Installation of a FUJITSU AIRSTAGE Orion XLTH+ wall-mounted heat pump in Saint-Antoine-sur-Richelieu: compact installation above a window and heating down to -30 °C

In Saint-Antoine-sur-Richelieu, a restricted location transformed into an efficient and discreet HVAC solution

In Saint-Antoine-sur-Richelieu, we completed an installation that perfectly illustrates a common challenge in Quebec homes: finding the best possible location for a wall-mounted heat pump when a room offers little free wall space at height.

In the photograph of our installation, the indoor FUJITSU AIRSTAGE Orion XLTH+ unit is positioned directly above a large window, near the upper corner of the room. The available space was therefore limited: a relatively low ceiling, a wall return on the right, a glazed opening immediately below the unit, and connections that had to be routed neatly to the left.

Rather than viewing these constraints as a reason to choose a less favorable location, we worked with the existing architecture. The goal was to preserve the walls needed for furniture, maintain good air projection into the room, and achieve a finish that was as discreet as possible.

The photograph clearly shows the result: the white unit blends into the light-colored decor, the window remains fully functional, and the heat pump occupies an area that otherwise would have been difficult to use.

This FUJITSU heat pump installation in Saint-Antoine-sur-Richelieu also demonstrates why the quality of an HVAC installation is not measured solely by the model selected. The height, clearances, airflow direction, line routing, condensate drainage, and access for maintenance must all be considered together.

Why install a heat pump above a window?

In many homes, the space immediately above a window is one of the few areas clear enough to accommodate a wall-mounted unit.

This can be an excellent solution when the installation is properly planned.

In this project, this configuration notably allows us to:

• keep large wall surfaces available for furniture;
• avoid installing the unit at occupant height;
• take advantage of an elevated location to distribute the air;
• preserve access to the window;
• visually integrate the heat pump into an area already structured by the opening.

An installation above a window nevertheless requires carefully checking the remaining space between the top of the unit and the ceiling. An indoor unit must be able to draw in air properly and remain accessible for maintenance.

We must also take the lintel, wall structure, and line routing into account.

A heat pump should never be positioned simply because it physically “fits” in the available space.

An installation near a corner requires additional attention

In the photograph, the right end of the unit is relatively close to the wall return.

This type of situation requires precise positioning.

A unit placed too deeply in a corner may have more difficulty distributing its air evenly. We must therefore maintain the necessary clearances around the unit and ensure that the front air jet is not immediately obstructed.

The air outlet flap visible beneath the FUJITSU is wide open, making it possible to see the area through which the air is distributed.

In a configuration like the one in Saint-Antoine-sur-Richelieu, the vertical direction of the airflow is particularly important: in cooling mode, we generally seek to send cool air into the room so that it gradually mixes; in heating mode, the air must be directed in a way that counteracts its natural tendency to remain near the ceiling.

A discreet finish for the connections

Another visible detail in the photograph is located to the left of the indoor unit.

The connections are concealed by a white finish that connects the unit neatly to the wall. This protects the lines while avoiding having a highly visible mechanical installation run across the room.

For us, a wall-mounted heat pump installation must function properly, but it must also respect the interior of the home.

The refrigerant lines, communication cable, and condensate drain are all part of the system. Their routing must be considered from the outset.

Poor planning can result in a succession of trim pieces, elbows, or visible sections that could have been avoided.

In this residence in Saint-Antoine-sur-Richelieu, the proximity of the window and corner made this planning especially important.

FUJITSU Orion XLTH+: designed to heat down to -30 °C

The FUJITSU AIRSTAGE Orion XLTH+ is a single-zone wall-mounted heat pump designed for cold climates. FUJITSU technical documentation indicates a heating operating range down to -30 °C, making it particularly well suited to Quebec winters.

This feature matters just as much in Saint-Antoine-sur-Richelieu as it does in Montreal, Laval, Longueuil, on the North Shore, or on the South Shore.

We are meeting more and more homeowners who want to use their heat pump as a true heating system throughout the winter, rather than merely as an air conditioner with an auxiliary heating function.

However, the minimum operating temperature tells only part of the story.

We must also consider the capacity the machine can still deliver when it is very cold outside.

Particularly impressive heating performance in extreme cold

The FUJITSU technical data sheet presents three versions in the range: 09KTAP1, 12KTAP1, and 15KTAP1.

At -30 °C, the manufacturer indicates that their maximum heating capacity still represents 113%, 103%, and 101% of their nominal capacity, respectively. At -26 °C, these values reach 147%, 128%, and 116%.

This type of data is highly relevant when a homeowner compares two cold-climate heat pumps.

A machine may display “heating down to -30 °C” while having lost a significant portion of its capacity before reaching that temperature.

At AirGreen, we therefore seek to analyze the equipment’s actual performance under conditions corresponding to our winters.

Three available capacities in the Orion XLTH+ family

The documentation provides the following nominal specifications:

• The 09KTAP1 model provides 9,000 BTU/h in cooling and 12,000 BTU/h in heating;
• The 12KTAP1 model provides 12,000 BTU/h in cooling and 15,300 BTU/h in heating;
• The 15KTAP1 model provides 14,500 BTU/h in cooling and 17,400 BTU/h in heating.

