A wall-mounted installation where every inch counted to integrate the heat pump neatly into the existing decor
At Saint-Antoine-sur-Richelieu, we installed a Fujitsu AIRSTAGE Altair 500 wall-mounted heat pump in a room with a particularly interesting interior layout: a small horizontal window, a relatively low ceiling, two-tone wall finishes, and a large brick fireplace located immediately to the right of the installation area.
The photo of this installation clearly illustrates the challenge. The indoor unit had to be positioned high enough to clear the window, far enough from the fireplace to maintain a logical installation, and sufficiently centered to distribute air effectively throughout the room. We also had to preserve a clean appearance without making a wall already visually structured by the brick, window frame, lower paneling, and mouldings feel too heavy.
The result is a compact, clean installation: the Fujitsu heat pump is perfectly integrated above the window, with its air-distribution louver completely unobstructed and sufficient space around the unit to allow for operation and maintenance.
This type of project reflects how we work at AirGreen: we are not simply looking for a place where the machine will fit. We look for the location that offers the best compromise between performance, air distribution, technical access, and visual finish.
Why the location above the window made sense
In a room like this, several wall surfaces may appear available at first glance, but not all of them are necessarily suitable for a wall-mounted unit.
The fireplace occupies a large portion of the right-hand wall. It also creates a particular thermal zone that must be considered when choosing the location of a heat pump. Installing the unit too close to a heat source can distort the local perception of temperature and interfere with comfort control.
On the left, the window limits the available space at intermediate height.
The location selected above this window therefore preserves the functional wall while positioning the indoor unit high enough to ensure good air projection.
This position offers several advantages:
- it completely frees up the living space;
- it avoids interfering with the brick fireplace;
- it allows conditioned or heated air to circulate throughout the room;
- it keeps the unit easily accessible for filter cleaning;
- it creates a much more natural visual integration than an off-center installation.
On a residential project, this kind of detail makes a real difference in the final result.
A heat pump installed in a room with a fireplace: what to consider
The presence of a fireplace is an important consideration in a comfort assessment.
Even when the fireplace is not used continuously, it can generate considerable localized heat when operating. A heat pump placed too close to or directly above a strong heat source could respond to a temperature that does not represent the rest of the room.
In this installation in Saint-Antoine-sur-Richelieu, the Fujitsu wall-mounted unit is positioned on the adjacent wall, at a reasonable distance from the fireplace.
This helps maintain a more representative reading of the ambient temperature and distribute the air more effectively throughout the space.
The photo also shows that the unit’s air outlet is completely unobstructed. No furniture, shelf, or architectural element blocks the lower louver.
This is essential because a wall-mounted unit operates primarily through its airflow. Poor air distribution can create cold or hot zones even when the unit’s capacity is correct.
Fujitsu AIRSTAGE Altair 500: a range of R-32 Inverter wall-mounted heat pumps
Multiple capacities to adapt the system to the building
The Fujitsu AIRSTAGE Altair 500 is part of Fujitsu’s single-zone H series. The technical documentation provided lists six capacities: 09KPAS1, 12KPAS1, 18KPAS1, 24KPAS1, 30KPAS1, and 36KPAS1.
The advertised nominal cooling capacities are:
- 9,000 BTU/h;
- 12,000 BTU/h;
- 18,000 BTU/h;
- 22,000 BTU/h;
- 30,000 BTU/h;
- 33,000 BTU/h.
In heating mode, the nominal capacities are 10,000, 14,000, 18,000, 24,000, 30,000, and 34,000 BTU/h, respectively.
The exact capacity of the photographed unit is not legible in the interior image. We therefore avoid arbitrarily assigning a BTU rating to this installation.
In practice, the choice between 9,000, 12,000, 18,000 BTU or more depends on the building itself: floor area, insulation, sun exposure, windows, ceiling height, adjacent rooms, and overall heat distribution.
Inverter modulation that helps maintain a more stable temperature
The Altair 500 series uses an Inverter compressor.
Rather than operating only at full capacity and then stopping, the system can modulate its output within a given range.
For example, the Fujitsu data sheet indicates that the 12,000 BTU model can modulate in cooling between 3,100 and 13,600 BTU/h, then in heating between 2,700 and 17,000 BTU/h. The 18,000 BTU model has a range of 4,000 to 20,000 BTU/h in cooling and 4,150 to 24,000 BTU/h in heating.
