Two outdoor units precisely integrated into a brick façade above a basement window
This wall-mounted heat pump installation at Ville Mont-Royal required much more than simply choosing a location on an exterior wall. The building’s layout imposed several simultaneous constraints: a brick façade, a foundation covered with render, a basement window directly below the work area, a wooden terrace, and limited space between the various architectural elements.
We installed two Samsung WindFree™ MaxHeat outdoor units on independent wall brackets. The unit on the left uses a wider chassis, while the one on the right has a more compact design. This difference in size reflects two distinct heating and cooling needs in the building, with each system selected according to the indoor zone it had to heat and cool.
The photograph also shows the actual site conditions: ladders were needed to work on the façade, the terrace had to remain usable, and the units had to be positioned without blocking the window at the lower level. The result is a structured, accessible HVAC installation suited to Montreal-area winters.
Why two independent heat pumps were chosen
Two separate outdoor units indicate the presence of two autonomous systems here. This configuration makes it possible to control the areas served separately rather than imposing a single temperature throughout the building.
Choosing two independent heat pumps can be particularly relevant when:
- The rooms are located on different floors;
- Heating needs vary from one zone to another;
- One part of the building receives more sunlight;
- Occupants use the spaces at different times;
- The interior layout limits the natural circulation of air;
- Each dwelling or floor must retain its own control.
At Ville Mont-Royal, many properties have interior divisions, additions, or levels with uneven heating and cooling loads. A single indoor unit placed in a hallway or living room cannot always distribute air effectively to enclosed rooms.
With two systems, it becomes possible to maintain a comfortable temperature in the first zone without unnecessarily running the second. This autonomy also improves flexibility of use: one unit can operate in cooling or heating mode while the other remains off.
A layout designed around the basement window
The window visible beneath the unit on the left was one of the main constraints. We had to preserve access to it while keeping the heat pumps high enough to protect them from snow and ice accumulation.
An unit placed too low could have:
- block part of the window;
- make opening or replacing it more difficult;
- receive more splashes and debris;
- be surrounded by compacted snow;
- drain defrost water too close to the frame;
- reduce the space available on the deck.
Conversely, an excessively high installation would have made maintenance, heat exchanger cleaning, and work on the electrical or refrigeration panels more difficult.
We therefore positioned the supports at a height that keeps the area above the window clear while keeping the appliances accessible with the appropriate equipment. This planning is essential in a wall-mounted heat pump installation in Montreal, where snow on the ground and freeze-thaw cycles must be considered from the outset.
Independent wall supports for each outdoor unit
Each heat pump rests on its own set of metal supports. This method makes it possible to precisely adapt the position of each appliance to its weight, size, and available space.
The supports were fastened to the foundation section rather than placed directly on the deck. This solution offers several advantages:
- it frees up the walking surface;
- it avoids adding a permanent load to the boards;
- it protects the appliances from wood movement;
- it limits contact with snow and leaves;
- it makes inspection beneath the units easier;
- it allows defrost water to drain beneath the appliances.
An outdoor deck can shift slightly with humidity, seasonal changes, and the aging of the wood. A heat pump placed on a structure that deforms can lose its level, transmit vibrations, or put stress on the refrigerant connections.
By fastening the supports to a suitable part of the building, we obtain a more stable base that is better suited to the equipment’s lifespan.
Anti-vibration pads visible beneath the appliances
The feet of both units rest on anti-vibration isolators. These components, visible in blue beneath the appliances, create a separation between the heat pump chassis and the metal support.
They help to:
- reduce vibrations transmitted to the building;
- limit resonance noise indoors;
- stabilize the units;
- protect the support points;
- absorb some of the vibrations produced by the compressor.
This precaution is particularly important when a heat pump is installed near a bedroom, living room, or neighboring dwelling. An outdoor unit may be relatively quiet in open air, but inadequate mounting can turn the wall into a resonating surface.
