Transforming a constrained space into a stable, accessible technical location ready for winter
This Samsung WindFree™ MaxHeat wall-mounted heat pump installation in Boisbriand perfectly illustrates the importance of adapting every HVAC project to the building's actual architecture. The outdoor unit had to be integrated beneath a metal staircase, on a brick façade, while keeping the ground-level passage completely clear.
The photograph taken after the work shows a compact, well-structured installation. The Samsung condenser is secured to two reinforced metal wall brackets. Anti-vibration isolators are placed beneath the unit's feet, while the outdoor electrical disconnect remains accessible on the right. The heat pump is oriented toward the open part of the passage, away from the wall, allowing the fan to discharge air without an immediate obstruction.
The available space seemed suitable at first glance, but several constraints had to be analyzed before drilling into the masonry:
- the downward slope of the stairs;
- the position of the steps and structural elements;
- the height required for maintenance;
- the distance between the top of the unit and the galvanized steel;
- air discharge toward the open area;
- the strength of the brick wall;
- vibrations that could be transmitted to the building;
- water drainage during defrost cycles;
- the proximity of the electrical connection;
- the possibility of snow accumulating beneath the stairs.
Our task was to use this space efficiently without creating an installation that would be difficult to maintain or vulnerable to the winter conditions of Montreal's North Shore.
Why a wall-mounted installation was better suited than a ground-mounted unit
The passage beneath the stairs had to remain usable. A heat pump installed directly on a slab would have occupied part of the available width and would have been more exposed to impacts, leaves, snow, and objects moved near the wall.
We therefore opted for a wall-mounted installation. This configuration makes it possible to reclaim the unused vertical space beneath the stairs while protecting the outdoor unit.
The elevated bracket offers several advantages:
- it completely clears the area beneath the heat pump;
- it limits the risk of collision with a bin or maintenance equipment;
- it keeps the condenser above a normal accumulation of snow;
- it makes floor cleaning easier;
- it provides space for defrost water drainage;
- it brings the unit closer to the wall penetrations and the electrical circuit;
- it improves access to the front panel during servicing.
The height nevertheless had to remain reasonable. An installation that was too high would have made coil cleaning and the possible replacement of a component more difficult. The unit was therefore positioned to remain accessible from the ground while preserving appreciable winter clearance.
Taking advantage of the staircase’s diagonal shape
The metal staircase creates a sloping ceiling. The available height gradually decreases toward the right side of the photo. We therefore could not simply center the unit on the wall.
The condenser was placed in an area where its cabinet remains sufficiently far from the structure. The service panel, located on the connection side, remains accessible. The staircase steel touches neither the top of the unit nor the refrigeration lines.
This separation is essential. A heat pump must not vibrate against a step, stringer, or guardrail component. Intermittent contact could produce a metallic noise in the home or on the staircase, particularly when the compressor modulates its speed.
The open steps promote some vertical ventilation. However, they do not replace the clearance required in front of the fan. Air must be able to leave the front grille and disperse into the open area without being immediately pushed back toward the coil.
An orientation that protects airflow
On this Boisbriand installation, the fan faces the passage rather than the brick wall. The air discharge therefore has an unobstructed volume in front of the unit.
Poor positioning beneath a staircase can cause recirculation. The air just discharged by the condenser then returns toward its coil. In air conditioning mode, this situation increases the temperature of the air drawn into the unit. In heating mode, it can alter the conditions around the heat exchanger and interfere with normal operation.
Possible consequences include:
- longer operating cycles;
- increased power consumption;
- reduced capacity;
- accelerated fouling;
- less favorable refrigeration pressures;
- premature aging of certain components.
The space in front of the unit must therefore remain clear after installation. It should not become a storage area for bicycles, boxes, firewood, or wheeled bins.
Wall supports suitable for the appliance's load
The two brackets visible in the photo are not used solely to hold the heat pump above the ground. They must distribute the unit's weight and withstand the forces generated during operation.
Before mounting a support on a brick façade, we assess the wall construction and the condition of the masonry. A cracked brick, deteriorated joint, or fastener installed in an unsuitable area can reduce the strength of the entire assembly.
We must take into account:
- the weight of the condenser;
- the depth of the appliance;
- the spacing between its feet;
- fan movement;
- changes in compressor speed;
- wind;
- freeze-thaw cycles;
- the loads applied during servicing.
The horizontal arms must provide full support beneath the feet. The condenser must not extend dangerously beyond the support or rest on only one edge.
In this project, the vertical studs are aligned with the wall, and the diagonal braces stiffen the structure. This geometry reduces flexing and keeps the unit stable.
Clearly visible vibration isolators
We installed vibration isolators between the Samsung's feet and the metal rails. Their purpose is to limit mechanical transmission to the supports and the façade.
This precaution is especially important when a wall-mounted heat pump is installed on a wall directly connected to a bedroom, living room, or neighboring dwelling.
