Installation of a MIDEA35 18,000 BTU wall-mounted heat pump in Terrebonne: a high-performance mini-split to better air-condition an open living area and a central corridor
AirGreen installs an 18,000 BTU MIDEA35 wall-mounted heat pump in Terrebonne: high-performance mini-split, central location, optimized comfort, and meticulous HVAC installation.
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.
A strategic wall-mounted installation in a Terrebonne home where air circulation made all the difference
In this Terrebonne residence, our AirGreen team installed a MIDEA35 18,000 BTU wall-mounted heat pump, a wall-mounted air conditioner – mini-split type, in a particularly interesting location: above an interior opening, between a circulation area, an adjoining kitchen, and a nearby bathroom. The photo clearly shows the real context of the project: a wall-mounted unit installed high up, in a central hallway, with an open kitchen on the left and an adjacent room on the right.
This type of installation is common in homes on the North Shore, particularly in Terrebonne, Mascouche, Repentigny, Blainville and in several residential areas where rooms communicate with each other through large openings rather than a completely open-plan area. The challenge is therefore not just to install an efficient machine, but to choose a location that allows the air-conditioned or heated air to spread naturally into the most used areas of the house.
In this case, the client's objective was clear: to improve overall comfort in a living area where heat tended to accumulate, especially during hot and humid periods. The kitchen, visible in the photo, represented an additional source of heat during cooking, while the central hallway served as a passage point to several rooms. A wall-mounted heat pump of 18,000 BTU offered a relevant capacity here to support better temperature stability, without resorting to a more intrusive central system.
Why a MIDEA35 18,000 BTU was suitable for this configuration
The MIDEA35 18,000 BTU is a wall-mounted solution well-suited for residential spaces where a higher capacity is desired than small bedroom or office units. An 18,000 BTU unit can be particularly relevant when an open area, a main floor, a larger room, or an area with several openings to neighboring rooms needs to be treated.
At AirGreen, we never recommend a heat pump based solely on a general rule of thumb for surface area. A successful installation requires a complete understanding of the building. In this Terrebonne home, several elements were evaluated before confirming the choice of the unit and its location:
- the kitchen's position and its heat input;
- the width of openings between rooms;
- the volume of air to be treated;
- the ceiling height;
- natural circulation between the hallway and adjacent rooms;
- available walls for installation;
- possible routing of refrigerant lines;
- future access for HVAC maintenance;
- aesthetic integration of the unit in an already furnished room.
The installation visible in the image illustrates an important decision: rather than placing the unit randomly in the largest room, we chose a high and central point, allowing the unit to project air into a thoroughfare and contribute to the comfort of adjacent spaces. This approach is often more effective in homes where rooms are separated by wide openings, but where load-bearing walls and interior divisions limit options.
An installation above a door: precision, clearances, and finish
Installing a wall unit above an interior opening can be very advantageous, but it requires precise execution. In the photo, the heat pump is positioned above a door leading to a bathroom. The available space between the top of the door frame and the ceiling had to be used carefully. The unit had to be installed perfectly level, with sufficient clearance for air intake above and effective projection through the front louvers.
Poor installation in this type of location can cause several problems:
- restricted air intake if the unit is too close to the ceiling;
- misdirected air projection;
- vibrations if the wall mount is not properly anchored;
- difficulty accessing for filter cleaning;
- unbalanced visual appearance in a high-traffic area;
- poor drainage if the evacuation slope is poorly planned.
Our team therefore proceeded with particular attention to wall positioning, alignment, fastening, and the technical trajectory behind the unit. In an occupied home, every detail counts: walls are finished, floors are in place, door frames must remain clean, and the client expects a discreet, stable, and durable result.
A wall-mounted heat pump designed for real comfort, not just rated power
The 18,000 BTU capacity allows this MIDEA35 to meet greater needs than a small 9,000 or 12,000 BTU unit. However, power alone does not guarantee comfort. A heat pump must be installed to promote good air circulation, especially in a living area with a kitchen, a hallway, and several adjacent rooms.
In this Terrebonne installation, the advantage of the central positioning is that air can circulate towards the kitchen and the passage area, instead of being concentrated in a single closed room. This is an essential point for homeowners who want to air condition more than just one room, without necessarily installing a multi-zone system.
