Installation of a 12,000 BTU Fujitsu AIRSTAGE Altair 700 wall-mounted heat pump in Salaberry-de-Valleyfield, Montérégie

In Salaberry-de-Valleyfield, a 12,000 BTU Altair 700 installed on a rooftop with an elevated structure designed for Quebec winters

For this project completed in Salaberry-de-Valleyfield, our AirGreen team installed a Fujitsu AIRSTAGE Altair 700 wall-mounted heat pump in a configuration that deserves particular attention: the outdoor unit is located on a flat roof, elevated using a sturdy metal structure rather than simply placed on the membrane.

The photograph taken after the installation provides a particularly useful technical clue this time. The EnergyGuide label visible directly on the outdoor unit indicates a cooling efficiency of 27.5. In the Fujitsu documentation provided for the Altair 700 series, the 12,000 BTU/h 12KMAS1 model has a SEER2 rating of precisely 27.5, while the 9,000 BTU model is rated at 30.0 SEER2. This match allows us to identify this installation much more precisely as the 12,000 BTU Fujitsu Altair 700 configuration.

Beyond the machine’s efficiency, the photo primarily tells the story of the installation. We had to integrate a modern heat pump using R-32 refrigerant on a roof already occupied by mechanical equipment, while maintaining sufficient clearance for operation, defrosting, maintenance, and the winter conditions specific to the Salaberry-de-Valleyfield region.

A rooftop installation that leaves nothing to chance

The outdoor unit is mounted on a metal frame that creates considerable clearance between the unit and the roof.

Under the beams, wooden pieces can be seen serving as distribution and support elements. Everything is installed on a protected section of the roof, where a SOPREMA-type insulation panel can also be seen.

This configuration meets several needs simultaneously.

First, we must protect the roof. An outdoor heat pump should not unnecessarily concentrate all its weight on a few small contact points. A properly designed structure helps distribute the load more evenly.

Second, we must protect the heat pump itself. A unit installed too close to the roof can become vulnerable to accumulations of snow, ice, and water.

Third, we must think about the technician who will one day return to service or diagnose the equipment. The panels, connections, and components must remain accessible.

This logic applies in Salaberry-de-Valleyfield as well as in our installations in Montréal, Laval, Longueuil, on the North Shore, and on the South Shore.

Why this height matters when the heat pump is heating

In summer, the structure’s purpose seems simple: to hold the unit securely in place.

In winter, its role becomes even more important.

When a heat pump operates in heating mode, the outdoor coil can accumulate frost. The system must then periodically perform an automatic defrost cycle to melt this ice.

All this water has to go somewhere.

If the outdoor unit is almost level with the roof, water can freeze immediately beneath it and, over successive cycles, create an accumulation that gradually rises toward the base of the heat pump.

By raising the unit sufficiently, we gain several advantages:

• more space for water drainage;
• more clearance before the snow reaches the bottom of the unit;
• less contact between the chassis and accumulated ice;
• better visual access beneath the machine;
• more practical clearance for future HVAC maintenance.

In Salaberry-de-Valleyfield, where alternating cold, snow, thawing, and refreezing are normal winter conditions, this installation detail deserves as much attention as the choice of brand.

An electrical box installed directly near the unit

The photograph also shows a metal electrical box mounted on the right side of the support.

This arrangement provides a disconnect or connection point near the outdoor unit while keeping the installation organized.

The goal is to avoid an improvised assembly of cables and exposed components around the unit. On a roof, where equipment is exposed to sun, rain, wind, snow, and significant temperature fluctuations, the quality of the outdoor electrical installation is especially important.

Fujitsu documentation indicates that the Altair 700 operates on a 208 to 230 V, 60 Hz, single-phase power supply, with a 15 A circuit breaker for the 09KMAS1 and 12KMAS1 models.

For the 12,000 BTU model corresponding to this installation, the indicated maximum current is 6.9 A in cooling mode and 9.4 A in heating mode.

The EnergyGuide label visible in the photo confirms an important point

This installation is interesting because the yellow EnergyGuide label is still perfectly visible on the front of the unit.

It shows a cooling efficiency of 27,5.

The Fujitsu Altair 700 series data sheet confirms that the 12,000 BTU 12KMAS1 model has a SEER2 rating of 27.5. The 9,000 BTU model, meanwhile, has a SEER2 rating of 30.0.

This therefore gives us a concrete element linking the photographed unit to the 12,000 BTU model.

