In Godmanchester, a Fujitsu Altair 700 installed with precision in a room with very real architectural constraints
This installation carried out by our AirGreen team in Godmanchester perfectly illustrates an aspect that is often underestimated when choosing a wall-mounted heat pump: the quality of the result depends just as much on the equipment as on where it is installed.
In the project photo, the indoor unit Fujitsu AIRSTAGE Altair 700 is installed very high on a wall, immediately beneath a section of sloped ceiling. The room’s geometry is therefore not that of a classic rectangular room with a perfectly horizontal ceiling. We had to find a location that would maintain good air distribution while respecting the existing architectural configuration and integrating the unit neatly into the décor.
The result is deliberately understated: a white wall-mounted unit installed in the upper section of the wall, with the technical routing concentrated on the left side of the unit. In a room with light-colored walls like this one, the Fujitsu Altair 700 blends in naturally without becoming the dominant visual element.
This project in Godmanchester, in Montérégie, shows why an HVAC installation should never be treated as a simple operation consisting of “hanging a heat pump on the wall.” Positioning, airflow, condensate drainage, refrigerant connections, electrical supply, and future accessibility must all be considered before the first hole is drilled.
A wall-mounted heat pump placed very high to make better use of the available space
The most interesting feature of this installation is immediately visible: the indoor unit is located near the ceiling.
This positioning is generally advantageous for a wall-mounted heat pump, since the treated air can be directed into the room rather than straight at the occupants. But when the ceiling is sloped, as it is here, it becomes particularly important to find a position that does not hinder the opening of the louvers or the circulation of air around the unit.
We must also leave enough space to allow access to the filters and various components during future HVAC maintenance.
A unit installed a few centimetres too high or too close to a corner may seem acceptable during the work, but can become problematic when the front panel needs to be opened, a filter removed, or the unit serviced.
In this Godmanchester project, the unit is positioned beneath the horizontal section of the ceiling, before it slopes downward to the right. This makes use of a usable section of wall while keeping the front and air outlet completely unobstructed.
An interior configuration that required more than a simple aesthetic choice
The photo also reveals a room with several changes in angle at the ceiling and along the right-hand wall.
This type of geometry influences how we think about air circulation.
A wall-mounted heat pump heats and cools primarily by moving the room air. It is therefore important to avoid, as much as possible, locations where airflow would immediately be blocked by a beam, a wall return, a cabinet, or a sloped ceiling.
In an installation like this, our goal is to create a sufficiently clear air path so the unit can make use of its capacity without having to operate unnecessarily at high speed.
The Fujitsu Altair 700 also features automatic vertical air direction and four fan speeds plus an automatic mode. According to the Fujitsu technical specifications, airflow can reach 680 m³/h, or approximately 400 cfm, at high speed for the 09KMAS1 and 12KMAS1 models.
Fujitsu AIRSTAGE Altair 700: two available capacities
The Altair 700 series technical documentation covers two configurations:
- 09KMAS1, with a rated cooling capacity of 9,000 BTU/h;
- 12KMAS1, with a rated cooling capacity of 12,000 BTU/h.
The 9,000 BTU model offers a cooling range of 3,100 to 12,100 BTU/h and a rated heating capacity of 12,000 BTU/h.
The 12,000 BTU model has a cooling range of 3,100 to 13,800 BTU/h, with a rated heating capacity of 14,000 BTU/h.
The interior photograph does not show the nameplate, so it is not possible to confirm which of these two capacities was installed in Godmanchester. We prefer to preserve this distinction rather than arbitrarily assign a BTU rating to the installation.
For our customers, this is also a useful reminder: the capacity of a heat pump should never be determined solely by its exterior appearance. Two visually nearly identical indoor units may offer different capacities and performance levels.
Particularly impressive energy efficiency
The Fujitsu AIRSTAGE Altair 700 series delivers high efficiency ratings.
For the 9,000 BTU model, Fujitsu indicates a 30.0 TRÈS2. For the 12,000 BTU model, the stated value is 27.5.
Both models also appear with the ENERGY STAR classifications indicated in the manufacturer’s documentation.
