Installation of a MIDEA MIDEA35 wall-mounted heat pump in Napierville: seamless integration of the indoor unit near the ceiling
MIDEA35 wall-mounted heat pump installed in Napierville by AirGreen: indoor unit mounted near the ceiling, comfort down to -30 °C, high efficiency, and HVAC installation tailored to the room.
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.
In Napierville, an installation where the positioning of the wall-mounted unit made all the difference
This installation of Midea MIDEA35 wall-mounted heat pump in Napierville illustrates an aspect we consider essential at AirGreen: a high-performance heat pump must also be positioned correctly within the room.
In the photograph taken after our work, the Midea indoor unit is installed in the upper part of the wall, just below the ceiling. A ceiling fan is nearby, and an opening is visible lower down on the same wall. This configuration therefore required careful consideration of the unit’s height, the direction of airflow, and the space available around the unit.
The result is a discreet, well-integrated installation: the wall-mounted heat pump occupies an area that does not encroach on the living space and keeps the lower part of the wall available, while allowing the air outlet louver to direct air into the room.
The selected model, the MIDEA35The selected model, the, belongs to Midea’s high-end wall-mounted series. The manufacturer’s documentation describes it as a heat pump operating with the refrigerant R-454B, compatible with heating conditions down to -30 °C and, depending on its capacity, delivering efficiency of up to 33.3 SEER2 and 22.0 HSPF2.
Why the indoor location matters
When a homeowner compares several heating and heating and cooling in Napierville, attention is often focused on the brand, the number of BTUs, and the price. However, the location of the indoor unit can have a considerable impact on actual comfort.
A wall-mounted unit works by drawing room air in through its upper section, then circulating it through its heat exchanger before redistributing it through the lower louver. It therefore needs sufficient space around it to allow adequate airflow.
Several elements were visible in the installation area on this job:
- the relatively low ceiling;
- a ceiling fan;
- the fan control chains;
- an opening located below the unit;
- a section of wall wide enough to accommodate the Midea unit.
Rather than installing the heat pump lower simply because that area appeared available, we used the upper part of the wall to promote more natural air distribution throughout the room.
This approach is particularly useful in air conditioning because cool air naturally descends. In heating mode, airflow and louver adjustment become equally important to push heat toward the occupied area rather than letting it accumulate near the ceiling.
Thoughtful coexistence with the ceiling fan
The presence of a ceiling fan is an interesting feature of this heat pump project Midea heat pump in Napierville.
A fan and a heat pump can be used perfectly well in the same room, but their positioning should be carefully considered. The goal is to prevent the fan from directly disrupting the heat pump's airflow or placing both appliances in a configuration that limits their operation.
In the photo, the Midea unit is installed on the wall while the fan remains centered farther into the room. The heat pump's air outlet louver can therefore direct air toward the occupied area.
In some situations, the ceiling fan may even help redistribute air in a large room, provided it is used intelligently. During heating periods, slow circulation can help bring some of the warm air accumulated near the ceiling back toward the occupied area. In summer, it can complement the feeling of coolness created by the wall-mounted air conditioning.
MIDEA35: a series designed for Quebec's climate
The range MIDEA35 provided in the manufacturer's documentation includes three cooling capacities:
- 9,000 BTU/h;
- 12,000 BTU/h;
- 18,000 BTU/h.
The official combinations are as follows:
| Capacity | Indoor unit | Outdoor unit | AHRI reference |
|---|---|---|---|
| 9,000 BTU/h | MSESU-H09B-2A | MO1SS-H09B-2A | 215471386 |
| 12,000 BTU/h | MSESU-H12B-2A | MO1SS-H12B-2A | 215471387 |
| 18,000 BTU/h | MSESU-H18B-2A | MO1SS-H18B-2A | 215471388 |
The exact capacity installed at this site cannot be determined with certainty from the photograph. We therefore prefer not to arbitrarily assign a BTU rating to this installation.
However, Midea presents all three configurations as Cold Climate V6.1, using R-454B.
Performance varies according to capacity
MIDEA35 performance is not identical across all sizes.
Midea publishes the following values:
- 9,000 BTU: 33.3 SEER2 and 22.0 HSPF2 IV;
- 12,000 BTU: 29.4 SEER2 and 14.5 HSPF2 IV;
- 18,000 BTU: 25.6 SEER2 and 16.2 HSPF2 IV.
These differences highlight why it is important to compare the exact model number rather than relying solely on the series name.
