A particularly clean outdoor installation on a brick wall, designed for Quebec winters
In Chambly, we completed this installation of a Fujitsu AIRSTAGE Altair 500 wall-mounted heat pump in an outdoor configuration that required as much mechanical precision as aesthetic care. The result visible in the photo effectively summarizes our approach at AirGreen: a securely elevated outdoor unit, neatly grouped connections, a location that preserves the yard, and an installation that remains accessible for future maintenance.
The Fujitsu AIRSTAGE outdoor unit was secured to a robust metal wall bracket installed directly on the foundation section beneath the brick siding. It therefore rests neither on the soil nor on a low slab. This decision is particularly relevant for a heat pump intended to operate in Quebec winters, where snow, ice, and water from defrost cycles must be considered from the outset of the installation.
The photo also shows an important technical detail: the refrigerant and electrical lines enter from the right side of the unit and are grouped in an insulated black conduit. The entire assembly follows a short route between the house and the compressor. This avoids unnecessary piping loops and maintains a compact exterior finish.
The Fujitsu Altair 500 is a single-zone lineup in the H series, comprising models 09KPAS1, 12KPAS1, 18KPAS1, 24KPAS1, 30KPAS1, and 36KPAS1. Fujitsu specifies heating operation for this family down to -15 °C, Inverter technology, and the use of R-32 refrigerant.
Why install a heat pump on a wall bracket in Chambly?
For this project, the ground immediately in front of the house consists of soil and vegetation. Placing the compressor directly at ground level would have created several disadvantages.
In particular, we wanted to avoid:
- a buildup of leaves around the heat exchanger;
- direct contact with snow;
- potential ground movement;
- a slab unnecessarily occupying planting space;
- difficult drainage of defrost water;
- reduced access beneath the unit.
The wall bracket keeps the unit several dozen centimetres above the ground while completely freeing up the space beneath the compressor.
This also results in a visually cleaner installation.
In the photo, the two horizontal arms support the unit through clearly distinct mounting points, while the vertical posts are anchored into the building’s structure.
Vibration isolators visible beneath the compressor
Another interesting detail of this installation in Chambly can be found between the heat pump’s feet and the metal bracket.
We can see vibration isolators installed at the support points.
These are small components, but they play an important role.
The compressor and fan naturally produce slight vibrations while operating. Without proper decoupling, some of these vibrations could be transmitted to the bracket and then to the structure of the house.
A wall-mounted installation must therefore be approached differently from an installation on a slab.
When we use a bracket attached to the building, we pay particular attention to:
- the rigidity of the bracket;
- the unit’s level;
- the anchor points;
- the vibration isolators;
- the clearance from the wall.
These are precisely the details that make it possible to achieve a durable and discreet HVAC installation.
A heat pump installed high enough to withstand the snow
Outdoor height is particularly important in Chambly and throughout Greater Montreal.
A heat pump needs to breathe.
If snow reaches the bottom of the heat exchanger, airflow may be restricted. If ice accumulates beneath the machine during defrost cycles, it may gradually reach the base of the unit.
In this installation, the clearance beneath the compressor provides a valuable margin.
Water produced during a defrost cycle can fall beneath the machine rather than accumulate directly in an enclosed base.
This area must of course always be kept clear during the winter. An elevated installation does not mean that a snowdrift should be allowed to cover the front or sides of the unit.
The brick wall required precise planning of the location
The photo shows a façade made up of two distinct sections: a concrete foundation at the bottom and brick siding above.
We positioned the bracket to create a stable installation while respecting the wall’s configuration.
We also had to work around:
- a window located above and to the left;
- the pipes entering the house on the right;
- an outdoor electrical box;
- vegetation at ground level;
- the space required in front of the fan.
This last element is essential.
The large fan visible on the front of the outdoor unit needs sufficient space to discharge air properly. Installing a heat pump in a corridor that is too narrow or immediately in front of a fence can reduce its efficiency and complicate its operation.
Fujitsu AIRSTAGE Altair 500: a series covering multiple capacity levels
The Altair 500 series is available in different capacities to meet the needs of buildings of different sizes and configurations.
The Fujitsu data sheet lists the following nominal cooling capacities:
- 9,000 BTU/h for the 09KPAS1;
- 12,000 BTU/h for the 12KPAS1;
- 18,000 BTU/h for the 18KPAS1;
- 22,000 BTU/h for the 24KPAS1;
- 30,000 BTU/h for the 30KPAS1;
- 33,000 BTU/h for the 36KPAS1.
For heating, the advertised nominal capacities are respectively 10,000, 14,000, 18,000, 24,000, 30,000, and 34,000 BTU/h.
However, we emphasize one important point: the capacity to install must be determined based on the building, not simply on an approximate square-footage figure.
What we consider before choosing the BTUs
For a home in Chambly, we can consider many factors before selecting a wall-mounted heat pump:
- wall and roof insulation;
- number and dimensions of windows;
- solar orientation;
- actual volume to be conditioned;
- open-plan layout or partitioned rooms;
- floor where the indoor unit will be located;
- existing heating system;
- wind exposure;
- the room’s daily use.