The photograph of this installation clearly identifies a FUJITSU AIRSTAGE wall-mounted unit, but the exact capacity is not readable in the image.

We therefore do not assign it arbitrarily.

This detail is important because the number of BTUs must always be tied to the building’s actual heating load.

High seasonal efficiency depending on the model

The FUJITSU technical data sheet indicates a TRÈS2 of 33.5 for the 09KTAP1, 31.5 for the 12KTAP1, and 28.7 for the 15KTAP1. All three versions are also listed with the ENERGY STAR ratings mentioned in the documentation.

These performance figures are interesting, but the highest number does not automatically correspond to the best choice.

A heat pump must be sized according to:

• the floor area;
• the insulation level;
• the glazed area;
• window orientation;
• ceiling height;
• air infiltration;
• the layout of the rooms;
• the level at which the unit is installed;
• the desired indoor temperature.

In this installation, the large window directly below the unit is precisely one element of the thermal envelope that we need to consider.

Why the details of this FUJITSU installation matter as much as the machine’s specifications

A window can represent both a constraint and a strategic element

Glazing is generally among the surfaces in a room that respond most quickly to outdoor conditions.

In winter, a window can become a colder area than the surrounding walls. In summer, especially with significant solar exposure, it can become a source of heat gain.

Installing a heat pump above a window can therefore be appropriate, but the direction of the airflow must be adjusted.

We want to promote an even distribution of air throughout the room rather than create a short loop in which the unit mainly treats the air around it.

The FUJITSU vertical motorized louver contributes to this control.

The documentation also indicates several fan speeds as well as an automatic setting, allowing the airflow to be adjusted according to comfort needs.

Very quiet operation for a living space

The indoor unit can operate at a very low sound level.

FUJITSU indicates 23 dB(A) in quiet mode for the 09KTAP1 and 12KTAP1 models, and 26 dB(A) for the 15KTAP1.

This feature becomes especially important when a heat pump is installed in a bedroom, office, or living room.

The photo of Saint-Antoine-sur-Richelieu shows a unit integrated into a residential space, where acoustic discretion is therefore particularly important.

A heat pump used year-round operates for many more hours than an air conditioner used occasionally. Noise should therefore be considered when choosing the system.

Inverter technology: modulating output instead of constantly operating at full capacity

The FUJITSU Orion XLTH+ uses an Inverter compressor.

This technology allows the unit to adjust its output instead of operating only in full-capacity on/off cycles.

Lorsque la température intérieure approche de la consigne, l’appareil peut réduire son fonctionnement.

When the indoor temperature approaches the setpoint, the unit can reduce its operation.

When a higher load occurs, it can increase its capacity.

• This modulation notably promotes:
• a more stable temperature;
• better adaptation to load variations;
• fewer abrupt fluctuations;
• energy consumption better proportioned to actual needs.

In a room with a large window, this adaptability is particularly useful because heat gains and losses can change quickly depending on the time of day.

Integrated Wi-Fi for controlling the heat pump remotely

FUJITSU documentation also indicates integrated Wi-Fi connectivity with remote monitoring through the AIRSTAGE mobile app.

For a homeowner, this feature makes it possible to change the settings from a compatible phone.

This can be useful when leaving the house for several hours, when you want to prepare the temperature before returning, or simply when you want to adjust the unit without searching for the remote control.

The range can also support various control accessories, including certain interfaces designed for more advanced systems.

Copper ProCore coils inside

The page dedicated to the Orion XLTH+ specifications indicates that the indoor unit uses highly corrosion-resistant copper ProCore coils.

This may not be the first feature a homeowner notices on a heat pump, but this type of design contributes to the equipment’s durability.

A cold-climate heat pump can operate for much of the year: cooling in summer, heating during the shoulder seasons, and winter heating when conditions allow.

The quality of the internal components therefore becomes important over the long term.

R-32 refrigerant: a newer generation of wall-mounted systems

The series operates with R-32.

Fujitsu states in its documentation that R-32 has a global warming potential of 675, compared with 2,088 for R-410A—an advertised reduction of 68%.

R-32 is one of the technological developments we are now seeing in new HVAC equipment.

For the homeowner, this also means that the installation must be carried out using the appropriate tools, practices, and skills for the refrigerant used.

1/4 in – 3/8 in piping across the entire range

For the three Orion XLTH+ capacities, Fujitsu specifies the same refrigerant line sizes:

• 1/4 in. on the liquid line;
• 3/8 in. on the gas line.

The published minimum length is 10 feet.

The maximum length can reach 66 feet, with a maximum vertical difference of 49 feet.

These options provide good flexibility when installing in a building where the outdoor unit cannot necessarily be placed directly behind the indoor unit.

Nevertheless, we always seek the most logical and cleanest route possible.

A manufacturer's permitted maximum length is not a target to reach; it is a limit that provides flexibility when it is genuinely necessary.