A homeowner who sees “MIDEA35” in a quote should also check:
- BTU capacity;
- indoor unit number;
- outdoor unit number;
- AHRI reference;
- dimensions;
- electrical requirements;
- refrigerant piping dimensions.
At AirGreen, these checks are part of our approach when we prepare a HVAC installation in Montréal, Laval, Longueuil, on the North Shore or the South Shore.
Heating down to -30 °C: what this really means
For all three MIDEA35 configurations, the published operating range in heating extends down to -30 °C. In cooling mode, Midea indicates a range up to 50 °C.
This -30 °C figure is obviously relevant in Quebec, but it must be interpreted correctly.
A minimum operating temperature does not mean that the heat pump provides exactly the same amount of heat at -30 °C as it does at 0 °C. Available capacity varies with outdoor conditions.
The MIDEA specification sheet provides a more precise figure at -15 °C :
- 13,500 BTU/h for the 9,000 and 12,000 BTU versions;
- 22,600 BTU/h for the 18,000 BTU version.
For us, this type of figure is particularly useful when assessing a home's needs and determining the extent to which a heat pump can contribute to heating during cold periods.
Variable-speed technology: fewer temperature fluctuations in the room
The MIDEA35 uses Midea's variable-speed technology.
Unlike a conventional system that operates mainly through on-off cycles, a variable-speed compressor can adjust its output to the room's actual needs.
The brochure explains that this technology allows the compressor to run continuously as temperature demand changes and helps limit temperature fluctuations.
In practice, when the requested temperature has almost been reached, the system can gradually reduce its operation rather than shutting down completely.
This modulation is particularly valuable in:
- bedrooms;
- workspaces;
- living rooms;
- open-concept homes;
- rooms where a more stable temperature is desired for long periods.
An indoor unit that can operate at a very low noise level
The presence of the ceiling fan in our photo also highlights another common concern: noise.
For the MIDEA35, the published indoor sound levels can drop as low as 19 dB(A) on the 9,000 and 12,000 BTU versions, and up to 16 dB(A) on the 18,000 BTU version under certain operating conditions.
The noise actually perceived naturally depends on the fan speed, the heating or cooling load, and the room's acoustics.
For installation in a bedroom, office, or living area, this criterion nevertheless deserves serious consideration.
Particularly noteworthy airflow control
Midea states that its wall-mounted units offer up to 100 air volume adjustment levels, allowing the fan's operation to be adjusted progressively.
For this installation in Napierville, this adjustment capability is particularly relevant.
The unit is mounted high on the wall. Depending on whether the goal is to cool the room quickly, simply maintain a stable temperature, or heat the space for several hours, the air speed and direction can be adjusted.
Proper use of the louver notably helps prevent an air current from being directed constantly toward someone sitting in the same place.
Intelligent sensor, humidity control, and several comfort modes
The MIDEA35 series shares many features with the MIDEA28 and MIDEA25 series.
The Midea brochure specifically mentions:
- Wi-Fi control;
- timer;
- sleep mode;
- silent mode;
- 8 °C heating;
- fan speed adjustment from 1% to 100%;
- the function Follow Me;
- horizontal swing;
- vertical swing;
- automatic cleaning;
- the intelligent sensor;
- humidity control;
- the optional 24 V interface;
- the optional wired controller.
These features have their uses, but some become particularly interesting depending on the type of space.
The Follow Me function
With Follow Me, the sensor located in the remote control measures the temperature near where the user is located. The system can therefore rely on this measurement rather than only on the one taken directly at the indoor unit.
In a room where the unit is installed near the ceiling, this feature can improve perceived comfort, as the temperature at occupancy level may differ from that measured higher up.
The 8 °C heating mode
The 8 °C mode is used to maintain a minimum temperature when the building remains unoccupied. According to the Midea guide, this feature is intended in particular to help prevent the home from freezing during extended absences.
For a secondary residence, cottage, or certain intermittently occupied properties, this feature can be practical.
The Wi-Fi control
The Wi-Fi control allows the air conditioning to be managed remotely from a smart device.
This notably makes it possible to adjust the temperature before returning home or check the system’s operation without being physically in front of the unit.
This Napierville project shows why a wall-mounted installation should never be improvised
Check the available space before choosing the capacity
The image of this installation shows a relatively wide unit installed beneath the ceiling.
The physical dimensions vary according to the capacity MIDEA35.
The 9,000 and 12,000 BTU models have an indoor unit measuring 37.99 in. in width, while the 18,000 BTU model reaches 44.88 in..
