Installation of an 18,000 BTU MIDEA35 wall-mounted heat pump in Sainte-Thérèse on the North Shore: a high-performance mini-split with a perfectly integrated exterior finish
AirGreen installs a MIDEA35 18,000 BTU wall-mounted heat pump in Sainte-Thérèse: efficient mini-split, neat exterior ductwork, robust wall bracket, and lasting HVAC comfort on the North Shore.
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The unit’s data sheet
The range as published on airgreen.ca: pick a size to see its capacity in deep cold.
| Size | Heating at −8 °C | Heating at −15 °C | Coldest certified point | COP at −15 °C | SEER | HSPF | Indicative LogisVert aid |
|---|---|---|---|---|---|---|---|
| Midea Série 35 9 000 | 11,000 | 13,500 | −30 °C: 7,500 | 2.0 | 33.3 | 14.6 | – |
| Midea Série 35 12 000 | 11,000 | 13,500 | −30 °C: 7,500 | 2.0 | 29.4 | 12.7 | $1,320 |
| Midea Série 35 18 000 | 19,300 | 22,600 | −30 °C: 11,900 | 2.34 | 25.6 | 16.2 | $2,316 |
According to NEEP, its certified maximum capacity at −30 °C (−22 °F) is 7,500 BTU/h, 83% of its nominal 9,000 BTU size.
At 8 °C, its certified maximum capacity reaches 17,200 BTU/h, 91% more than its nominal 9,000 BTU size.
According to NEEP, its certified heating capacity at −15 °C (5 °F) is 13,500 BTU/h, 150% of its nominal 9,000 BTU size. Its COP there is 2.00.
According to NEEP, its certified maximum capacity at −30 °C (−22 °F) is 7,500 BTU/h, 62% of its nominal 12,000 BTU size.
At 8 °C, its certified maximum capacity reaches 17,200 BTU/h, 43% more than its nominal 12,000 BTU size.
According to NEEP, its certified heating capacity at −15 °C (5 °F) is 13,500 BTU/h, 112% of its nominal 12,000 BTU size. Its COP there is 2.00.
According to NEEP, its COP at −15 °C is 2.34: the highest of the Série 35 line, which ranges from 2.00 to 2.00 at that temperature.
According to NEEP, its certified maximum capacity at −30 °C (−22 °F) is 11,900 BTU/h, 66% of its nominal 18,000 BTU size.
At 8 °C, its certified maximum capacity reaches 29,700 BTU/h, 65% more than its nominal 18,000 BTU size.
Data read live from the airgreen.ca page of each size (NEEP / AHRI certified performance). When the title names the installed size, it is highlighted; otherwise the whole range is shown. The aid shown is today’s, using Hydro-Québec’s rule ($120 per 1,000 BTU/h at −8 °C); amounts quoted in the article date from its publication. Only Hydro-Québec confirms the assistance granted.A dash in the aid column: amount to be confirmed for this model.
The article, chapter by chapter
MIDEA35 18,000 BTU Installation Designed for a Brick Facade in Sainte-Thérèse
In Sainte-Thérèse, on the North Shore, our AirGreen team installed a MIDEA35 18,000 BTU wall-mounted heat pump, a mini-split system designed to provide excellent comfort in air conditioning and supplementary heating in a multi-level residence. This project stands out for a very important visual element: the clean integration of the refrigeration lines on a red brick facade, with a vertical conduit neatly aligned between the windows.
The photo clearly shows the Midea outdoor unit installed on a sturdy wall bracket, slightly above ground level, with a long protective conduit running up the facade to the floor served by the indoor unit. This type of installation requires precise planning, as the exterior finish becomes as important as the mechanical performance. In a residential area like Sainte-Thérèse, where many buildings have brick facades visible from the yard or common areas, an HVAC installation must remain clean, straight, stable, and discreet.
In this case, the client wanted an effective solution to improve comfort in a significant area of the house, without major interior work and without compromising the building's exterior appearance. The MIDEA35 18,000 BTU perfectly met this need: higher capacity than a 12,000 BTU model, modern technology, quiet operation, and a wall-mounted installation suitable for the realities of North Shore residences.
