully positioned to ensure:
- sufficient clearance in front of the fans;
- side access to the electrical and refrigerant compartment;
- adequate airflow around the exchanger;
- an orientation allowing future interventions without unnecessary disassembly;
- a clean integration with refrigerant lines, electrical supply, and mechanical supports.
The photo also shows the service panel open, which corresponds to a critical step in our process: checking connections, electronic boards, pressures, fittings, and the startup sequence. In a VRF system, this step is essential because a wiring error, an improperly validated length, or incomplete programming can affect multiple zones at once.
Technical challenges encountered during this HVAC installation
This project in Duvernay involved several typical challenges of advanced HVAC installations.
Roof access and safe handling
An outdoor VRF unit of this size is bulky. Moving it to the roof requires coordination, suitable equipment, and a team experienced with this type of handling. We planned access considering technician safety, building protection, and equipment stability throughout all stages.
Roof membrane protection
On a flat roof, the membrane is a critical element. Poorly installed support, a tool left in the wrong place, or repeated vibration can cause long-term problems. That’s why we always work with appropriate protections under the bases and maintain strict organization of the work area.
Refrigerant line management
A GREE Mini-GMV system can serve multiple indoor zones. This means that the refrigerant lines must be precisely planned: lengths, elevation changes, insulation, routing, bend radii, external protection, and access for maintenance. For this project, the goal was to maintain a clean and efficient path without unnecessarily exposing the lines to mechanical risks or thermal losses.
Specialized commissioning
Commissioning a GREE VRF requires a more advanced approach than a standard wall-mounted installation. We specifically carry out pressure testing, leak testing, vacuum pulling, verification of electrical connections, validation of communication between components, and then system programming. This rigor ensures a stable and reliable installation from the start.
A GREE Mini-GMV solution designed for multi-zone comfort in Laval and Greater Montreal
The client wanted a solution that does not just heat and cool but offers smarter comfort management. In a building with multiple spaces, needs often vary from one zone to another. A sun-exposed room does not have the same needs as a space located to the north. An office occupied all day does not behave like a bedroom or a room used only at certain times.
The GREE Mini-GMV VRF system precisely meets this reality. It adjusts its operation according to actual demand, which improves comfort while avoiding abrupt cycles. This modulation also helps reduce mechanical wear when the installation is properly sized and configured.
Concrete advantages for the client
At the end of the installation, the client benefits from a solution better integrated into their building, with a single outdoor unit installed outside the living area. Floor space is preserved, the exterior appearance is more discreet, and future maintenance remains accessible thanks to the chosen location.
The most important benefits are:
- personalized comfort in each served zone;
- reduction in the number of visible outdoor units;
- modulating operation, more stable than an all-or-nothing system;
- better management of temperature variations between rooms;
- solution suited for advanced residential and light commercial projects;
- professional installation designed for long-term maintenance.
For an owner in Duvernay, this type of system represents a serious investment but is consistent when the building requires multiple comfort zones and a clean outdoor installation.
GREE Mini-GMV: a platform suited for complex projects
The GREE Mini-GMV systems distributed by AirGreen are designed for projects where a simple wall-mounted heat pump is not enough. Depending on the chosen configuration, they can power multiple indoor units and offer cooling capacities of 36,000 BTU or 48,000 BTU. Common combinations can serve two, three, four, five, six, or even seven zones depending on the platform selected and the actual needs of the building.
The range is particularly interesting for:
- houses with multiple floors;
- condos requiring a compact solution;
- small rental buildings;
- professional offices;
- neighborhood shops;
- spaces where the exterior aesthetics must remain controlled;
- projects where the comfort of each zone must be adjustable.
At AirGreen, we never recommend a VRF just because it is advanced equipment. We recommend it when it truly fits the building. In some cases, a simple wall-mounted heat pump is sufficient. In others, a standard multi-zone system works very well. But when distances, thermal loads, multiple zones, and comfort management become more complex, the VRF GREE Mini-GMV becomes a very relevant solution.
