A MIDEA28 installed on wall-mounted brackets: a clean solution for clearing the ground and preparing the heat pump for Quebec winters
In Vaudreuil-sur-le-Lac, this installation of a MIDEA MIDEA28 wall-mounted heat pump illustrates a type of project where the final quality is reflected as much in the choice of location as in the equipment connections. In the AirGreen project photo, the outdoor unit is installed directly against the building’s foundation, beneath a red brick façade, while being raised on two metal wall-mounted brackets.
The result is especially clean: the outdoor unit does not rest on the ground, the front fan remains completely unobstructed, and the technical side of the machine remains accessible. A few inches from the unit, there is also the electrical disconnect enclosure, installed neatly on the wall and connected to the unit by a short, orderly route.
Another detail deserves attention: the lines run vertically inside a brown line-set cover matching the brick façade. Rather than having a long white line stand out against the red wall, this color allows the installation to blend in better with the existing architecture.
This is exactly the kind of detail we consider at AirGreen in an HVAC installation in Vaudreuil-sur-le-Lac : a heat pump must operate properly, but it must also be installed logically, remain accessible, and be visually consistent with the building.
Why we raised the outdoor unit
Installing a heat pump directly at ground level may seem simple, but in Quebec, this decision must take winter into account.
A heat pump used for heating draws in and expels outdoor air even when temperatures drop well below freezing. It also runs defrost cycles to remove the frost that naturally forms on its heat exchanger.
During this defrost cycle, water can drain beneath the machine.
If the outdoor unit is installed too low, several problems may arise:
- snow accumulation around the unit;
- ice beneath the condenser;
- reduced clearance needed for airflow;
- more difficult access for maintenance;
- moisture and debris around the base.
On our Vaudreuil-sur-le-Lac, so we installed the Midea on metal wall-mounted brackets, creating significant clearance beneath the unit.
This configuration is particularly noteworthy because the photo also shows a nearby basement window. We therefore had to choose the heat pump’s height and position precisely so as not to create an unnecessary obstacle in front of the opening.
Its positioning in relation to the window is never improvised
An outdoor unit must be positioned with the surrounding building in mind.
In this case, a window is located to the left of the installation. The condenser was positioned to keep the opening clear while making efficient use of the available section of wall on the right.
We must also avoid positioning an outdoor unit so that it unnecessarily directs its exhaust air toward an immediate obstruction.
The large circular grille visible on the front of the MIDEA28 must be able to discharge air freely.
Proper placement therefore takes into account:
- windows;
- doors;
- walkways;
- decks;
- property lines;
- snow accumulation;
- the access technicians need;
- the clearances specified by the manufacturer.
On an apparently simple installation like this one, a few inches can determine whether the unit will be easy or difficult to service over the next ten years.
The brown line-set cover: a small choice that makes a big difference to the final appearance
The photograph shows a long, vertical, reddish-brown raceway running up along the brick wall.
It protects and conceals the route connecting the system components.
In a ductless wall-mounted heat pump, we generally need to route the insulated refrigerant lines, communication wiring, and other necessary components between the indoor and outdoor units.
Midea aptly highlights the flexibility of this type of system: the indoor unit connects to the outdoor unit through a relatively compact passage, without requiring a network of air ducts throughout the house.
On a brick façade, we try to keep the route as straight as possible.
The line-set cover has three important functions here:
- protect the lines from weather and impacts;
- give the installation a finished appearance;
- makes the route much less visible on the building.
The color choice is particularly successful on this installation because it Vaudreuil-sur-le-Lac, since the raceway closely matches the color of the exterior siding.
Accessible electrical disconnect right next to the heat pump
To the right of the outdoor unit, the photo clearly shows an electrical disconnect enclosure.
This component electrically isolates the equipment when service or maintenance work needs to be performed.
Its location is important: it must remain accessible to the technician and be installed neatly without creating a tangle of cables around the heat pump.
On this job, the route between the disconnect switch and the unit is short, organized, and protected.
This part of the installation is less spectacular than the condenser itself, but it is essential to the quality of an HVAC project.
MIDEA28 in Vaudreuil-sur-le-Lac: five capacities, heating down to -30°C, and R-454B refrigerant
A heat pump designed for cold climates
The MIDEA28 belongs to Midea’s premium wall-mounted series.
In the technical documentation provided for this installation, it is presented as an extreme-climate heat pump, operating in heating mode down to -30 °C, using the refrigerant R-454B and bearing the certification Cold Climate V6.1 for the listed combinations. Its efficiency can reach 27.4 SEER2 and 13.5 HSPF2, depending on the selected capacity.
For a residence with Vaudreuil-sur-le-Lac, this low-temperature operation is a much more relevant criterion than simple summer cooling capacity.
A heat pump in Quebec is used during several seasons:
- cooling during hot periods;
- dehumidification;
- heating in spring and fall;
- heating during a significant part of the winter.