For our installation articles, we always prefer to work this way: start with a detail that is clearly visible at the job site and compare it with the manufacturer’s technical data rather than assigning a capacity simply based on the apparent size of the unit.

Fujitsu AIRSTAGE Altair 700 12,000 BTU: the technical specifications that really matter

This Fujitsu wall-mounted heat pump configuration, 12KMAS1, offers a rated cooling capacity of 12,000 BTU/h.

But rated capacity tells only part of the story.

Thanks to the inverter compressor, the system can modulate its output between 3,100 and 13,800 BTU/h in cooling mode.

In heating mode, Fujitsu indicates a rated capacity of 14,000 BTU/h, with an operating range from 2,800 to 15,000 BTU/h.

This modulation capability allows the heat pump to reduce its output when demand is low instead of constantly operating at full capacity.

27.5 SEER2: high efficiency for a 12,000 BTU heat pump

The SEER2 rating of 27.5 is one of the model’s most notable features.

SEER2 allows the seasonal cooling efficiency of different units to be compared. The higher this value, the less energy the heat pump needs to consume to provide a given amount of cooling under standardized test conditions.

The Fujitsu technical data sheet also lists the following for the 12KMAS1 model:

• HSPF2 Region V: 8.5;
• EER2: 13.5;
• COP2: 4.32.

For a homeowner comparing several wall-mounted heat pumps in Salaberry-de-Valleyfield, SEER2 should never be the only criterion.

You should also consider:

• actual heating capacity;
• minimum operating temperature;
• noise level;
• electricity consumption;
• installation quality;
• service availability;
• eligibility for financial assistance programs.

Heating down to -15 °C

Fujitsu indicates a heating operating range of -15 °C to 24 °C for this series.

In cooling mode, the unit can operate between -10 °C and 50 °C.

However, the fact that a unit can operate at -15 °C does not automatically mean it can cover all of a building’s heating needs on its own throughout every winter day.

In Salaberry-de-Valleyfield, we also consider:

• the dimensions of the heated area;
• insulation;
• air infiltration;
• the number of windows;
• wind exposure;
• the desired indoor temperature;
• the existing supplementary heating system.

Serious heat pump sizing means assessing the building’s needs, rather than simply using an approximate square-foot-per-BTU rule.

R-32: clearly identified on the outdoor unit

The logo R32 is visible on the unit’s front panel.

This generation of Altair 700 therefore uses R-32 refrigerant rather than traditional R-410A.

In the documentation provided, Fujitsu compares a global warming potential of 675 for R-32 with 2,088 for R-410A, representing a stated reduction of approximately 68% in GWP.

For the customer, the refrigerant change does not affect the heat pump’s day-to-day use. For our installation team, however, it requires following the procedures and using the equipment suited to this new generation of systems.

1/4 in. and 3/8 in. refrigerant lines

The 12,000 BTU Fujitsu Altair 700 uses:

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

This information is particularly important when replacing an older heat pump.

You should never assume that existing piping in a building is automatically compatible simply because it “looks like” the new piping.

We check in particular:

• their diameter;
• their length;
• their condition;
• their routing;
• their insulation;
• their compatibility with the planned installation.

For this series, Fujitsu allows a line-set length of up to 66 feet, with a specified precharge of up to 49 feet and a maximum vertical difference also of 49 feet.

This flexibility is particularly useful in a rooftop project like the one in Salaberry-de-Valleyfield.

A very practical compact format for flat roofs

The outdoor unit associated with the 12KMAS1 model measures:

• 31 7/16 in. wide;
• 21 5/16 in. high;
• 11 7/16 in. deep;
• net weight of approximately 71 lb.

This reduced depth is particularly advantageous on a roof where vents, ventilation outlets, parapets, ducts, and existing equipment must be accommodated.

The site photograph also shows a large ventilation component to the right of the installation.

Our job is therefore to position the outdoor unit without compromising either its own airflow or access to the other rooftop equipment.

An indoor unit that can reach 19 dB(A)

Indoors, the Fujitsu Altair 700 can operate at just 19 dB(A) in quiet cooling mode.

In heating mode, the corresponding value is 21 dB(A).

For the 12,000 BTU model, Fujitsu indicates the following outdoor levels:

• 48 dB(A) in cooling mode;
• 50 dB(A) in heating mode.

Noise is often overlooked when a customer compares heat pumps.