The role of our team in the success of the project
An installation like this relies on precise coordination between estimation, design, logistics, and execution. Before installation, we analyzed the building constraints and validated the location of the outdoor unit. During the work, our technicians organized the roof to keep a clean and safe area, with tools, hoses, and measuring instruments arranged to facilitate commissioning.
The site image clearly reflects this stage: the unit is in place, the service panels are open, the instruments are connected, and checks are underway. It is often at this moment that the difference between an ordinary installation and a professional HVAC installation becomes visible. Details matter: tightening connections, unit support, cable protection, line insulation, drainage, clearances, cleanliness of the path, and commissioning documentation.
Our clients in Montreal, Laval, Longueuil, on the North Shore and the South Shore appreciate this approach because it reduces unexpected issues and makes after-sales service easier. A well-thought-out installation today makes future interventions faster, cleaner, and less expensive.
Mistakes to avoid during a VRF installation
A VRF system offers very good performance when well designed, but it tolerates little approximation. Here are the most common mistakes we systematically avoid on this type of project.
Choosing capacity based only on surface area
The surface area gives a first idea, but it is not enough. A highly glazed, poorly insulated, or strongly sun-exposed building may require a different approach than a more compact and well-insulated building. We always prioritize a calculation adapted to real conditions.
Neglecting piping lengths
In a multi-zone system, lengths and height differences directly affect performance. Poorly planned piping can cause losses, malfunctions, or premature wear.
Installing the unit without considering maintenance
An outdoor unit must remain accessible. On a roof, you have to think about the technician who will need to intervene in a few years: access to the service panel, space for tools, clearance around the machine, and base stability.
Forgetting roof protection
A good installation should never compromise the building envelope. Protecting the membrane and distributing weight are priorities from the start.
Entrusting a VRF to a non-specialized team
The VRF is not a basic installation. It requires understanding of refrigeration networks, communication between units, programming, and commissioning procedures. At AirGreen, our teams are trained for these systems and work according to a structured method.
Grants, warranty, and support
Depending on the type of project, the chosen configuration, the building's use, and current criteria, some financial aids may be available. Grant programs evolve, and eligibility depends on the exact model, capacity, application, and administrative requirements. AirGreen supports its clients in understanding the possible options and provides clear documentation when the project is eligible.
The warranty is also an important element. As an experienced dealer of GREE solutions, AirGreen emphasizes compliant installation, because a solid warranty always relies on professional implementation. The selected GREE models can offer up to 12 years of warranty under applicable conditions, which is a significant advantage for owners who want to invest in a durable solution.
A representative achievement of our expertise in Duvernay
This installation of a GREE Mini-GMV VRF system in Duvernay demonstrates what we look for in every project: a well-chosen solution, clean execution, thoughtful mechanical integration, and serious commissioning. The result is not just a well-installed outdoor unit on a roof. It is a complete system that must provide comfort, reliability, and great flexibility of use for many years.
For AirGreen, this type of project reflects our specialization in HVAC projects that require more than a standard installation. We regularly work in complex contexts: flat roofs in Laval, downtown Montreal condos, multi-zone houses on the North Shore, commercial spaces on the South Shore, residential buildings in Longueuil. Each building has its constraints, but our method remains the same: analyze, plan, install cleanly, and validate performance.
Why choose AirGreen for a VRF project in Laval
A VRF project requires a company capable of managing the technical aspect, site coordination, and after-sales service. AirGreen offers this continuity. From the estimate, we present options adapted to the building. Before the work, we clarify the installation process. During execution, our technicians work rigorously. After commissioning, we remain available for maintenance, adjustments, and client questions.
Our approach is based on simple but essential elements:
- clear estimates;
- recommendations tailored to the building;
- experienced refrigeration technicians;
- clean and compliant installations;
- liability insurance of 5 000 000 $;
- post-installation support;
- local expertise in Montreal, Laval, Longueuil, on the North Shore and the South Shore.
This project in Duvernay confirms that an advanced system like the GREE Mini-GMV can be integrated cleanly, safely, and efficiently when entrusted to a team that understands the details of the site.