MIDEA28 is specifically designed to keep operating when temperatures drop very low.
The five MIDEA28 capacities
Unlike a product line offered in only two or three sizes, MIDEA28 covers a fairly broad range of capacities.
The brochure lists five combinations.
MIDEA28 9,000 BTU
The combination includes:
- indoor unit MSEHU-H09B-2A;
- outdoor unit MO1HS-H09B-2A;
- AHRI number 215471380;
- rated cooling: 9,000 BTU/h;
- rated heating: 12,000 BTU/h;
- SEER2: 27,4;
- HSPF2 IV: 12,5.
MIDEA28 12,000 BTU
The combination MSEHU-H12B-2A / MO1HS-H12B-2A, AHRI reference 215471381, offers:
- 12,000 BTU/h in cooling;
- 12,000 BTU/h in heating;
- 25.4 SEER2;
- 10.5 HSPF2 IV.
MIDEA28 18,000 BTU
The combination MSEHU-H18B-2A / MO1HS-H18B-2A has AHRI number 215471382 and provides:
- 18,000 BTU/h in cooling;
- 18,000 BTU/h in heating;
- 21.4 SEER2;
- 11.0 HSPF2 IV.
MIDEA28 24,000 BTU
The combination MSEHU-H24B-2A / MO1HS-H24B-2A, AHRI 215471383, is rated for:
- 24,000 BTU/h in cooling;
- 29,000 BTU/h in heating;
- 21.0 SEER2;
- 13.5 HSPF2 IV.
MIDEA28 33,000 BTU
Finally, the combination MSEHU-H33B-2A / MO1HS-H33B-2A, AHRI number 215471384, offers:
- 33,000 BTU/h in cooling;
- 36,000 BTU/h in heating;
- 19.5 SEER2;
- 10.5 HSPF2 IV.
The photo of our installation does not show the complete rating plate number clearly enough. We therefore do not arbitrarily assign it an exact capacity.
This is important: MIDEA28 refers to a series, not a single capacity.
Why the model with the highest SEER2 is not automatically the right choice
The maximum efficiency of 27.4 SEER2 belongs to the 9,000 BTU combination.
This does not mean that everyone should select this capacity.
A heat pump must first meet the heating and cooling needs of the room or dwelling.
At AirGreen, sizing may take into account, among other factors:
- floor area;
- insulation;
- windows;
- sun exposure;
- ceiling height;
- the number of exterior walls;
- the room configuration;
- winter heat loss.
An undersized unit may operate constantly at high capacity.
An excessively large unit may, in turn, be less suited to the building's actual behavior.
The goal, therefore, is to choose the right capacity, rather than simply choosing the smallest one to achieve the highest SEER2 or the largest one to provide more BTUs.
Variable-speed technology changes how the machine operates
Midea uses variable-speed compressor technology.
The principle differs from that of an older air conditioner that essentially operates at full capacity and then shuts off completely.
When demand decreases, the system can reduce its output to maintain the temperature more gradually.
Midea documentation indicates that this modulation reduces temperature fluctuations and improves comfort stability compared with conventional on-off systems.
This becomes particularly interesting during long periods of heating or cooling when the building requires only a fraction of the maximum capacity.
How the MIDEA28 performs at -15 °C
To assess a heat pump intended for Quebec, we like to look beyond its minimum operating temperature.
The MIDEA28 is rated for heating down to -30 °C, but the brochure also provides its rated capacities at -15 °C.
At this temperature:
- the 9,000 BTU unit delivers 11,500 BTU/h;
- the 12,000 BTU unit delivers 11,500 BTU/h;
- the 18,000 BTU unit delivers 18,000 BTU/h;
- the 24,000 BTU unit delivers 24,200 BTU/h;
- the 33,000 BTU unit delivers 35,000 BTU/h.
The published COPs are 1.80, 1.80, 1.92, 2.34, and 1.98, respectively.
This type of information allows for a much more meaningful comparison of two heat pumps intended for winter heating.
An operating range suited to Quebec's temperature variations
For the five MIDEA28 models presented in the brochure, the manufacturer states:
- cooling: -30 °C to 50 °C;
- heating: -30 °C to 24 °C.
The low-temperature cooling range may also be of interest for certain specific applications where a room must be cooled even when the outdoor temperature is low.
For a conventional home, it is primarily the heating range that draws our attention.
R-454B: a new generation of heat pumps
The MIDEA28 uses R-454B refrigerant, in the A2L category.
The brochure also presents an A2L refrigerant leak detection sensor and various features suited to the new generations of systems.
For the installer, this involves using appropriate procedures, methods, and equipment.
When a homeowner replaces an old heat pump, we therefore carefully inspect the entire circuit rather than considering the new unit interchangeable with the old one.