Vibration control nevertheless depends on the entire installation. We must also check:
- the leveling of the unit;
- the tightening of the bolts;
- the rigidity of the brackets;
- the contact between the lines and the wall;
- the securing of the wiring;
- the closure of the panels;
- the distance from the stairs.
A copper pipe pressed directly against brick can transmit a humming sound even when isolators are installed beneath the condenser. The refrigerant lines must therefore have sufficient flexibility and be protected at contact points.
An electrical disconnect that is accessible without obstructing the passage
The box installed to the right of the unit allows its power supply to be disconnected locally. Its location was chosen so that a technician can reach it without moving the condenser or dismantling the stairs.
The exposed connection remains short and protected. This prevents us from routing cables through the traffic area.
For a reliable installation, the circuit must match the values listed on the nameplate of the model actually installed. BTU capacity alone is not enough to determine the circuit breaker. We must verify, in particular:
- the minimum circuit ampacity;
- the maximum permitted protection;
- the required voltage;
- the cable type;
- grounding;
- the protection of outdoor conductors;
- the watertightness of the electrical connections.
The disconnect switch must not be located directly beneath an area where defrost water could drain.
Managing defrost water beneath the staircase
A heat pump that provides heating in winter produces water during its defrost cycles. The outdoor coil can accumulate frost when the air is cold and humid. The system temporarily reverses its operation to melt this frost.
The Samsung WindFree™ MaxHeat is designed for cold climates. Samsung states that this range can deliver its full heating performance at approximately -15 °C, maintain heat output down to approximately -30 °C, and use a built-in base pan heater to facilitate drainage and limit ice buildup in the lower pan.
The wall bracket nevertheless remains essential. It creates sufficient clearance between the unit’s base pan and the ground.
Under a staircase, water can freeze in a shaded area and form a slippery patch. The location must therefore allow water to flow away from the base without reaching an entrance, threshold, or frequently used walkway.
We recommend monitoring the space beneath the unit during periods of damp cold. Some ice on the ground may be normal, but it must not rise to the condenser or obstruct its drainage openings.
Performance, commissioning, and long-term maintenance of the Samsung WindFree™ MaxHeat
A range of capacities that must be sized according to the building
The Samsung WindFree™ MaxHeat is available in several capacities: 9,000, 12,000, 15,000, 18,000, and 24,000 BTU/h. The manufacturer publishes different performance ratings depending on the exact combination of indoor and outdoor units.
Because the nameplate is not legible in the photograph, it would be inaccurate to determine this system’s capacity solely from the dimensions of the cabinet. At AirGreen, we always confirm the capacity using the model numbers shown on the unit, invoice, and technical documentation.
For reference, the Samsung WindFree™ MaxHeat 12,000 BTU/h combination is published with efficiency ratings of up to 24.0 SEER2 in cooling and 10.5 HSPF2 in heating. The range also includes configurations reaching up to 25.0 SEER2 or 11.0 HSPF2, depending on the selected capacity.
These values do not replace a load calculation. To choose a heat pump in Boisbriand, we analyze in particular:
- the actual area served;
- the number of exterior walls;
- insulation;
- air infiltration;
- window orientation;
- solar exposure;
- ceiling height;
- the openings between rooms;
- the number of occupants;
- the existing heating system.
Two homes with the same floor area may require different capacities. A property with extensive windows or poor airtightness will require more heating than a renovated building with an efficient envelope.
Why a larger unit is not automatically better
Oversizing remains a common mistake in residential air-conditioning and heating projects. An oversized unit can quickly reach the desired temperature, reduce its operating time, and remove less humidity during the summer.
Conversely, an undersized unit may run continuously during extreme periods without being able to maintain the setpoint.
The variable-speed compressor in the WindFree™ MaxHeat can modulate output according to demand. This modulation improves temperature stability, but it does not compensate for an inappropriate initial selection.
We therefore seek a balance between:
- maximum required capacity;
- low-load modulation;
- humidity control;
- energy consumption;
- noise level;
- comfort in more distant rooms.
WindFree™ comfort on the indoor-unit side
The name WindFree™ refers to the distribution method used by the indoor wall-mounted unit. As the temperature approaches the setpoint, the unit may distribute air through numerous microperforations rather than maintaining a concentrated airflow.
Samsung indicates that the air speed in WindFree™ mode remains below 0.15 m/s, a threshold corresponding to an almost imperceptible air sensation according to the technical reference cited by the manufacturer.
This airflow is particularly suitable for installations where the indoor unit is located:
- near a sofa;
- facing a worktable;
- in a bedroom;
- in an open-plan area;
- above an area that is frequently occupied.
Indoor placement remains important. A cabinet, beam, or curtain positioned in front of the evaporator can limit airflow, even with WindFree™ technology.
The range also offers control through the SmartThings app, subject to a network connection and the required account setup. The manufacturer provides monitoring, remote adjustment, and automation features according to the parameters available on the model.
Refrigerant connections prepared to last
Behind the condenser, the refrigerant lines connect the outdoor unit to the evaporator installed in the home. Their diameter varies according to the exact capacity.