This difference of nearly seven inches can become decisive when working:
- between two walls;
- above a door;
- near a window;
- under a sloped ceiling;
- near a fan;
- in a room where very little wall space is available.
That is why we always check the actual room layout before confirming the final location of a wall-mounted heat pump.
The number of BTUs should not be selected based solely on floor area
A common mistake is to assume that it is enough to automatically match a number of square feet to a number of BTUs.
Floor area is only one part of the analysis.
We must also consider:
- insulation level;
- number of windows;
- sun exposure;
- ceiling height;
- room layout;
- number of floors;
- heat loss;
- use of the space;
- natural air circulation.
An oversized unit may quickly reach the desired temperature without running long enough to maintain uniform comfort.
An undersized unit may instead run continuously without being able to meet demand on the most challenging days.
Refrigerant lines vary by model
The MIDEA35 also has an important technical difference between its capacities.
For the 9,000 and 12,000 BTU models, Midea requires lines measuring 1/4 in and 3/8 in.
For the 18,000 BTU model, the lines become 3/8 in and 5/8 in.
When a heat pump replaces an older unit, we must therefore check the dimensions of the existing lines before deciding whether they can be reused.
Installing a new machine on non-compliant piping simply to avoid rerouting it is not good practice.
The electrical supply also changes
The MIDEA35 operates on 208/230 V single-phase 60 Hz.
For the outdoor unit, the indicated minimum allowable amperage is:
- 16 A for the 9,000 BTU model;
- 16 A for the 12,000 BTU model;
- 24.9 A for the 18,000 BTU model.
Midea indicates maximum protection ratings of, respectively, 20 A, 20 A, and 25 A.
These values show why the electrical panel and existing circuit must be checked before installation.
Maintenance was taken into consideration from the appliance's design stage
Midea indicates that the indoor fan wheel of the MIDEA35, MIDEA28, and MIDEA25 series can be removed to allow thorough cleaning of the unit.
This feature is valuable in the long term.
A wall-mounted heat pump moves a significant volume of air throughout its service life. Even when the filters are cleaned regularly, dust can gradually accumulate on the heat exchanger or the fan wheel.
A HVAC maintenance periodic maintenance helps preserve:
- good airflow;
- better indoor cleanliness;
- quiet operation;
- adequate drainage;
- more consistent performance.
And what subsidies are available in Quebec?
The MIDEA35 combinations presented in the brochure each have an AHRI reference number and are indicated Cold Climate V6.1.
However, the presence of a certification is not enough to automatically determine the amount of a subsidy.
Programs may change, and the criteria may depend on:
- of the exact AHRI number;
- of the installed capacity;
- of the building type;
- of the replaced system;
- of the program in effect at the time of the work;
- of the documents submitted with the application.
At AirGreen, we therefore recommend verifying the exact eligibility of the installed combination rather than relying solely on the MIDEA35 designation.
A residential warranty to be verified according to the program conditions
The Midea brochure indicates a residential 12-year limited warranty on the compressor, 12 years on parts, and 10 years on labor, subject to the applicable terms and conditions.
Registering the unit and complying with the manufacturer's conditions remain important to preserve eligibility for the applicable warranties.
What this Napierville installation says about our approach at AirGreen
On this project, the interest lies not only in the presence of a MIDEA35 on the wall.
What really matters is how the unit has been integrated into the existing space.
We had to take the ceiling, the fan, the opening beneath the unit, the necessary clearance, and the direction of the airflow into account. The final installation uses part of the wall that would otherwise have been difficult to use, without cluttering the room.
This is the logic we apply to ourheat pump installation in Napierville, Montreal, Laval, Longueuil, on the North Shore and the South Shore.
We do not simply mount a unit in the first available location. Instead, we look for a combination of:
- the correct sizing;
- the right position;
- effective air distribution;
- a feasible technical route;
- accessibility for maintenance;
- a clean visual integration;
- electrical and refrigeration compliance.
The MIDEA MIDEA35 wall-mounted heat pump installed here is designed to provide heating and cooling in a single unit, with operation down to -30 °C, efficiency of up to 33.3 SEER2, variable-speed technology and several comfort-control functions.
But this Napierville project above all reminds us of a rule we consider essential at AirGreen: The performance figures listed on a specification sheet only reach their full value when the installation itself is properly planned.
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.
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What people ask us about this kind of work
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Wall-mounted or multi-zone: how do I choose?
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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).