An oversized heat pump is not automatically better.
The Inverter compressor offers a wide modulation range, but proper sizing remains preferable for achieving good operating cycles and effective summer dehumidification.
Efficiency varies by model
The Altair 500 product-range data sheet shows TRÈS2 values from 21.0 to 26.0, depending on capacity.
The 09KPAS1 is listed at 26.0, the 12KPAS1 at 24.0, the 18KPAS1 at 22.0, the 24KPAS1 at 21.5, the 30KPAS1 at 22.0, and the 36KPAS1 at 21.0.
This shows why we do not compare only two heat pumps by looking at their brand name or nominal capacity.
Performance can vary significantly from one capacity to another within the same product range.
Inverter technology for maintaining a more stable temperature
The compressor in the Fujitsu AIRSTAGE Altair 500 uses Inverter technology.
Its main advantage is modulation.
Once the setpoint temperature is reached, the unit can reduce its output instead of continually switching between full power and shutting off.
This generally provides:
- a more consistent indoor temperature;
- less abrupt start-ups;
- greater comfort;
- quieter operation;
- energy consumption adapted to demand.
Fujitsu also indicates that H-series AIRSTAGE systems can provide energy savings of up to 30%, depending on the installation and operating conditions.
R-32, piping, and the technical details that really matter during installation
An R-32 refrigerant heat pump
The label R32 is clearly visible on the outdoor unit photographed in Chambly.
This is an important characteristic of this Fujitsu generation.
According to the manufacturer’s documentation, R-32 has a global warming potential of 675, compared with 2,088 for R-410A. Fujitsu presents this as a 68% reduction in GWP.
The choice of refrigerant also influences installation practices.
An R-32 heat pump must be handled using procedures and equipment suited to this refrigerant.
This is an additional reason to entrust the work to a qualified HVAC team rather than treating the machine like an ordinary electrical appliance that merely needs to be connected.
Different pipe sizes depending on capacity
The piping is one of the most important aspects of a heat pump installation.
For the Altair 500, Fujitsu specifies:
- 9,000 and 12,000 BTU models: 1/4 in. liquid + 3/8 in. gas;
- 18,000 and 24,000 BTU models: 1/4 in. liquid + 1/2 in. gas;
- 30,000 and 36,000 BTU models: 3/8 in. liquid + 5/8 in. gas.
These differences are particularly important when replacing an old unit.
We regularly meet homeowners who want to keep the existing pipes in order to reduce the amount of work.
It is sometimes possible, but never automatic.
We must confirm:
- the copper diameter;
- the condition of the insulation;
- the length;
- the type of old refrigerant;
- the interior condition of the pipes;
- the new manufacturer’s requirements.
Maximum lengths allowing for flexible installation
Fujitsu also specifies different maximum piping lengths.
The documentation states:
- 66 ft for the 9,000 and 12,000 BTU models;
- 98 ft for the 18,000 and 24,000 BTU models;
- 164 ft for the 30,000 and 36,000 BTU models.
The maximum vertical difference can reach 49, 82, or 98 feet depending on the capacity group.
This flexibility can be useful in complex projects in Montréal, particularly in duplexes and triplexes, but also in Laval, Longueuil, the North Shore and the South Shore, when the indoor unit is far from the ideal location for installing the compressor.
In this Chambly project, the outdoor route is instead very compact, allowing for a relatively direct path.
The pipes visible in the photo have been neatly grouped together
On the right side of the outdoor unit, we can clearly see the lines leading to the building.
We sought to maintain a natural curve rather than an excessively tight angle.
This is important because a copper line must not be crushed or bent in a way that reduces its internal diameter.
The visible insulation also protects the gas line, which plays an essential role in the refrigeration cycle.
Grouping the lines improves all of the following simultaneously:
- mechanical protection;
- the exterior appearance;
- accessibility;
- the durability of the installation.
Heating operation down to -15 °C
Fujitsu specifies a heating operating range of -15 °C to 24 °C for all Altair 500 models listed in this technical sheet.
This feature must be understood correctly.
In Quebec, temperatures below -15 °C are quite common.
Altair 500 must therefore be selected with the home's overall heating strategy in mind.
Some homeowners mainly want to reduce their use of electric baseboard heaters during milder periods.
Others are looking for a heat pump capable of operating during nearly all extreme cold spells.
These two needs do not necessarily lead to the same system choice.
At AirGreen, we prefer to explain this limitation clearly before installation.
Several Energy Star models
The Fujitsu sheet classifies several Altair 500 units in different Energy Star categories, including ES, ESCC, and ESME, depending on capacity.
Actual eligibility for financial assistance or a subsidy should never be determined solely from the commercial name “Altair 500.”
Programs may require:
- a specific combination of indoor and outdoor units;
- an AHRI number;
- a specific capacity;
- a specific certification;
- compliance with the conditions in effect at the time of purchase.
Before promising a subsidy amount, we therefore verify the exact model and the criteria applicable to the project.
