Installation of an LG (inverter range) wall-mounted heat pump in Saint-Léonard
In Saint-Léonard, AirGreen installs an LG wall-mounted heat pump : wall brackets, vertical chute, secure power supply, winter performance. Careful HVAC installation and simplified HVAC maintenance for 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.
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 exemplary and durable exterior assembly
In Saint-Léonard (Montreal) , we are finalizing the installation of an LG wall-mounted heat pump for a recent brick duplex. The condenser is mounted on sturdy wall brackets , above the level of snow projection and splashes, with rear and side clearances that facilitate ventilation and service access. The refrigerant connections are protected in a dark brown vertical chute that runs along the common wall joint to the top floor. This finish harmonizes with the neighboring brick and plaster, while protecting the insulation from UV, rain, and ice.
Under the unit, a disconnect box secures the power supply during maintenance. The system operates silently thanks to anti-vibration silent blocks and chemical anchors anchored in the brick facing, designed to withstand the dynamic loads of the compressor and the stresses caused by freezing and thawing. The result: a clean, durable HVAC system ready to face Montreal winters.
Installation process and technical choices
Envelope analysis and positioning
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Ventilated rear facade : the raised installation limits snow retention and maintains free flow of defrosting condensate.
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Short and readable path : the vertical chute joins the drilling at the height of the interior head, which reduces pressure losses and simplifies future diagnosis.
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Neighborhood acoustics : the device is clear of nearby windows; the orientation of the blowing avoids reverberations towards the neighboring courtyard.
Refrigerant connections and drain
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1/4–3/8 copper insulated with high density cellular foam, sleeves sealed in the conduit.
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Bending radius respected at each change of direction, with anti-friction sheaths to protect the insulation.
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Gravity drain from the interior head, continuous slope towards the outside, anti-runoff tab to keep water away from the facings.
Power supply
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Dedicated circuit from the panel, rating as per LG nameplate.
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Proximity switch under the unit, waterproof cable glands and rigid UV conduit.
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Grounding and service loop provided for interventions.
Supports and anchors
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Painted galvanized steel brackets , permissible load > 3× the weight of the condenser.
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Threaded rods + chemical anchors in the brick core (not just the mortar).
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High resilience rubber anti-vibration wedges to attenuate transmission to interior walls.
Sizing and performance
In this project, the LG 9,000 to 12,000 BTU inverter wall unit covers the living area of the top floor and the adjacent landing. Continuous modulation allows:
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a stable setting without overheating or short cycles;
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high seasonal efficiency thanks to part-load operation;
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maintaining capacity in heating mode in cold weather (low temperature range suitable for Montreal winters).
This configuration advantageously replaces the old wall-mounted air conditioner in the summer and supplements the existing heating in the winter, while reducing energy expenditure.
Safety, waterproofing and finishes
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Air barrier and vapor barrier reconstituted at the piercing (sleeve + closed-cell foam + elastomeric mastic).
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Defrosting : free flow of winter condensate, without stalactites on the brick.
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UV protection : cable duct and collars resistant to solar rays; stainless steel screws to prevent rust marks.
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Readable trajectory : deliberate choice of a uniform cover from the bottom to the roof drain, which makes the installation scalable in the event of adding a second head in the future.
Instrumented commissioning
Our technicians carry out a vacuum < 300 microns with a resistance test, check the refrigerant charge according to the actual length of the lines, then check:
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compressor intensity and voltages,
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delta-T supply air/return air ,
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operating pressures and defrost sequence.
A commissioning report is provided to the customer, useful for the manufacturer's warranty.
What the owner earns on a daily basis
Comfort and silence
The LG indoor head delivers a laminar flow along the ceiling, then redistributes it to adjacent rooms. In night mode , the reduced speed drops to an almost imperceptible level, which improves sleep compared to a traditional wall-mounted air conditioner or a window unit.
Energy savings
The inverter compressor modulates continuously. Coupled with an optimized refrigeration path (straight chute, few bends), we obtain a measurable reduction in kWh during the summer period and economical heating support during the off-season.
Simplified maintenance
Access to the condenser is straightforward: the backyard allows for annual fin rinsing . Inside, the washable filters can be removed without tools. We offer an annual HVAC maintenance plan **** to maintain performance and preserve the warranty.
Grants and administrative support
LG high-efficiency wall-mounted heat pumps are generally eligible for support programs in effect in Greater Montreal, subject to a corresponding AHRI number and validated low-temperature performance. AirGreen supports:
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eligibility verification (model, AHRI number),
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compilation of installation evidence ,
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support for filing applications .
This assistance applies to customers in Montreal, Laval, Longueuil, North Shore and South Shore .
Best practices that we systematically apply
1. Clearances and ventilation
Minimal clearance around the condenser, 60 cm on the sides and obstacle control under the unit. No air discharge towards an intake, and no obstruction by garden tubs or bicycles.
2. Snow management
Installation height > 30–35 cm above finished ground; front clearance > 1 m in winter. If exposed to loaded roofs, add a snow guard .
3. Protection of the facings
Drain outlet oriented towards a drainage area, without runoff along the brick. Gentle periodic cleaning, without high-pressure cleaner on the fins.
4. Wiring and security
CSA cables in rigid sheath, switch within easy reach, clear circuit markings in the electrical panel.
5. Forecast of evolution
Chute sized for an additional line if a second head is added; space left on the brackets for future replacement without re-drilling.
Testimony and follow-up
The owner notes a significant decrease in noise in the courtyard compared to the previous unit and stable temperature upstairs. After the first month of use, summer electricity consumption drops, and the mid-season heat input allows the main heating to be delayed. AirGreen plans a pre-winter check : defrost test, electrical tightening check, filter wash and chute inspection.
AirGreen, your local reference
Our teams operate weekly in Montreal, Laval, Longueuil, and on the North and South Shores for new projects, replacements, and route optimizations. Our promise: a documented HVAC installation , honest advice on capacity and brand, and responsive after-sales service . This project in Saint-Léonard is a prime example: a well-sized LG heat pump , integrated chute, durable anchors, and preserved winter performance.
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).