Two units placed close together without creating an airflow conflict
The space between the outdoor units had to be carefully planned. Each heat pump draws air through its coil and discharges it through its front grille. If two units are installed too close to each other or surrounded by obstacles, their airflow may be disrupted.
On this site, the front grilles remain completely unobstructed. No screen, deck panel, or closed guardrail is located directly in front of the fans.
We also took into account:
- the side wall on the right;
- the clearance behind the coils;
- the space between the two units;
- access to the service panels;
- the possibility of cleaning the coils;
- the movement of the discharged warm or cold air.
Airflow must never be assessed only when the system is operating in cooling mode. In heating mode, the outdoor coil becomes cold and the unit must periodically perform defrost cycles. Poor placement can promote ice formation and reduce efficiency.
An installation beneath a brick façade without compromising the building envelope
The building features a combination of red brick on the upper level and a parged foundation on the lower portion. The refrigerant lines and wiring had to be routed without unnecessarily damaging the masonry or creating penetrations that would be difficult to seal.
When installing on this type of building, we must check:
- the location of the mortar joints;
- the wall thickness;
- the possible presence of wires or pipes;
- the slope of the passage toward the outside;
- the seal around the lines;
- the protection of the refrigerant insulation;
- the condensate drain route.
An improperly sealed wall penetration can allow air, water, or insects to enter. It can also create a cold zone around the lines during winter. We therefore use a sealing method suited to the material encountered and the type of connection.
A height that allows for defrost water
During winter operation, a heat pump extracts heat from the outdoor air. Frost may then form on the coil, and the unit periodically initiates a defrost cycle.
The water produced must be able to drain beneath the outdoor unit without:
- form a block of ice around the base;
- fall onto the window frame;
- accumulate on a used walkway;
- damage the deck;
- block the lower openings of the unit.
The Samsung WindFree MaxHeat range is designed for cold climates and includes a lower pan heater intended to promote water drainage and reduce ice buildup. Samsung also claims heating capacity maintained at 100% at -15 °C and heating operation down to -30 °C, depending on the selected combination.
Even with a heater pan, the space beneath the unit remains essential. No internal device can compensate for a heat pump buried in snow or installed above a surface where water cannot drain.
Performance, WindFree comfort, and eligibility for financial incentives
A range suited to various heating needs
The Samsung WindFree™ MaxHeat series is available in several capacities, including 9,000, 12,000, 15,000, 18,000, and 24,000 BTU. Performance varies according to the exact combination of the indoor unit and outdoor unit. Samsung publishes SEER2 values of up to 25 for certain sizes, with HSPF2 values reaching 11 depending on the capacity.
However, the difference in size between the two units visible in the photograph is not, on its own, enough to identify their exact capacity. At AirGreen, we never determine a heat pump's BTU capacity solely by observing its casing.
To confirm an installation's specifications, we use:
- the complete outdoor-unit number;
- the indoor-unit number;
- the AHRI-certified combination;
- the manufacturer's performance data;
- the recognized heating capacity at low temperatures.
This verification is particularly important for rebate applications. Two units bearing the same commercial brand may qualify for different financial assistance amounts.
How WindFree air distribution works
Samsung WindFree indoor units use a front panel with numerous micro-perforations. Once the room temperature has approached the setpoint, the unit can distribute conditioned air through these openings instead of maintaining a direct jet through the large louver.
Samsung states that the air speed in WindFree mode remains below 0.15 metres per second, a level associated with a sensation of virtually still air.
This method is useful in rooms where occupants are near the indoor unit, particularly:
- a bedroom;
- an office;
- a living room;
- a dining room;
- a compact-sized home.
The system can first use more direct airflow to reach the requested temperature, then switch to gentler air distribution to maintain it. WindFree mode therefore does not replace proper sizing or careful indoor-unit placement.
Smart control and energy consumption management
The range can be controlled with the SmartThings app, which can be used to adjust settings, check the equipment’s operation, and monitor certain consumption data. Available features depend on the model, configuration, and network connection.