Why a MIDEA35 18,000 BTU was the right choice for this project
The 18,000 BTU capacity is generally suitable for more generous spaces, open-plan areas, well-configured entire floors, or areas where cooling and heating needs are greater. In Sainte-Thérèse, many houses built with brick walls and large windows can accumulate heat during the summer, especially when the orientation favors sunlight for several hours.
The MIDEA35 18,000 BTU wall-mounted heat pump offers an excellent compromise for homeowners who want to:
- Quickly improve comfort in a main living area.
- Reduce indoor humidity during hot days.
- Get efficient supplementary heating during transitional seasons.
- Install a ductless system, with limited impact on interior walls.
- Benefit from inverter technology that modulates power according to actual demand.
- Enjoy a device known for its good balance between performance, reliability, and installation cost.
For this project, the 18,000 BTU model allowed us to go beyond a simple wall-mounted air conditioner intended for a small room. It was instead a system capable of contributing concretely to the overall comfort of the targeted space, both in summer and during cooler periods.
An outdoor installation that highlights the importance of planning
One of the most interesting aspects of this project is the vertical routing of the lines. The outdoor conduit runs several feet along the brick facade, in a straight and clean line, to reach the planned interior location. This choice is not only aesthetic: it also protects the refrigeration lines, wiring, and drain, while maintaining a durable finish against the elements.
On a wall-mounted heat pump installation, the refrigeration lines must be protected against:
- UV rays.
- Rain.
- Snow.
- Ice.
- Accidental impacts.
- Movements caused by temperature variations.
- Premature insulation wear.
The conduit installed on this facade therefore plays a major technical role. It improves the appearance of the installation, but also contributes to its durability. At AirGreen, we attach great importance to this type of detail, because an installation that looks clean on the day of installation must also remain solid and functional several years later.
The wall mount: a solution adapted to Quebec winters
The outdoor unit is fixed on metal wall mounts, above the foundation. This configuration is very common for our installations in Montreal, Laval, Longueuil, on the North Shore and the South Shore, as it offers several advantages in the Quebec climate.
A well-installed wall mount allows you to:
- Keep the outdoor unit above normal snow accumulations.
- Reduce the risk of obstruction around the unit.
- Facilitate drainage during defrost cycles.
- Limit direct exposure to ground moisture.
- Maintain good access for HVAC maintenance.
- Avoid unnecessarily occupying ground space.
In this project in Sainte-Thérèse, the presence of vegetation, a clear foundation, and a relatively narrow outdoor space made the wall mount particularly relevant. The unit is positioned to preserve access around the building while respecting the condenser's airflow requirements.
The importance of clearance around the condenser
A heat pump cannot operate at its full potential if air does not circulate properly around the outdoor unit. The front fan must be able to exhaust air efficiently, while the sides of the unit must allow sufficient air intake. An installation too tight against an obstacle, a hedge, a fence, or a structure can lead to a decrease in performance.
In this installation, the Midea outdoor unit is well cleared in front, with enough space to allow the fan to operate correctly. The positioning also takes into account the facade, basement windows, and the vegetated area at the base of the wall.
This type of assessment is essential during an HVAC installation. We always analyze the outdoor environment before fixing the unit, because a bad position can increase perceived noise, reduce energy efficiency, and complicate maintenance interventions.
A wall-mounted heat pump adapted for four-season comfort
The MIDEA35 18,000 BTU is appreciated for its ability to offer stable comfort without requiring a duct network. For homeowners who wish to modernize their comfort without entirely replacing their main system, a wall-mounted heat pump represents a very practical solution.
In air conditioning mode, the appliance effectively cools the serviced space while better controlling humidity. This is a major advantage in homes in the greater Montreal area, where summers are often humid and heat can accumulate on upper floors.
In heating mode, heat pump technology allows heat to be produced with optimized electricity consumption, particularly during transitional seasons. In spring and autumn, the system can reduce the use of main heating and improve comfort without overheating the entire house.
For a homeowner in Sainte-Thérèse, this means better temperature control, more flexible use, and more uniform comfort in the targeted area.