This modulation is particularly beneficial in a room like the one shown here.
When the fireplace is operating, for example, the heat pump's heating needs may decrease quickly. When it is off, the heating load may rise again. The modulation capacity allows the system to adjust more gradually to these changes.
Particularly quiet indoor operation depending on capacity
In a relaxation room or living room with a fireplace, operating noise becomes an important consideration.
Fujitsu indicates an indoor sound level as low as 19 dB(A) in quiet mode for the 9,000 and 12,000 BTU models. The 18,000 BTU model reaches 26 dB(A), while higher-capacity models naturally produce greater airflow.
Each unit has six fan speeds plus automatic mode.
This modulation allows the system to operate at a very low airflow when demand is low, then increase circulation when the room requires more heating or cooling.
In a space like Saint-Antoine-sur-Richelieu, where the unit is clearly visible and relatively close to the occupied area, this acoustic comfort becomes particularly important.
R-32: a new generation of refrigerant for this series
The Altair 500 series uses R-32 refrigerant.
In its documentation, Fujitsu compares the global warming potential of R-32, rated at 675, with that of R-410A, listed at 2088. This represents a reported 68% reduction in GWP.
The manufacturer also emphasizes that systems using R-32 require less refrigerant while maintaining their heating performance.
For homeowners replacing an older wall-mounted heat pump, this change means that it is not enough to compare only the number of BTUs or the price.
The refrigerant type, connections, piping, and installation practices must also be taken into account.
Up to 26.0 TRÈS2 depending on the model selected
Energy efficiency varies by capacity.
The series documentation lists the following TRÈS2 values:
- 26.0 for the 9,000 BTU;
- 24.0 for the 12,000 BTU;
- 22.0 for the 18,000 BTU;
- 21.5 for the 24,000 BTU;
- 22.0 for the 30,000 BTU;
- 21.0 for the 36,000 BTU.
The CPSC2 values for region V range from 7.7 to 8.3 depending on capacity.
These figures make it possible to objectively compare the range’s energy performance, but a project’s actual efficiency also depends on the quality of the installation.
A poorly positioned or improperly sized unit, or one whose filters are constantly clogged, cannot deliver the same results as a properly selected and maintained system.
Official Heating Down to -15 °C
The Fujitsu technical specifications indicate a heating operating range down to -15 °C for Altair 500 models.
For homeowners in Saint-Antoine-sur-Richelieu, this information must be considered in the context of Quebec winters.
The heat pump can provide a significant portion of seasonal heating, but the building’s behavior must be properly anticipated when the outdoor temperature falls below the stated limit.
This is particularly relevant when a home also uses another heating source, such as a fireplace.
A good comfort strategy involves understanding the role of each system rather than simply running them without coordination.
A Compact Indoor Unit That Fits Easily into Tight Spaces
The photo of this installation shows one of the range’s most tangible advantages: its relatively compact wall-mounted form factor.
Depending on capacity, the indoor units are approximately 834 mm to 1,150 mm wide. The 9,000 and 12,000 BTU models, for example, are listed as approximately 834 mm wide, 270 mm high, and 222 mm deep.
This type of layout makes it possible to install a heat pump in areas where available wall space is limited.
In our project, the location above the window is a good example. The available height between the frame and the ceiling was not immense, but it was generous enough to create a clean installation.
The ProCore Coils and Hydro Fin Treatment
Fujitsu also highlights the ProCore copper coils, designed to provide increased corrosion resistance.
The documentation also mentions a heat exchanger with Hydro Fin fins to improve durability.
These components are less visible to the homeowner than the unit’s exterior appearance, but they play an important role in the system’s longevity.
An HVAC unit is not simply a wall-mounted box: behind the front panel are heat exchangers that must maintain good heat-transfer capacity for many years.
Remote Control, Wi-Fi, and Control Options
The Altair 500 comes with a backlit wireless remote control.
The range can also accommodate various control options, including a Wi-Fi adapter compatible with the AIRSTAGE Mobile app, several wired controllers, and certain interfaces compatible with BACnet or Modbus.
