Installation of a Willis wall-mounted air conditioner in Outremont
AirGreen installed a Willis wall-mounted air conditioner in Outremont, ensuring comfort, aesthetics and energy performance for this heritage residence.
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.
Mounted level on a wall plate, high enough for the air to reach the whole room, with enough space around it to slide the filters out easily.
The refrigerant lines, the communication cable and the drain go through the wall in a single opening, sealed against water, cold air and insects.
Two insulated copper pipes connect the two units. Outside, a line cover can protect them from sun, knocks and weather.
A shut-off switch near the outdoor unit isolates it safely for service. It must stay accessible at all times.
The compressor and the fan. In heating mode it captures heat from the outdoor air, even in winter, and moves it inside.
On the ground or on the wall, it keeps the unit above accumulated snow. The unit stays clear and defrost water can drain away.
The fan needs to blow freely. Storage, a fence or a wall too close, and efficiency drops while noise goes up.
An elegant project in the heart of a heritage house
At AirGreen , we understand that every home presents its own unique challenges when it comes to integrating a wall-mounted air conditioning system. This project in Outremont perfectly illustrates the blend of modern comfort and traditional architecture. Our team installed a Willis wall-mounted air conditioner , carefully positioned in an entrance hall with high ceilings and arched windows typical of the neighborhood's heritage homes.
The importance of strategic positioning
The indoor unit was mounted above a large arched window, a location that required pinpoint precision to preserve the aesthetics of the decor and ensure optimal air circulation. Thanks to this elevated installation:
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Fresh air diffuses harmoniously throughout the entrance hall and adjacent rooms.
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The unit remains visually discreet, blending into the neutral shade of the walls.
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The system operates by gravity for condensate drainage, avoiding the need for a pump and reducing future maintenance.
Features of the Willis wall-mounted air conditioner
The choice of the Willis wall-mounted air conditioner met the customer's specific needs:
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12,000 BTU capacity suitable for the open space of the entryway and living room.
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Inverter technology for precise temperature control and reduced energy consumption.
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Quiet operation , essential in a home where acoustic comfort is as important as thermal comfort.
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Eligibility for grants available in the greater Montreal area for energy-efficient appliances.
Challenges and solutions provided by AirGreen
Working height
Installing a wall-mounted air conditioner in a stairwell or hall with high ceilings requires planning and the right tools. Our technicians used compact scaffolding to ensure safety and precision during installation.
Preservation of aesthetics
The wiring and refrigeration pipes were carefully concealed in neutral-colored capping , perfectly integrated with the existing wooden moldings. This allowed the architectural character to be preserved while ensuring a flawless finish.
Respect for immediate comfort
The installation was completed in a single day, minimizing the impact on occupants. From the moment it was put into operation, the difference in comfort was noticeable: a uniform and pleasant freshness, without unpleasant drafts.
Benefits for the customer
Thanks to this installation:
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The customer benefits from increased thermal comfort during hot summer days in Montreal.
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The energy bill is optimized thanks to the high efficiency of the air conditioner.
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The device brings added value to the residence, combining technical performance and respect for heritage design.
AirGreen: your HVAC partner in Montreal and surrounding areas
This project in Outremont demonstrates AirGreen's expertise in HVAC installation in a variety of residential settings, including period homes where every detail counts. Whether you're in Montreal, Laval, Longueuil, the North Shore, or the South Shore , we always adapt our methods to provide lasting comfort and impeccable finishes.
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 room, the outside wall, the line route and where the outdoor unit will go. That is where the capacity gets chosen.
Model, capacity and price, in writing. We also check whether the model qualifies for assistance programs.
Floors and furniture protected, wall plate position marked level, wall opening located.
A single opening, with the slope the drain needs to flow outside.
Set on a stand raised above the snow, with the clearances the manufacturer requires.
Connected, insulated and protected. The opening is then sealed against water, cold air and insects.
A dedicated circuit and an accessible disconnect near the outdoor unit.
Leak test, vacuum, then start-up and a check of heating and cooling.
Remote, modes, filters: we show you the essentials before we leave.
- The on-site estimateWe look at the room, the outside wall, the line route and where the outdoor unit will go. That is where the capacity gets chosen.
- The quoteModel, capacity and price, in writing. We also check whether the model qualifies for assistance programs.
- Getting readyFloors and furniture protected, wall plate position marked level, wall opening located.
- The wall openingA single opening, with the slope the drain needs to flow outside.
- The outdoor unitSet on a stand raised above the snow, with the clearances the manufacturer requires.
- Lines, cable and drainConnected, insulated and protected. The opening is then sealed against water, cold air and insects.
- The electrical workA dedicated circuit and an accessible disconnect near the outdoor unit.
- Tests and start-upLeak test, vacuum, then start-up and a check of heating and cooling.
- The walkthroughRemote, modes, filters: we show you the essentials before we leave.
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.
- Clean the indoor unit's filters.
- Clear leaves and debris left on the outdoor unit by winter.
- Test cooling before the first hot days.
- Clean the filters more often when the unit runs a lot.
- Keep plants away from the outdoor unit.
- Check that no water drips from the indoor unit.
- Rake the leaves around the outdoor unit.
- Test heating before the first cold days.
- Book periodic maintenance before winter.
- Keep snow away from the stand and the front of the unit.
- Let the unit defrost: it is normal.
- Never hit the ice on the fins; call us if the unit stays iced up.
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What people ask us about this kind of work
Does a wall-mounted heat pump heat in winter?
Wall-mounted or multi-zone: how do I choose?
Where does the outdoor unit go?
Are there grants?
Do I need a permit?
How cold can it heat?
How much can I save?
How is the LogisVert assistance calculated?
Is it noisy?
The outdoor unit is covered in ice: is that normal?
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).