Installation of a Midea28 wall-mounted heat pump in Outremont
Installation of a Midea28 wall-mounted heat pump in Outremont: four-season comfort, Energy Star® efficiency and perfect integration into a heritage home by AirGreen Montréal.

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.
Modern comfort integrated into a heritage home in the heart of Outremont
At AirGreen , we recently completed a Midea28 wall-mounted heat pump installation in a charming, typical Outremont home known for its wood-paneled architecture and stained-glass windows. This project perfectly illustrates how we combine cutting-edge HVAC technology with respect for the architectural character of older Montreal homes.
A challenge of integration in a restricted space with high ceilings
The installation was carried out in a high-ceilinged stairwell , a strategic location for optimal air distribution between floors. The interior wall header was fixed at a height calculated to maximize air circulation while remaining visually discreet.
The Midea28 model , operating with R-454B refrigerant , was chosen for its exceptional performance in extreme cold (down to −30°C) and its superior energy efficiency , ideal for Montreal's harsh winters.
The Midea28: a high-performance wall-mounted heat pump adapted to the Quebec climate
-
Capacity : 12,000 BTU, suitable for an open area on two levels.
-
Efficiency : variable speed inverter technology, guaranteeing constant comfort without overconsumption.
-
Quiet operation : less than 23 dB in night mode, perfect for quiet residential spaces.
-
R-454B refrigerant : new generation with low global warming potential (GWP).
-
Eligible for grants : Éconologis and Rénoclimat programs for its Energy Star® certified performance.
A clean, safe installation that respects the original style
Our technicians paid particular attention to preserving the wooden frame and the adjacent decorative stained glass window . The refrigerant duct outlet was carefully planned to remain invisible from the main rooms. A cream-colored finishing cap was used to blend perfectly with the wall color.
The outdoor unit, meanwhile, was discreetly installed at the rear of the house, on an anti-vibration slab , guaranteeing silent operation and increased longevity.
Optimized air diffusion in landing spaces
Installing the unit at the top of the stairs allows the heat pump to simultaneously serve both the ground floor and the upper floor . This strategic positioning takes advantage of natural air convection: heat rises in winter, and coolness descends in summer. This approach maximizes comfort without requiring a second wall-mounted unit.
The advantages of an AirGreen installation
Each AirGreen project combines:
-
A tailor-made thermal study based on the building’s configuration.
-
Aesthetic planning to preserve the architectural style.
-
An installation compliant with CSA and RBQ standards .
-
Complete system calibration and pressure testing to ensure optimal performance.
Result: four-season comfort and preserved aesthetics
Thanks to this installation, the residence now benefits from uniform comfort throughout the year, without compromising on interior design. The Midea28 blends harmoniously into the environment while offering a significant reduction in energy bills .
At AirGreen , we know that every home has its own unique character. Our role is to provide the most suitable HVAC solution , combining performance, discretion and durability .
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 28 9 000 | 12,000 | 11,500 | −30 °C: 5,100 | 1.8 | 27.4 | 12.5 | – |
| Midea Série 28 12 000 | 12,000 | 11,500 | −30 °C: 5,900 | 1.8 | 25.4 | 10.5 | $1,440 |
| Midea Série 28 18 000 | 18,000 | 18,000 | −30 °C: 8,000 | 1.92 | 21.4 | 11.0 | $2,160 |
| Midea Série 28 24 000 | 22,200 | 24,200 | −30 °C: 11,900 | 2.34 | 21.0 | 13.5 | $2,664 |
| Midea Série 28 33 000 | 32,000 | 35,000 | −30 °C: 20,700 | 1.98 | 19.5 | 10.5 | $3,840 |
According to NEEP, it delivers 12,000 BTU/h at −8 °C (17 °F), as much as at 8 °C. It heats as hard in moderate cold as in mild weather.
At 8 °C, its certified maximum capacity reaches 16,000 BTU/h, 78% more than its nominal 9,000 BTU size.
According to NEEP, its certified heating capacity at −15 °C (5 °F) is 11,500 BTU/h, 128% of its nominal 9,000 BTU size. Its COP there is 1.80.
According to NEEP, it delivers 12,000 BTU/h at −8 °C (17 °F), as much as at 8 °C. It heats as hard in moderate cold as in mild weather.
At 8 °C, its certified maximum capacity reaches 16,000 BTU/h, 33% more than its nominal 12,000 BTU size.
At −30 °C, its certified minimum capacity is 2,000 BTU/h (3,800 at 8 °C). It slows down instead of cycling on and off.
According to NEEP, it delivers 18,000 BTU/h at −8 °C (17 °F), as much as at 8 °C. It heats as hard in moderate cold as in mild weather.
According to NEEP, its certified heating capacity at −15 °C (5 °F) is 18,000 BTU/h, 100% of its nominal 18,000 BTU size. Its COP there is 1.92.
According to NEEP, its COP at −15 °C is 2.34: the highest of the Série 28 line, which ranges from 1.80 to 1.98 at that temperature.
At −30 °C, its certified minimum capacity is 2,400 BTU/h (11,800 at 8 °C). It slows down instead of cycling on and off.
According to NEEP, its certified heating capacity at −15 °C (5 °F) is 24,200 BTU/h, 101% of its nominal 24,000 BTU size. Its COP there is 2.34.
According to NEEP, its certified maximum capacity at −30 °C (−22 °F) is 20,700 BTU/h, 63% of its nominal 33,000 BTU size.
At −30 °C, its certified minimum capacity is 4,200 BTU/h (19,700 at 8 °C). It slows down instead of cycling on and off.
According to NEEP, its certified heating capacity at −15 °C (5 °F) is 35,000 BTU/h, 106% of its nominal 33,000 BTU size. Its COP there is 1.98.
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).