Up to 19 dB(A) indoors, depending on capacity
A wall-mounted heat pump is installed in a living space. Its indoor sound level is therefore often more important than a few performance points on a technical sheet.
Fujitsu indicates a sound level as low as 19 dB(A) in quiet mode for the 9,000 and 12,000 BTU models.
The quiet-mode values are then 26 dB(A) for the 18,000 BTU model, 31 dB(A) for the 24,000 BTU model, and 32 dB(A) for the 30,000 and 36,000 BTU models.
For a bedroom or office, this difference is worth considering when sizing the system.
Outdoor sound levels matter too
The technical sheet also provides the sound levels of the outdoor units, with values that vary according to capacity.
In a residential neighborhood like Chambly, we always consider the immediate surroundings:
- homeowner's window;
- neighbor's window;
- patio;
- side passage;
- bedroom;
- property line.
The wall bracket shown here also keeps the unit close to the façade and avoids unnecessarily extending it into the yard.
Electrical installation according to the model
The series operates at 208 to 230 V, 60 Hz, single-phase.
The electrical protection specified by Fujitsu is:
- 15 A for the 09KPAS1, 12KPAS1, and 18KPAS1 models;
- 20 A for the 24KPAS1;
- 30 A for the 30KPAS1 and 36KPAS1 models.
During our installations, we never size the electrical supply based on a simple estimate.
We confirm the exact requirements for the installed model and the capacity available in the electrical panel.
A practical detail: keep vegetation away from the outdoor unit
The photo from Chambly shows plants to the left of the compressor.
At the time of installation, they remain far enough away not to block the unit.
But vegetation grows.
We therefore recommend that the homeowner check this area during the summer.
A plant that gradually reaches the coil can:
- limit airflow;
- trap moisture and debris;
- complicate cleaning;
- reduce performance.
There is no need to eliminate all landscaping around a heat pump. You simply need to maintain the required clearances.
An outdoor unit must remain accessible for HVAC maintenance
This installation offers another advantage: the service panel and connections remain accessible.
On many projects, we see units installed behind a fixed fence, beneath a very low patio, or in a space where opening the panel becomes nearly impossible.
This makes HVAC maintenance work take longer and can complicate certain repairs.
In Chambly, we kept a layout that allows technicians to approach the unit and work around it without having to dismantle outdoor landscaping.
What we want to avoid with a wall-mounted installation
For this type of project, several mistakes can reduce the final quality:
- install the compressor too low;
- choose an undersized support;
- omit vibration-damping components;
- create unnecessary loops in the copper lines;
- place the unit in the path of vegetation;
- block access to the service panel;
- neglect winter defrosting;
- install the unit without checking the manufacturer's required clearances.
A quality heat pump installed without considering these details can become noisy, difficult to maintain, or less efficient.
Why this photo of an installation in Chambly sums up our approach so well
This installation may seem simple at first glance: a Fujitsu heat pump mounted on a house wall.
But several technical decisions become apparent when looking more closely at the installation.
The compressor is raised.
It is installed on a wall-mounted metal bracket.
Anti-vibration isolators are present.
The front of the fan is unobstructed.
The lines follow a compact route.
The ground remains clear beneath the unit.
The vegetation is not crushed by a slab.
The service panel remains accessible.
This is precisely the kind of result we strive for at AirGreen.
Our approach in Chambly, Montreal, Laval, Longueuil, on the North Shore, and on the South Shore
Buildings vary from one city to another, but the principles remain the same.
In Montreal, we often work with alleys, balconies, and façades where space is limited.
In Laval and on the North Shore, detached homes often offer more options, but we still have to choose the right location from among several possibilities.
In Longueuil, Chambly, and on the South Shore, we encounter as many brick homes like this one as newer constructions with completely different configurations.
In every case, we assess the installation as a complete system.
We want the wall-mounted heat pump to be efficient from the day it is started up, but also to remain easy to maintain and consistent with the building several years later.
A properly installed Fujitsu Altair 500 is more than just a machine mounted on the wall
The Fujitsu AIRSTAGE Altair 500 combines several appealing features: R-32 refrigerant, Inverter technology, capacities ranging from 9,000 to 36,000 BTU across the range, several Energy Star ratings depending on the model, quiet operation, and various control accessories.
Fujitsu documentation also mentions ProCore copper coils with increased corrosion resistance, Hydro Fin coils, and various control options, including certain Wi-Fi adapters, 24 V interfaces, BACnet, and Modbus.
But in a real installation in Chambly, the specifications on paper are only one part of the project.
The next step is to turn this machine into a system that is properly integrated into the home.
That is exactly what this installation demonstrates: an outdoor unit positioned methodically, protected from common ground- and winter-related problems, securely mounted, and neatly connected.
At AirGreen, it is this combination of equipment selection, HVAC installation, and finishing quality that enables us to complete heat pump projects in Chambly, Montreal, Laval, Longueuil, on the North Shore, and on the South Shore with a consistent, long-lasting approach.