The challenge of a multi-level facade
The photo shows a multi-level building, with windows distributed across the facade. This configuration requires particular attention to the routing of the lines. Obstacles must be avoided, technical distances respected, the appearance of the brick preserved, and an adequate slope ensured when drainage is involved.
In this project, the vertical conduit was installed along a visually logical axis, between existing openings. This choice gives a structured appearance to the installation, instead of having an improvised or too visible route. The color of the conduit blends well with the brick, which contributes to better visual integration.
This detail is particularly important in residential areas of Sainte-Thérèse, Boisbriand, Blainville, Rosemère, and Laval, where many clients want to benefit from a modern mini-split while maintaining a neat exterior facade.
Key steps in this HVAC installation
To successfully complete this type of installation, our team follows a rigorous work sequence. Each step influences the system's final performance.
1. Indoor location analysis
Before installing the outdoor unit, we determine the optimal location for the indoor unit. The goal is to allow good air distribution in the targeted area, without blowing directly on occupants for long periods and without being blocked by a wall, furniture, or a poorly oriented hallway.
2. Choosing the line route
The route between the indoor and outdoor units must be as clean and efficient as possible. In this project, the vertical distance required a well-planned route, with continuous protection of the lines on the facade.
3. Wall mount fastening
The support must be perfectly anchored, level, and adapted to the weight of the outdoor unit. A solid installation reduces vibrations and improves system durability.
4. Outdoor unit installation
The MIDEA35 was installed on the support, respecting the required clearances. The unit must remain stable, accessible, and well ventilated.
5. Refrigerant and electrical connection
Refrigerant lines, wiring, and connections are carefully made. Vacuuming, leak checks, and functional tests are essential to ensure system performance.
6. Commissioning and client explanations
Once the system is operational, we test the main modes and explain to the client how to effectively use the wall-mounted heat pump, how to clean the filters, and when to schedule maintenance.
Common mistakes to avoid with a wall-mounted installation
A project like this clearly shows why you shouldn't improvise the installation of a wall-mounted air conditioner or a heat pump. Even with a good appliance, poor installation can create long-term problems.
The most common mistakes are:
- Installing the outdoor unit too low, directly exposed to snow.
- Neglecting the protection of the lines on the facade.
- Choosing an unsightly or difficult-to-maintain line route.
- Improperly sizing the appliance relative to the space.
- Forgetting the importance of air clearance around the condenser.
- Installing the unit near a window without considering noise or vibrations.
- Entrusting refrigerant connection to an unqualified person.
- Neglecting condensation drainage.
At AirGreen, we regularly see installations that could have been more durable with better planning from the outset. That's why we emphasize site analysis, material quality, and exterior finish.
MIDEA35 18,000 BTU: performance, efficiency, and daily comfort
The MIDEA35 range is often chosen for its balance between price, performance, and reliability. The 18,000 BTU model is particularly relevant when the client wishes to air condition or heat a larger area than a single room.
Among the benefits sought by homeowners:
- Power adapted to open spaces or more demanding floors.
- Fast and comfortable air conditioning.
- Better dehumidification during summer.
- Efficient supplementary heating.
- Inverter technology that adjusts capacity to actual needs.
- Relatively quiet operation.
- Ductless installation, ideal for many existing homes.
For residences in Sainte-Thérèse and the surrounding areas, this type of system can transform indoor comfort without requiring major renovations. It installs quickly, requires little interior space, and offers appreciable daily flexibility.
Subsidies and energy efficiency: what to check
Clients often ask us if their wall-mounted heat pump is eligible for financial aid. Subsidy programs can vary depending on the period, the exact model, certifications, and technical criteria required. For a MIDEA35 18,000 BTU, it is important to check the specific information of the installed model, including performance references and eligibility for current programs.
At AirGreen, we help our clients understand the usual steps:
- Keep the detailed invoice.
- Verify the exact model installed.
- Confirm eligibility according to the available program.
- Submit the required documents on time.
- Follow the instructions related to the refund request.
This aid is particularly useful for homeowners in Montreal, Laval, Longueuil, the North Shore, and the South Shore, who often compare several models based on the real cost after subsidy.