Condensate drainage is particularly important above a window

In cooling mode, the indoor unit removes moisture from the air.

This water must be routed outdoors or to an appropriate drainage point.

In an installation like the one in Saint-Antoine-sur-Richelieu, located directly above a window, reliable drainage is absolutely essential.

We must avoid any possibility that a slope problem or obstruction could cause water to reach the interior finish, the window framing, or the wall.

The drain route must therefore be considered at the same time as the refrigerant piping route.

This is an excellent example of a detail that is invisible in a completed installation but fundamental to its reliability.

Access to the filters must be maintained despite the proximity of the ceiling

The unit is installed relatively high.

This saves wall space and improves air distribution, but maintenance must be considered from day one.

The filters of a wall-mounted heat pump must be cleaned periodically.

A unit installed without adequate clearance or in an area that becomes inaccessible after furniture is added can make this operation unnecessarily complicated.

At AirGreen, we want an installation to be not only neat on the day of the job, but also easy to maintain several years later.

Winter heating also depends on the quality of the outdoor installation

Although the photograph shown here mainly depicts the indoor unit, a heat pump always operates as a system that includes an outdoor unit.

Fujitsu indicates that the Orion XLTH+ features, among other things, a base pan heater designed for extremely cold climates.

During winter heating, the outdoor unit must periodically defrost its coil. The water produced must be able to drain properly.

The outdoor location must therefore be prepared for:

• snow accumulation;
• defrost cycles;
• possible ice formation;
• air circulation;
• service access;
• the required clearances.

A heat pump capable of heating down to -30 °C deserves an outdoor installation designed to operate through a true Quebec winter.

The electrical circuit varies according to the selected capacity

The Orion XLTH+ range operates at 208 to 230 V, 60 Hz, single-phase.

The technical table specifies:

• a 15 A circuit breaker for the 09KTAP1;
• a 20 A circuit breaker for the 12KTAP1;
• a 20 A circuit breaker for the 15KTAP1.

The machine selection must therefore be accompanied by an assessment of the electrical situation.

We regularly encounter homes where the available space in the electrical panel is limited. Checking this before installation helps avoid surprises during the work.

A common mistake: choosing BTUs based solely on floor area

An approximate square-footage rule is not enough to size a heat pump.

Two rooms of the same size may have completely different needs.

A room with a large window like the one shown in the photo may be more affected by outdoor conditions than an interior room without glazing.

The insulation, solar exposure, ceiling height, exterior walls, and airflow to the other rooms must also be analyzed.

We therefore prefer to select a FUJITSU heat pump according to the actual load rather than automatically choosing the largest model available.

An operating range that covers practically the entire year

The technical specifications published for the Orion XLTH+ indicate an operating range from -10 °C to 50 °C in cooling mode and from -30 °C to 24 °C in heating mode.

This wide range clearly illustrates the purpose of this heat pump: providing comfort during much of the year.

In Saint-Antoine-sur-Richelieu, it can therefore contribute to:

• heating during cold days;
• light heating during the fall and spring;
• summer air conditioning;
• reducing humidity during hot periods.

This versatility explains why we place so much importance on its positioning. A machine used almost daily must be installed in the right location from the outset.

What this installation teaches us about small available spaces

This installation in Saint-Antoine-sur-Richelieu shows that a restricted location is not necessarily a poor one.

The area above the window was limited by the ceiling and the side wall, but it still allowed the FUJITSU unit to be integrated neatly while keeping the rest of the room available.

The key is to assess all constraints before getting started:

1. clearance around the unit;
2. wall structure;
3. filter access;
4. airflow direction;
5. line-set route;
6. drain slope;
7. outdoor compressor location;
8. power supply.

It is this preparation that makes it possible to turn a complex location into a clean installation.

Our AirGreen approach in Saint-Antoine-sur-Richelieu and throughout Greater Montreal

Every home has its own particularities.

In Montreal, we often work in more compact spaces where visible ducts need to be minimized.

In Laval or on the North Shore, we encounter many homes where the outdoor location and snow become important considerations.

In Longueuil and on the South Shore, layouts vary between bungalows, two-storey homes, condos, and older properties where available wall space may be limited.

In Saint-Antoine-sur-Richelieu, the main challenge of this project was indoors: integrating the FUJITSU AIRSTAGE Orion XLTH+ above a window in a relatively tight area while maintaining a functional and visually cohesive installation.

The heat pump offers solid technical features: heating down to -30 °C, Inverter technology, R-32 refrigerant, built-in Wi-Fi, high energy efficiency, and indoor operation as quiet as 23 dB(A), depending on capacity.

Our job is then to ensure that these features genuinely benefit the homeowner.

A good machine and a good installation are not two separate matters. They form a single system.

In this Saint-Antoine-sur-Richelieu residence, the FUJITSU unit is now installed in a location where it can provide heating and cooling without taking over a wall, compromising the window, or visually weighing down the room.

This is exactly what we look for in an AirGreen installation: a high-performance HVAC system that adapts to the home rather than a home having to adapt to the system.