For a homeowner comparing several wall-mounted heat pumps in Montréal, Laval, Longueuil, on the North Shore or the South Shore, these figures are important, but they are only part of the equation.
High performance on paper does not eliminate the need to:
- to size the system correctly;
- to comply with piping lengths and diameters;
- to perform an adequate vacuum;
- to position the indoor unit correctly;
- to ensure proper drainage;
- to properly protect the outdoor installation.
The final efficiency of an HVAC installation always depends on all these elements.
R-32: the new generation of refrigerant used by the Altair 700
The Fujitsu Altair 700 uses R-32 refrigerant.
Fujitsu states in its documentation that R-32 has a global warming potential of 675, compared with 2,088 for R-410A, corresponding to an announced 68% reduction in GWP. The manufacturer also emphasizes that its R-32 systems require less refrigerant while maintaining their heating performance.
This development is particularly relevant for homeowners replacing an older heat pump.
The refrigerant type influences the technical procedures used during installation and servicing. The work should therefore be entrusted to an HVAC company equipped and trained to service current generations of systems.
Inverter technology to avoid on-off operation
The Altair 700 uses an Inverter compressor.
This technology allows the system to adjust its output according to the room’s actual heating or cooling demand.
When a room is very hot in summer, the heat pump can operate at a higher output to quickly reach the requested temperature. Once that temperature is nearly reached, the system gradually reduces its capacity instead of simply shutting down completely.
This modulation provides several practical benefits:
- more stable indoor temperature;
- reduced on-off cycling;
- quieter operation at low load;
- better adaptation to changes in outdoor temperature;
- consumption more consistent with the room’s actual needs.
For this Godmanchester installation, this variable-capacity operation is particularly relevant because the unit is installed in a room with an uneven ceiling geometry. Adjustable output allows the system to maintain comfort without necessarily operating continuously at maximum capacity.
Up to 19 dB(A) indoors
In a residential room, the noise from a heat pump can become just as important as its performance.
Fujitsu indicates an indoor sound level that can drop to 19 dB(A) in quiet mode, with a value of 21 dB(A) in heating in the same mode.
At high speed, the indoor unit reaches 40 dB(A) in cooling and 42 dB(A) in heating.
These values help explain why this range may be suitable for spaces where a quiet environment is desired, including a bedroom, living room, home office, or living area.
The outdoor sound level is also relatively contained. Fujitsu indicates:
09KMAS1 : 44 dB(A) in cooling and 47 dB(A) in heating.
12KMAS1 : 48 dB(A) in cooling and 50 dB(A) in heating.
An indoor unit only 32 13/16 inches wide
The dimensions are another advantage in an installation like this.
The Altair 700 indoor unit measures approximately:
32 13/16 in wide
10 5/8 in high
8 3/4 in deep
It weighs approximately 22 lb.
These dimensions are identical for the 9,000 and 12,000 BTU versions listed in the Fujitsu specifications.
In the Godmanchester photo, the benefit of this relatively compact format is immediately clear. The space between the ceiling and the sloped section of the wall imposes constraints. A much larger unit could have been difficult to integrate without compromising either the aesthetics or the clearances required for operation.
The visible technical routing on the left side: a normal detail in a real installation
To the left of the indoor unit, we can see a small technical section containing the connection routing.
In some properties, it is possible to conceal the piping entirely inside a wall. In others, the building’s configuration requires a surface-mounted route or a side exit.
Our priority is therefore to make this routing as short, clean, and logical as possible.
A truly professional installation does not mean that all lines must be completely hidden. It means their routing must meet the system’s requirements, allow for proper drainage, and avoid unnecessary modifications to the building’s structure.
1/4 in liquid line and 3/8 in gas line
For both capacities in the Altair 700 series, Fujitsu requires the same refrigerant line sizes:
liquid line: 1/4 in
gas line: 3/8 in
The minimum piping length is 3 m, or approximately 10 ft.
The maximum permitted length is 20 m or 66 ft, with a maximum height difference of 14.9 m or 49 ft. The documentation also specifies a pre-charge corresponding to 14.9 m or 49 ft of piping.
These figures may seem secondary to a homeowner, but they are essential when planning the project.