The MIDEA35 18,000 BTU also provides modulating comfort. Rather than just operating at full power and then suddenly stopping, this type of mini-split adjusts its operation according to demand. This modulation helps maintain a more stable temperature, reduce uncomfortable variations, and improve daily operating efficiency.
Features visible in the photo: a typical residential project, yet technically demanding
The image shows several details that make this installation representative of many projects carried out by AirGreen in the greater Montreal area, in Laval, in Longueuil, on the North Shore, and on the South Shore.
An adjoining kitchen, a source of heat and air movement
To the left, the kitchen is visible with a wide opening. In a home, the kitchen is often an area where temperature rises faster: cooking, appliances, sun exposure, frequent circulation. Installing a wall-mounted heat pump capable of influencing this area significantly improves daily comfort.
A central area rather than an isolated wall
The unit was not installed in a remote corner or a closed room. It was placed in a high-traffic area. This decision allows for more effective treatment of ambient air around communicating rooms. This is often an excellent strategy for Terrebonne homes built with traditional divisions but fairly wide interior openings.
An installation height that maximizes reach
Placed high up, the unit can diffuse air over usual obstacles: furniture, frames, occupant movements. The louver settings can then be adjusted to direct the air to avoid an unpleasant direct draft while maintaining good coverage.
A sober visual integration
The white wall unit discretely integrates into an interior environment with light-colored walls. The objective was not to make the appliance completely disappear, but to install it cleanly, straight, and consistently with the room. For us, a good HVAC installation must be as technically well-executed as it is visually acceptable.
Technical challenges of this HVAC installation in Terrebonne
Planning pipe routing without compromising interior aesthetics
In a wall-mounted installation, the indoor unit is only part of the job. The refrigerant lines, communication cable, condensation drain, and connection to the outdoor unit must be precisely planned. When the unit is placed above a door, maneuverability is more limited.
Our team had to consider the wall structure, the position of the opening, the ceiling, and the orientation towards the outside. A well-planned route limits unnecessary drilling, ensures a correct slope for the drain, and avoids cumbersome interior finishing.
In several residential installations in Terrebonne, we see errors caused by rushed planning: visible ducts in poorly chosen locations, complicated drainage, difficult access for service, or unit installed too low to comply with piping constraints. Our method consists of validating the complete technical path before the final mounting of the machine.
Ensuring reliable drainage in cooling mode
A wall-mounted heat pump used as an air conditioner naturally produces condensation. This water must be properly evacuated, with an adequate slope and a reliable path. In a space above a door, drainage must be considered from the outset to avoid any risk of future leaks.
A poorly installed drain can lead to:
- water droplets under the unit;
- moisture accumulation;
- odors;
- operational shutdowns;
- damage to walls or door frames.
In this installation, we paid particular attention to condensation drainage. This work is often invisible to the client when everything is working well, but it is one of the foundations of a durable installation.
Securely mounting the unit on an existing wall
An 18,000 BTU unit requires stable wall mounting. Even though the indoor unit remains relatively compact, it must be fixed to a surface capable of supporting it without vibration or displacement. The mount must be perfectly level, as a slight misalignment can affect drainage and the appearance of the installation.
Our technicians always check the anchoring, level, stability, and final alignment. This rigor avoids long-term problems and contributes to the system's quiet operation.
Minimizing disruptions in an occupied home
The construction site visible in the photo is in an occupied home, with finished floors, furnished rooms, and interior circulation. An HVAC installation in this context requires cleanliness and organization. We protect work areas, plan movements, reduce dust, and leave the space clean once the startup is complete.
This practical dimension is important for our clients. A heat pump installation should not feel like a large, disorganized construction site. At AirGreen, we aim for efficient, clean, and structured execution.
Practical tips for effective use of a MIDEA35 18,000 BTU after installation
Once the unit is installed, comfort also depends on how it is used. We took the time to explain to the client the best practices to fully enjoy their MIDEA35 wall-mounted heat pump.
Avoid overly frequent temperature changes
It is preferable to set a comfortable temperature and let the system modulate. Constant adjustments force the unit to react unnecessarily and can reduce comfort stability.
Use louvers to direct air intelligently
In this configuration, louver orientation is important. Air does not necessarily need to be directed straight at a person. It is often more effective to project it into the circulation area so that it gradually mixes with the ambient air.