Refrigerant lines vary enormously between 9,000 and 33,000 BTU
The MIDEA28 provides an excellent example of why diameters must be checked before reusing existing piping.
Depending on capacity:
- 9,000 BTU: 1/4 in and 3/8 in;
- 12,000 BTU: 1/4 in and 3/8 in;
- 18,000 BTU: 1/4 in and 1/2 in;
- 24,000 BTU: 3/8 in and 5/8 in;
- 33,000 BTU: 3/8 in and 3/4 in.
The published maximum lengths range from 82 ft for the smaller capacities to 164 ft for the 24,000 and 33,000 BTU versions.
It would therefore be technically incorrect to claim that an old line can necessarily be reused solely because both the old and new systems are called “wall-mounted heat pumps.”
Same principle for the electrical system
All the MIDEA28 units listed operate at 208/230 V, single-phase, 60 Hz, but their electrical requirements change significantly.
The minimum allowable ampacity is indicated as:
- 15 A for the 9,000 BTU unit;
- 15 A for the 12,000 BTU unit;
- 19 A for the 18,000 BTU unit;
- 24.9 A for the 24,000 BTU unit;
- 34 A for the 33,000 BTU unit.
The corresponding maximum protections are 15, 15, 20, 25, and 35 A.
The disconnect visible beside our Vaudreuil-sur-le-Lac installation is therefore part of an electrical assembly that must be selected according to the exact combination installed.
The wall bracket must also match the actual weight of the unit
Another important difference between capacities is weight.
The MIDEA28 outdoor units shown in the brochure range from approximately 72.75 lb for the 9,000 BTU version up to 156.97 lb for the 33,000 BTU model.
The choice and anchoring of the wall bracket are therefore far from trivial.
We must take into account:
- weight;
- wall structure;
- height;
- vibrations;
- stability;
- of future access to the unit.
In the photo, the Midea rests on two triangulated metal brackets that securely hold the unit above ground level.
Future maintenance made easier by an accessible location
A good job site must not become a nightmare during the first service call.
The outdoor unit in Vaudreuil-sur-le-Lac is positioned so that its service side remains accessible.
This will eventually make it possible to:
- inspect the connections;
- access the service valves;
- check the electrical components;
- clean the heat exchanger;
- check the fan;
- take operating measurements.
Inside, Midea also indicates a removable blower wheel for the MIDEA35, 28, and 25 series to facilitate deep cleaning of the wall-mounted unit.
TheHVAC maintenance must always be part of the planning at the time of installation, not several years later.
Wi-Fi functions, quiet mode, and airflow control
The MIDEA28 includes a long list of comfort features.
The brochure specifically mentions:
- Wi-Fi control;
- ECO mode;
- night mode;
- timer;
- “Follow Me”;
- automatic cleaning;
- silent mode;
- heating at 8 °C;
- horizontal and vertical swing;
- humidity control;
- optional wired controller;
- variable fan control.
Midea also announces up to 100 air-volume adjustment levels and remote control through the SmartHome app in compatible configurations.
These functions allow the heat pump to operate much more precisely than an older wall-mounted air conditioner limited to just a few speeds.
Subsidies: the AHRI number must always be confirmed
The five MIDEA28 combinations in this brochure bear the AHRI numbers 215471380, 215471381, 215471382, 215471383 and 215471384, with the mention Cold Climate V6.1.
For any request for a LogisVert subsidy or another program, we nevertheless recommend confirming the eligibility of the specific combination at the time of installation.
A commercial product line must never be used on its own to assume a subsidy amount.
The exact AHRI number, the type of building, and the program conditions are decisive.
An installation where the visible details tell the story of the work performed
This project in Vaudreuil-sur-le-Lac looks particularly simple once completed: a Midea against the wall, a bracket, a trim piece, and a disconnect.
But each of these elements reflects a specific decision.
We had to take into account the basement window, determine the unit's height, keep the fan clear, create enough space beneath the unit, neatly organize the electrical supply, and integrate the lines into the brick façade.
The brown line-set cover makes the vertical run unobtrusive. The wall bracket keeps the unit off the ground and away from winter accumulations. The disconnect remains accessible. The connections are located on the side where they can still be serviced.
This is the type of installation we strive to carry out at AirGreen on our projects in Vaudreuil-sur-le-Lac, Montréal, Laval, Longueuil, on the North Shore and the South Shore.
A MIDEA MIDEA28 can offer excellent technical features: heating operation down to -30 °C, variable-speed technology, R-454B, high efficiency, and several capacities suited to different needs.
But these qualities can never compensate for a poor location or a makeshift installation.
The role of an HVAC contractor is precisely to make all these elements work together the choice of unit, its sizing, the piping, the electrical work, the support, and the existing building.
This Vaudreuil-sur-le-Lac installation is a good example: visually relatively compact, but designed down to the details that will influence its operation for years.