An exterior finish that inspires confidence
The final appearance of an installation is an important indicator of the care put into the project. In this installation in Sainte-Thérèse, the vertical duct is straight, well-positioned, and consistent with the facade. The outdoor unit is solidly installed, with adequate clearance and a clear support structure.
A clean finish has several advantages:
- It better protects the components.
- It facilitates maintenance.
- It reduces the risk of damage.
- It improves the exterior appearance of the property.
- It demonstrates better execution rigor.
For us, a successful HVAC installation must be efficient, but also well-integrated. The ducts should not be left to chance, and the outdoor unit should be thoughtfully placed.
Recommended HVAC maintenance after installation
To maintain the performance of the MIDEA35 18,000 BTU, regular maintenance is recommended. A clean system consumes less, performs better, and lasts longer.
Simple actions to remember:
- Clean the indoor unit filters according to use.
- Keep the outdoor unit clear of leaves, branches, snow, and debris.
- Check that nothing is blocking the fan's air outlet.
- Observe any changes in noise or performance.
- Schedule periodic professional maintenance.
- Do not let vegetation invade the area around the condenser.
In this project, the position on a wall mount facilitates access to the device and limits certain risks associated with ground accumulation. This is a concrete advantage for long-term maintenance.
The AirGreen experience on the North Shore
AirGreen regularly performs installations of wall-mounted heat pumps, wall-mounted air conditioners, and mini splits in Sainte-Thérèse, Boisbriand, Blainville, Rosemère, Laval, as well as throughout the greater Montreal area. This local experience allows us to anticipate frequent constraints: brick walls, confined spaces, visible facades, co-ownerships, limited rear access, vegetation, close neighbors, and aesthetic requirements.
Each project requires a tailored solution. In some cases, the challenge is noise. In others, it's the distance between the indoor and outdoor units. Here, the main challenge was to achieve a clean exterior installation on a high facade, with a long, protected vertical run and an outdoor unit positioned sustainably.
This installation of the MIDEA35 18,000 BTU in Sainte-Thérèse represents exactly the type of work we love to do: an efficient solution, a meticulous finish, and an installation designed for real Quebec conditions.
A lasting result for measurable comfort
Once commissioning is complete, the client benefits from a system capable of concretely improving indoor comfort. The MIDEA35 18,000 BTU wall-mounted heat pump provides an effective solution for summer air conditioning needs and supplementary heating during cooler periods. The exterior installation, meanwhile, was designed to remain clean, stable, and accessible.
The result is a complete HVAC solution: a well-chosen appliance, a thoughtful location, a well-integrated duct, a solid wall mount, and an installation executed with precision. For homeowners in Sainte-Thérèse considering adding a mini-split, this project demonstrates the importance of working with a team that masters both the technical aspect and the exterior finish.
The job tools
Two quick checks with real numbers: what heat costs, and what your current heaters add up to in BTU/h.
Baseboards and electric furnaces turn 1 kWh of electricity into 1 kWh of heat. A heat pump delivers more: that is its COP. At Hydro-Québec’s rate D (11.142¢/kWh above 40 kWh a day, since 1 April 2026):
Hydro-Québec: a heat pump can be up to three times more efficient than baseboards for heating in the colder months.
Estimate per kWh of heat, at the chosen temperature, using the certified COP from the product page. Taxes, access charge and backup heat not included.
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.
How the job unfolds
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.
What we check on a job like this one
Each number is a point we check on site. Switch between summer and winter to watch air and heat move.
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.
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.
Good habits, once the unit is in place
Six simple habits that keep the unit going. Your list stays on this device.
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.
The right pages, at the right time
Four statements: true or false?
It all comes down to details you have just seen.
1. In heating mode, the outdoor unit can produce water.
During defrost cycles. That water must drain away without forming ice.
2. You pick the capacity with a simple square-footage rule.
Windows, insulation, orientation and how the room is used all count. Capacity is chosen on site.
3. A multi-zone connects several indoor heads to a single condenser.
One head per room, all on the same condenser. Each room keeps its own temperature.
4. The disconnect can sit behind the patio furniture.
It must stay accessible: it is what shuts the unit off for service.
0 / 4 right answers
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?
No question matches. Write to us: we answer.
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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).