Clean filters regularly
Cleaning filters is simple but essential. Clogged filters reduce airflow, increase system effort, and negatively impact air quality. For a house where the appliance is used frequently, periodic maintenance is recommended.
Plan for professional maintenance as needed
Professional HVAC maintenance allows for checking the general condition of the indoor unit, drain, outdoor unit, connections, and performance. A well-maintained heat pump generally offers better comfort, better efficiency, and a more stable lifespan.
Mistakes to avoid before installing a wall-mounted air conditioner in Terrebonne
Homeowners shopping for a wall-mounted heat pump or wall-mounted air conditioner in the Terrebonne region often focus on price or brand. These elements matter, but they are not enough. Here are the most common mistakes we help our clients avoid.
Installing a unit that is too weak for an open-plan area
A 12,000 BTU unit can be excellent in certain contexts, but insufficient for a larger or more open area. Here, the choice of a MIDEA35 18,000 BTU better met the volume of air to be treated.
Placing the unit in the most visible room without analyzing air circulation
The best wall is not always the most obvious. In this house, the central hallway offered a better diffusion logic than some more distant walls.
Neglecting the heat generated by the kitchen
An adjoining kitchen can increase the thermal load. When sizing a heat pump, the actual uses of the house must be considered.
Choosing an installer without experience in complex residential configurations
An installation above a door, near an opening, and in a high-traffic area requires more precision than an installation on a large, clear wall. The technician's experience directly influences the final result.
Subsidies and eligibility: an aspect to validate before purchasing
Several clients from Terrebonne, Montreal, Laval, Longueuil, the North Shore, and the South Shore want to know if their heat pump is eligible for financial aid. The available programs, technical criteria, and applicable amounts can vary depending on the exact model, installation date, and current requirements.
At AirGreen, we assist our clients in understanding the required documents: detailed invoice, installed model, technical information, and necessary proofs when the applicable program requests them. This step must be approached seriously, as a simple confusion between two similar models can compromise an application.
For a MIDEA35 18,000 BTU, we always recommend validating eligibility according to the precise technical sheet of the installed unit and the criteria in effect at the time of the project.
Why AirGreen is a reliable choice for a Midea installation in Terrebonne
Our field experience allows us to quickly recognize constraints that are not always visible during a simple online search. An installation like this requires combining thermal analysis, technical planning, compliance with standards, interior finishing, and usage advice.
For this project in Terrebonne, our contribution stood out through:
- a realistic assessment of comfort needs;
- a capacity choice adapted to the target area;
- a central positioning to promote air circulation;
- a clean installation above an interior opening;
- particular attention to drainage;
- a solid and well-aligned mounting;
- clear explanations provided to the client;
- a professional approach designed for the long term.
AirGreen regularly performs installations of wall-mounted heat pumps, wall-mounted air conditioners, mini split, multi-zone, and central systems in the greater Montreal area, in Laval, Longueuil, on the North Shore, and on the South Shore. Each building imposes its own constraints, and it is precisely this reality that makes our work so important.
A final result adapted to daily life
The result obtained in this Terrebonne home corresponds exactly to what an owner looks for in a well-designed residential installation: a high-performance wall unit, cleanly installed, capable of improving the comfort of living spaces without excessive work or visual clutter.
The MIDEA35 18,000 BTU wall-mounted heat pump offers a concrete answer to a real need here: better managing heat in a central area of the house, supporting comfort in the kitchen and adjoining rooms, and providing an efficient auxiliary heating solution during cooler periods.
For homeowners considering an HVAC installation in Terrebonne, this project shows the importance of choosing not only the right equipment but also the right location and the right team. A well-installed heat pump becomes an everyday comfort amenity. A poorly placed heat pump quickly becomes a source of compromise. At AirGreen, we work to ensure that each installation is thoughtfully planned, clean, durable, and truly adapted to the building.
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.
What the unit delivers when it is cold
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.
And at your place?
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.
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.
Which type of equipment for your project?
Pick what looks like your need.
Four mistakes we do not make
Flip each card to see what we do instead.
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.
Useful pages for what comes next
More jobs to see, near you
By town, by equipment or by region: browse more than 4,700 published projects.
Each dot: a town where AirGreen has published projects. The glowing dot: this job.
Tell us about your house. We come and see it for free.
The on-site estimate is free and the quote follows within 24 hours.
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).