Preparing the connections requires several steps:
- cut the copper cleanly;
- remove burrs without contaminating the pipe;
- install the appropriate nuts;
- make even flares;
- align the connections without forcing the pipes;
- tighten according to the manufacturer’s requirements;
- check for leaks;
- carry out a controlled vacuum procedure.
A crushed pipe or a misaligned connection can reduce performance or cause a slow leak.
We also avoid unnecessary lengths coiled behind the unit. An excessive loop can vibrate, complicate servicing, and create a messy appearance.
The leak test and vacuum procedure
After making the connections, we must confirm that the circuit is leak-tight before commissioning.
Pressurizing with dry nitrogen makes it possible to check the connections without introducing moisture. Once the test is complete, a vacuum pump removes the air and water vapor present in the pipes.
A vacuum should not be assessed solely by its duration. The result depends on:
- of the system’s length;
- of the pipe diameter;
- of the outdoor temperature;
- of the pump’s capacity;
- of the condition of the hoses;
- of the moisture present;
- of the assembly’s tightness.
We check the level achieved and its stability after isolation. An abnormal rise may indicate a leak or residual moisture.
These operations are no longer visible when the panels are closed. However, they have a direct influence on the reliability of the compressor and the performance of the heat pump.
Checks performed at startup
The final startup includes a series of checks in heating and cooling modes.
We check in particular:
- communication between the two units;
- compressor startup;
- fan rotation;
- supply air temperature;
- operation of the louvers;
- indoor condensate drainage;
- absence of an error code;
- mechanical stability of the condenser;
- noises and vibrations;
- operation of the controls;
- response to setpoint changes.
We also check that the outdoor panel is properly closed and that no cable can come into contact with the fan or a hot surface.
Mistakes to avoid after an installation under a staircase
Future proper operation also depends on how occupants use the space.
Pile objects in front of the fan
Bins, bicycles, and materials stored under the staircase can block the air discharge.
Install a cover during the winter
A heat pump that is operating must never be covered with a full cover. The coil and fan need unobstructed airflow.
Let snow reach the base
The raised support provides significant protection, but exceptional accumulation must still be removed.
Break the ice with a metal tool
The lines, pan, and fins can be damaged by a shovel or hammer.
Aim a pressure washer at the coil
The fins are thin and can bend. Professional cleaning uses a method suited to the degree of buildup.
Modify the support to create a shelf
The brackets are sized for the heat pump. They must not support any additional loads.
Recommended maintenance for this installation in Boisbriand
The location under a staircase partially protects the condenser from direct precipitation, but it can also trap dust, leaves, and debris.
We recommend:
- inspect the coil regularly;
- remove leaves around the unit;
- keep the fan clear;
- monitor the vibration isolators;
- check the visual condition of the supports;
- keep the disconnect switch accessible;
- clean the indoor filters;
- observe defrost cycles;
- request HVAC maintenance if unusual noise or ice appears.
A blocked coil restricts airflow and forces the system to operate under less favorable conditions.
LogisVert financial assistance: verify the exact combination
A heat pump certified as ENERGY STAR® for cold climates may be eligible for the LogisVert program when the building, equipment, and work meet the applicable criteria. The amount must be verified using the model number or AHRI number in Hydro-Québec’s official tool. The application must be submitted within nine months of installation.
For certain multi-unit buildings meeting specific criteria, an enhancement available for installations completed since June 15, 2026 brings the total assistance to $220 per 1,000 BTU/h of capacity at -8 °C. This measure applies in particular to cold-climate wall-mounted heat pumps installed in eligible buildings located in designated areas.
This enhancement does not automatically apply to all properties in Boisbriand. The building type, year of construction, address, heating system, and other program criteria must be verified.
The important documents generally include:
- itemized invoice;
- indoor and outdoor models;
- AHRI or ENERGY STAR® number;
- installation date;
- proof of payment;
- serial numbers;
- photos of the rating plates.
An installation that respects the existing space
The result of this project in Boisbriand is a discreet installation that makes use of the available space beneath the staircase without obstructing traffic.
The Samsung heat pump is:
- securely fastened to the brick;
- raised for winter conditions;
- oriented toward an open space;
- mechanically isolated from the supports;
- separated from the metal structure;
- connected to an accessible disconnect switch;
- positioned to facilitate servicing;
- protected from impacts at ground level.
This configuration summarizes our approach at AirGreen. We do not simply look for a place to set the unit. We analyze airflow, noise, drainage, accessibility, and the building’s everyday use.
We apply the same level of care to our wall-mounted heat pump installations in Montreal, Laval, Longueuil, on the North Shore and on the South Shore. A space beneath a staircase, a condo balcony, a narrow yard, or a flat roof each requires a different solution.
In this project, the choice of a wall mount, the position beneath the staircase slope, and the addition of anti-vibration isolators made it possible to achieve a clean, functional HVAC installation suited to Quebec’s climate.