In a standard residence, the owner will mainly want simple operation: temperature, operating mode, ventilation, and scheduling.
However, this broader compatibility also makes it possible to integrate the system into certain more complex projects.
Why the position of the indoor unit directly affects comfort
When installing a wall-mounted heat pump, we pay particular attention to the airflow path.
Cold air in cooling mode naturally tends to descend. Warm air, on the other hand, rises.
The unit must therefore be positioned and adjusted so that it projects its airflow far enough into the room to promote uniform air mixing.
In the Saint-Antoine-sur-Richelieu installation, the elevated positioning helps take advantage of this projection.
The lower louver can direct the airflow into the room rather than straight toward a piece of furniture or a structure.
This is a decisive detail. A heat pump installed at the wrong angle may seem undersized simply because the air is not circulating properly.
Avoid installing the unit too close to the ceiling
Another common mistake is trying to position the indoor unit as high as possible.
This is not always desirable.
The necessary clearance must be maintained above the unit so that air can enter properly through the upper section and to allow for normal maintenance.
In the photo, we can see that the unit is installed near the ceiling while maintaining visible space between the two.
This clearance is important for air intake and access to the filters and components.
Simple maintenance that should not be neglected
The Fujitsu Altair 500 filters are washable.
In a room containing a fireplace, filter maintenance deserves particular attention.
Even with a well-maintained fireplace, the amount of dust and particles in the environment may vary depending on how the room is used. A loaded filter reduces airflow and may impair heat pump performance.
We therefore recommend regularly inspecting the filters visually, particularly during periods of heavy use.
Cleaning remains simple: the main thing is not to wait until a noticeable drop in airflow or performance occurs before taking action.
Pipe dimensions vary by model
Since not all Altair 500 capacities use the same piping, the exact machine model must be known before preparing the refrigerant line route.
The 9,000 and 12,000 BTU models use a gas line of 3/8 po and a liquid line of 1/4 po.
The 18,000 and 24,000 BTU models use a gas line of 1/2 po with a liquid line of 1/4 po.
The 30,000 and 36,000 BTU models use a gas line of 5/8 po and liquid 3/8 po.
That is why we always check the exact model before determining whether existing piping can be retained during a replacement.
The electrical supply also depends on the capacity
The series operates on a 208 to 230 V, 60 Hz, single-phase power supply.
The 9,000, 12,000, and 18,000 BTU models are specified with a 15 A circuit breaker. The 24,000 BTU model uses 20 A, while the 30,000 and 36,000 BTU models are specified at 30 A.
These details may sometimes seem secondary when a homeowner is shopping for a heat pump, but they become very concrete on installation day.
The electrical panel, available circuit, and model requirements must all be checked before commissioning.
A discreet installation in a room with a strong architectural character
One of the most successful aspects of this installation is its visual integration.
The room already has several strong elements: red brick fireplace, fireplace mantel, vertical paneling, trim, and a small horizontal window.
Adding a wall-mounted heat pump could easily have overwhelmed the wall.
Instead, we placed the unit in the most logical location, above the window, with a white finish that blends naturally into the upper part of the wall and the ceiling.
The unit remains visible, like any wall-mounted heat pump, but it does not dominate the room.
This is often the best result we seek: an accessible, high-performing machine that blends into the space rather than visually clashing with the interior.
This project clearly illustrates our approach at AirGreen
An HVAC installation in Saint-Antoine-sur-Richelieu can present challenges that are very different from a project in Montreal, Laval, Longueuil, on the North Shore, or elsewhere on the South Shore.
Sometimes, the main challenge is the outdoor unit. Sometimes, it is the piping. Here, the most interesting aspect was clearly positioning the indoor unit on a wall already occupied by several architectural elements.
We had to take the window, ceiling, fireplace, and air-distribution axis into account.
The result shows that a good installation does not depend solely on the quality of the heat pump selected.
The Fujitsu AIRSTAGE Altair 500 provides Inverter technology, R-32 operation, low noise levels depending on capacity, and strong efficiency ratings.
Our role is to ensure that all these qualities can actually be put to use in the building.
It is this combination of system selection, building knowledge, and installation precision that allows us to complete clean, durable projects that fit seamlessly into the occupants’ daily lives.