Installation of a Daikin central heat pump on a flat roof in Saint-Laurent
AirGreen installed a Daikin central heat pump on a flat roof in Saint-Laurent. A reliable and energy-efficient HVAC solution for commercial buildings in Greater Montreal.
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.
It captures or rejects heat outside. It sits on a level base, above the snow, with free space all around.
The insulated refrigerant lines enter the house through a sealed opening and run to the indoor coil.
A shut-off switch near the outdoor unit isolates it safely for service.
Sitting on the indoor module, it moves heat between the house air and the refrigerant.
Electric furnace or air handler: its fan pushes air through the ducts. The electric backup takes over in extreme cold.
Supply ducts bring air to the rooms; returns bring it back to the unit. Their condition matters as much as the unit's.
It protects the coil and the fan. A dirty filter cuts airflow, so it gets checked regularly.
It runs the heat pump and the backup heat. It must be compatible with the installed system.
A high-performance and sustainable solution for a commercial building
At AirGreen , we recently completed an HVAC installation in the Saint-Laurent area of Montreal. The project involved installing a Daikin central heat pump on the flat roof of a commercial building, a solution perfectly suited to the heating and cooling needs of professional spaces.
This type of installation presents technical and logistical specificities that require specialized expertise. The goal was to ensure optimal operation throughout the year, including during the harsh winters of Greater Montreal.
Why choose a Daikin central heat pump for a commercial building?
The Daikin brand is recognized worldwide for its reliable, efficient equipment designed for the North American climate . Installing a Daikin unit on a flat roof offers several advantages:
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High energy performance , reducing annual operating costs.
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Heating/air conditioning versatility , capable of maintaining indoor comfort in summer and winter.
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Adaptability to large spaces , ideal for offices, shops and multi-tenant buildings.
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Durability : Designed to withstand Montreal's extreme weather conditions, including snow, ice and heavy rain.
Key steps of installation
Our specialized technicians have proceeded methodically to guarantee the performance and safety of the installation:
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Roof preparation : a clear and stable space was chosen to accommodate the outdoor units.
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Raised supports : the heat pumps were fixed on treated wooden rails and metal bases to ensure good stability and avoid any direct contact with the roof gravel.
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Refrigeration and electrical connections : the connections have been carefully insulated and protected to ensure maximum longevity. The electrical cables have been routed to a dedicated junction box (labeled 408 ), ensuring safety and compliance.
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Weather protection : Insulating hoods and sheaths were installed to protect the piping from cold and humidity.
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Commissioning and testing : after connection, comprehensive testing ensured the heat pump was operating correctly in heating and air conditioning modes.
Technical challenges and solutions
A flat roof installation is never trivial. In this project, two major constraints arose:
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Condensate drainage management : On a flat roof, it is essential to prevent any water accumulation. We have provided efficient drainage to ensure that condensate drains properly, even in freezing weather.
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Distance between the units and the electrical panel : the cable run required precise planning in order to reduce electrical losses and ensure an installation that complies with current standards.
Thanks to our expertise, these challenges were successfully met, guaranteeing a high-performance and safe installation.
A profitable and energy-efficient investment
Opting for a Daikin central heat pump not only reduces your energy bill, but also allows you to take advantage of grants available in Quebec for energy-efficient systems. These financial aids can cover part of the costs, making this type of project even more advantageous for property managers and commercial owners.
AirGreen expertise serving Greater Montreal businesses
At AirGreen, we understand that every building has its own unique characteristics. Our role is to design and install HVAC systems that meet technical requirements while providing comfort, reliability, and energy savings.
Whether in Montreal, Laval, Longueuil, on the North Shore or the South Shore , our teams are available to support owners and managers in their central heat pump installation projects.
Conclusion: a successful turnkey installation
This project in Saint-Laurent perfectly illustrates our ability to carry out complex installations on flat roofs, while guaranteeing the quality and reliability of the equipment chosen. The installed Daikin central heat pump will provide comfort and energy savings to the building's occupants for many years to come.
At AirGreen, every installation is proof of our commitment to providing the best in heating, ventilation and air conditioning in Greater Montreal.
How it goes, from the first call to the end
The main steps of this kind of job at AirGreen. Every house has its quirks: the estimate brings them out.
We look at the ducts, the current indoor module, the electrical panel and the planned spot for the outdoor unit.
The equipment combination, capacity and price, in writing. We check whether the combination qualifies for assistance programs.
Access protected, old unit disconnected and removed when it is being replaced.
Electric furnace or air handler, with its coil, connected to the supply and return ducts.
On a level base, raised above the snow, with free space all around.
Insulated, they enter through a sealed opening and run to the indoor coil.
Dedicated circuits, accessible disconnect, a thermostat that works with the heat pump and the backup heat.
Leak test, vacuum, start-up, airflow check and a test of both modes.
Filter, thermostat, backup heat in extreme cold: what to know before winter.
- The on-site estimateWe look at the ducts, the current indoor module, the electrical panel and the planned spot for the outdoor unit.
- The quoteThe equipment combination, capacity and price, in writing. We check whether the combination qualifies for assistance programs.
- Getting readyAccess protected, old unit disconnected and removed when it is being replaced.
- The indoor moduleElectric furnace or air handler, with its coil, connected to the supply and return ducts.
- The outdoor unitOn a level base, raised above the snow, with free space all around.
- The refrigerant linesInsulated, they enter through a sealed opening and run to the indoor coil.
- Electrical and thermostatDedicated circuits, accessible disconnect, a thermostat that works with the heat pump and the backup heat.
- Tests and start-upLeak test, vacuum, start-up, airflow check and a test of both modes.
- The walkthroughFilter, thermostat, backup heat in extreme cold: what to know before winter.
And at your place?
Two quick checks with real numbers: what heat costs, and what your current heaters add up to in BTU/h.
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.
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.
- Check the filter more often in peak season.
- Keep registers and returns clear.
- Watch condensate drainage near the coil.
- Change or clean the filter.
- Test heating and backup heat before the cold.
- Book periodic maintenance.
- Clear snow around the outdoor unit.
- Store nothing in front of the indoor module.
- Note any unusual noise or smell and call us.
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What people ask us about this kind of work
Can I keep my current ducts?
What happens in extreme cold?
Furnace, air handler, ducted: what is the difference?
Are there grants?
Do I need a permit?
How much can I save?
How is the LogisVert assistance calculated?
Will my current thermostat work?
Central or wall units: which one?
Does AirGreen hold the required licences?
Is the estimate free?
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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).