However, a difference of just a few decibels can become very noticeable when an indoor unit is located near a bedroom, office, or living room.

Built-in Wi-Fi to control the heat pump remotely

The Altair 700 also offers built-in Wi-Fi connectivity.

Fujitsu provides remote management through the AIRSTAGE app.

This feature can allow the homeowner to:

• change the temperature remotely;
• prepare the home before returning;
• lower the setpoint while away;
• monitor system operation more easily;
• avoid certain adjustment oversights.

The documentation also mentions several advanced integration options with optional interfaces and controllers, including BACnet and Modbus-compatible solutions.

ProCore coils and washable filter

Fujitsu states that the indoor unit uses highly corrosion-resistant copper ProCore coils.

The filter is also washable.

The features available in this generation include, in particular:

• energy-saving mode;
• minimum heat mode;
• automatic defrost;
• automatic restart;
• wireless control;
• automatic vertical louver adjustment.

For a homeowner, these features do not replace proper sizing, but they contribute to everyday comfort.

An ENERGY STAR installation that must be verified according to the selected rebate program

The technical data sheet classifies the models in this series in the ENERGY STAR categories indicated by Fujitsu.

For homeowners looking for a heat pump rebate in Salaberry-de-Valleyfield, we nevertheless always verify eligibility based on the exact combination of units and the program available at the time of installation.

It is not enough to see an ENERGY STAR logo in a brochure.

Depending on the program, eligibility may depend on:

• the exact indoor unit number;
• the exact outdoor unit number;
• the certification number;
• low-temperature capacity;
• the type of dwelling;
• the installation date;
• the administrative rules in effect.

This is a step homeowners should take before choosing a machine solely to obtain an advertised financial incentive.

What we paid particular attention to in this Salaberry-de-Valleyfield installation

Each job-site photo reveals certain choices that a technical data sheet never shows.

Here, several elements are particularly important.

Unit height

The unit is high enough to leave a large amount of clearance beneath the outdoor unit.

For defrosting and snow, this is an obvious advantage.

The four fastening points

The heat pump feet are installed on the support’s metal crossbar rather than on an uneven surface.

This helps stabilize the unit.

Roof protection

The support posts do not rest on the roof without careful consideration. Intermediate bases distribute and organize the support points.

Electrical access

The electrical box installed on the right remains accessible without having to remove the heat pump.

Airflow

The fan side is completely unobstructed.

An outdoor unit should not be installed in front of an obstruction simply because that location shortens the piping.

The mistakes we seek to avoid with a rooftop heat pump

A comparable installation can become problematic when certain details are overlooked.

Among the most common mistakes:

1. installing the equipment too low;
2. placing the heat pump directly in an area where snow accumulates;
3. blocking access to the service valves;
4. installing the fan facing an obstruction;
5. concentrating loads on the membrane;
6. leaving the piping or wiring without adequate protection;
7. choosing an unstable support;
8. forgetting the space required for defrosting;
9. reusing incompatible lines without verification;
10. installing the equipment based on what is easiest today rather than on future maintenance;

A professional HVAC installation is precisely about eliminating these unnecessary compromises.

An efficient machine cannot compensate for a poor installation

This Fujitsu Altair 700 delivers a performance rating of 27.5 SEER2, operates on R-32, and has an Inverter compressor capable of modulating its output.

All these features are appealing.

But no technical specification can compensate for:

• improper condensate drainage;
• an unstable support;
• an inadequate system vacuum;
• an improper flared connection;
• an incorrectly calculated line length;
• obstructed outdoor airflow;
• an inaccessible unit for servicing.

At AirGreen, we therefore consider the equipment and the installation as a single system.

Our AirGreen approach in Salaberry-de-Valleyfield

This Fujitsu AIRSTAGE Altair 700 heat pump installation in Salaberry-de-Valleyfield particularly illustrates how we work on projects where the outdoor unit must be installed on a roof.

We analyze the site first, then the machine.

We look at where snow may accumulate, how defrost water will drain, where the lines will run, how to protect the roof, and how a technician will be able to access the equipment several years after installation.

This is the same method we apply to our heat pump projects in Montreal, Laval, Longueuil, the North Shore, and the South Shore.

For the homeowner, the visible result is a properly installed Fujitsu on its support.

For us, the true result is an installation where the equipment can operate under the conditions for which it was designed, without the roof, snow, or accessibility becoming avoidable problems.