They determine, among other things, how far we can place the outdoor unit from the indoor unit without exceeding the manufacturer’s specified parameters.
A 208–230 V power supply with 15 A protection
The 09KMAS1 and 12KMAS1 models operate on a 208 to 230 V, 60 Hz, single-phase power supply.
The technical specifications indicate a 15 A circuit breaker for both capacities.
This may facilitate certain residential projects where electrical capacity is limited, but we must always inspect the electrical panel before concluding that an installation can be completed without modifications.
For the 9,000 BTU model, Fujitsu specifies a maximum current of 6.4 A in cooling mode and 9.4 A in heating mode.
For the 12,000 BTU model, the listed maximum values are 6.9 A in cooling mode and 9.4 A in heating mode.
Modulating consumption rather than a single figure
It is also useful to examine the rated power consumption.
For the 09KMAS1, Fujitsu specifies a rated power consumption of:
- 0.55 kW in cooling mode;
- 0.76 kW in heating mode.
For the 12KMAS1:
- 0.89 kW in cooling mode;
- 0.95 kW in heating mode.
These values do not mean that the heat pump constantly consumes this amount of electricity. Since it is an Inverter system, consumption varies according to the required load.
That is precisely why comparing only the instantaneous electrical power of two units does not provide a complete picture of seasonal efficiency.
Heating down to -15 °C: Understanding the Altair 700’s intended purpose
Fujitsu’s stated heating operating range extends down to -15 °C.
It is essential not to present this value as though it automatically meant that the heat pump should be the sole source of heating during every cold spell in Quebec.
In Godmanchester, winter temperatures can drop below this threshold.
Depending on the building and the existing heating system, we must therefore consider the Fujitsu Altair 700 as part of an overall energy strategy.
It can meet a large portion of the heating needs when conditions fall within its operating range, while another heat source can take over when conditions require it.
For a homeowner who wants to maximize heat pump use at much lower temperatures, it may be worthwhile to compare other Fujitsu series specifically designed for extreme cold.
A heating capacity higher than the nominal cooling capacity
The technical specifications do, however, show an interesting feature.
The 9,000 BTU air-conditioning model provides up to 14,500 BTU/h of heating within its modulation range.
The 12,000 BTU model can reach 15,000 BTU/h in heating.
Fujitsu also states in its documentation that the outdoor unit in the Altair 700 series can provide up to 33% more heat than the labeled nominal capacity, depending on operating conditions.
This clearly illustrates why the number of BTUs in a system’s commercial name does not tell the whole story.
Built-in Wi-Fi and the AIRSTAGE app
The Altair 700 series also includes built-in Wi-Fi connectivity.
The system can be monitored and controlled remotely through the compatible AIRSTAGE mobile app.
This feature is particularly convenient in a home where the heat pump is used daily. The owner can adjust a setting or check the system’s operation without having to be directly in front of the unit.
Fujitsu also provides several advanced control options, including wired controllers and BACnet- or Modbus-compatible interfaces for certain more complex applications.
ProCore copper coils: an internal feature not visible in the photo
According to Fujitsu, the Altair 700 indoor unit uses highly corrosion-resistant ProCore copper coils.
It is a technical detail that is invisible after installation but important for the equipment’s durability.
The manufacturer’s brochure also mentions:
- automatic defrost;
- automatic restart;
- an economy mode;
- a minimum heat mode;
- a wireless remote control;
- a low-noise outdoor mode.
All these features position the Altair 700 as a compact wall-mounted solution designed to provide heating and cooling with a relatively simple interface for the user.
Drainage: an invisible but essential detail
In a completed photo like the one from Godmanchester, the customer mainly sees a clean and discreet unit.
What is not necessarily visible is the work behind the drainage system.
In air conditioning, a heat pump removes moisture from indoor air. This water must be drained properly.
The Fujitsu specifications indicate a moisture removal capacity of 1.38 L/h for the 9,000 BTU model and 1.73 L/h for the 12,000 BTU model.
An improper drain slope or poorly designed routing can eventually cause:
- water leaks indoors;
- a buildup in the condensation pan;
- odors;
- wall damage;
- avoidable service calls.