For this connectivity to be genuinely useful, we explain to the customer which settings have the greatest impact on performance:
- avoid constant setpoint changes;
- maintain a reasonably stable temperature;
- clean the filters regularly;
- do not block the indoor unit with furniture;
- use modulation rather than continuously shutting the system off;
- keep supplemental heating available when required.
A variable-capacity compressor heat pump is generally more efficient when it can modulate its capacity for extended periods rather than constantly alternating between full shutdown and maximum output.
LogisVert: the AHRI number must be verified for each system
An efficient heat pump may qualify for Hydro-Québec’s LogisVert financial assistance. For installations completed on or after November 26, 2025, Hydro-Québec requires eligible heat pumps to be ENERGY STAR certified.
The regular incentive applicable to a cold-climate heat pump is calculated at $120 per 1,000 BTU/h of heating capacity at -8 °C. The amount therefore does not simply depend on the nominal capacity used in the equipment’s commercial name.
For this two-system installation, each combination must be searched separately using its AHRI number or its indoor and outdoor model numbers. Hydro-Québec’s search tool makes it possible to assess the amount associated with each heat pump, and the application must be submitted within nine months of the installation date.
Possible bonus for certain multi-unit buildings
Since June 15, 2026, certain eligible multi-unit buildings may receive a bonus bringing the total rate to $220 per 1,000 BTU/h at -8 °C for a cold-climate wall-mounted heat pump.
This bonus is not automatic. In particular, the building must meet several criteria concerning its construction year, number of dwelling units, location, assessed value, and electricity billing method.
For a project in Ville Mont-Royal, we recommend confirming the criteria before calculating an amount for the budget. The municipal address and property type may directly affect eligibility.
Mistakes to avoid when installing two outdoor units
Determining capacity from chassis size
A larger cabinet does not provide sufficient information about low-temperature performance. The model number and AHRI certificate should always be consulted.
Installing both units at the same height without considering the building
Visual alignment is important, but the windows, service panels, and routing of the lines may require a slight offset.
Attaching the supports only to the cladding
Brick, stucco, or siding do not always provide suitable anchoring points. The fasteners must match the structure and the unit’s actual weight.
Forgetting vibrations transmitted to the wall
The isolators beneath the feet reduce vibrations, but the supports must also be rigid, level, and properly tightened.
Placing a unit too close to the corner
The adjacent wall may limit air intake and make access to the side panel more difficult. The manufacturer’s clearances must be checked before drilling.
Neglecting the terrace beneath the units
Defrost water, ice, and access to the basement must be taken into account. A completed installation must not create a hazard on a passage used by occupants.
Future maintenance was considered from the outset
A compact installation must remain accessible. Our team must be able to remove the panels, clean the heat exchangers, and check the connections without dismantling the other heat pump.
The HVAC maintenance of these units includes, among other things:
- cleaning the outdoor heat exchangers;
- removing leaves and debris;
- inspecting the supports;
- checking the isolators;
- checking the refrigerant lines;
- inspecting the wires;
- checking drainage beneath the units;
- thorough cleaning of the indoor units when required.
In winter, the owner must also avoid shovelling snow directly against the units. After a storm, the area in front of and beneath each unit must remain clear without using tools that could damage the heat exchanger.
An Installation Adapted to Ville Mont-Royal’s Architecture
This project demonstrates that it is possible to integrate two Samsung WindFree MaxHeat wall-mounted heat pumps into a residential façade without blocking openings or overcrowding the terrace.
Our work preserved:
- access to the basement window;
- a walkway on the terrace;
- adequate ventilation in front of both units;
- a height suited to winter conditions;
- independent, stable supports;
- vibration isolation;
- reasonable access for maintenance;
- an arrangement consistent with the brick façade.
At AirGreen, we carry out similar projects in Mont-Royal, Montreal, Laval, Longueuil, the North Shore, and the South Shore. Each installation is planned according to the building’s actual dimensions, heat loss, exterior structure, windows, site access, and long-term service requirements.