We therefore pay just as much attention to the drain as to the refrigerant connections.
What this Godmanchester installation can teach a homeowner before their own project
Do not choose the location solely because a wall is empty
The first lesson from this installation is simple: an empty space on a wall is not automatically a good location for a wall-mounted heat pump.
We look in particular at the direction in which the air will be blown.
In an open-concept area, the goal may be to direct air toward as much of the home as possible. In a bedroom, we generally try to avoid blowing air directly onto the bed. In a room with a sloped ceiling, as in Godmanchester, the ceiling angles can also affect air circulation.
Do not oversize “just to be sure”
Another common instinct is to request a larger unit than necessary.
An inverter heat pump can modulate its capacity, but this does not justify significant oversizing.
The right capacity generally makes it possible to:
- to maintain a more uniform temperature;
- to improve summer dehumidification;
- to limit certain unnecessary cycles;
- to maintain a better balance between comfort and energy consumption.
We therefore determine capacity based on the building rather than on the assumption that “more BTUs always means more comfort.”
Check heating needs at very low temperatures
A homeowner looking for a Fujitsu heat pump in Godmanchester must also compare the operating range of each product line with their goals.
The Altair 700 is advertised as operating in heating mode down to -15 °C. If the goal is instead to operate the heat pump as the primary heat source during significantly lower temperatures, we must examine series offering cold-climate performance suited to this requirement.
This discussion before installation is much more important than simply choosing the logo on the unit.
Always verify actual eligibility for grants
The technical sheet identifies the Altair 700 models presented with different ENERGY STAR certifications.
This may be relevant for certain financial assistance programs, but eligibility for a grant must always be confirmed based on the exact unit pairing, the applicable AHRI number, and the program rules in effect at the time of installation.
At AirGreen, we avoid promising an amount simply because a model carries an energy certification.
Programs evolve. A precise review is therefore necessary before presenting an amount as guaranteed.
A clean installation must also remain easy to maintain
The photo from Godmanchester shows a relatively minimalist installation: a white unit mounted high on a light-colored wall, with very few visible components.
But an aesthetically pleasing installation must also remain accessible.
The indoor unit’s filters must be cleaned regularly. It must remain possible to open the front panel and, if necessary, carry out a deep cleaning of the wall-mounted heat pump.
We therefore consider future servicing when choosing the location.
A unit can operate for years. Spending a few extra minutes on its positioning during installation can make maintenance much simpler throughout its service life.
The AirGreen approach: adapt the heat pump to the building, not the building to the heat pump
This project in Godmanchester aptly summarizes our approach to HVAC installation.
We start with the property as it exists.
In this case, we had a bright room with an unusual ceiling configuration and available space near the upper part of the wall. The Fujitsu AIRSTAGE Altair 700 fit into this space thanks to its compact design while maintaining unobstructed airflow.
The same logic applies to our other heat pump installations in Montreal, Laval, Longueuil, on the North Shore, and on the South Shore.
Every building presents its own constraints: stone walls, finished basements, cathedral ceilings, open staircases, condos with condominium association rules, older homes, or renovations where mechanical pathways are already very crowded.
Our role is to find the solution that truly works under these conditions.
A discreet yet technically complete Fujitsu Altair 700
Ultimately, this Fujitsu AIRSTAGE Altair 700 wall-mounted heat pump installation in Godmanchester combines several noteworthy features: Inverter technology, R-32 refrigerant, high energy efficiency, built-in Wi-Fi, indoor operation as quiet as 19 dB(A), 208–230 V power on a 15 A circuit, and 1/4 in. and 3/8 in. refrigerant connections.
But above all, this project shows that technical specifications only reach their full potential once the equipment has been properly integrated into the building.
The location beneath the sloped ceiling, the clearance in front of the unit, its elevated position on the wall, and the concentrated routing of the connections show an installation adapted to the space rather than a standardized installation.
At AirGreen, it is this combination of equipment selection, precise HVAC installation, and understanding of the building that enables us to complete durable, functional, and easy-to-maintain projects throughout the Greater Montreal area and Montérégie.