A high installation on a brick façade where every clearance mattered
In Saint-Vincent-de-Paul, several residential buildings feature a configuration typical of Laval's established areas: brick façades, closely spaced windows, a side balcony or patio, limited ground space, and shared outdoor access. For this installation, the main challenge was not simply connecting a Hitachi airHome 800 wall-mounted heat pump. We had to find a location that protected the unit, preserved the use of the balcony, and ensured sufficient airflow around the condenser.
The project photograph clearly shows the solution chosen by our team: the outdoor unit was installed high on two metal wall brackets, directly against the masonry façade. It is positioned below the level of a window, near a balcony and an electrical disconnect box, without taking up ground-level passage space.
This type of HVAC installation in Laval requires more preparation than a conventional installation on a slab. The work must be carried out with suitable access equipment, the brackets must be perfectly aligned, and the anchor points must withstand the weight of the unit as well as the vibrations produced during heating, cooling, and defrost cycles.
Why the outdoor unit could not simply be placed on the ground
In this type of urban environment, a ground-level installation could have created several practical problems:
- reduced usable space near the balcony;
- obstruction of a passageway or storage area;
- increased exposure to accidental impacts;
- snow accumulation around the condenser;
- risk of leaves, dirt, or debris being drawn into the heat exchanger;
- ice formation beneath the unit during defrost cycles.
The wall bracket makes it possible here to completely free up the ground. This configuration is particularly useful when the outdoor space must continue to serve as a patio, corridor, or access area.
However, an elevated position does not mean that the unit can be installed at just any height. We must maintain realistic access to the service panels, refrigerant connections, fan, chassis drain, and electrical components. A heat pump placed too high or wedged beneath a structure can become unnecessarily difficult to maintain.
Work requiring ladder access in an occupied outdoor space
The presence of the ladder in the photo illustrates a practical site constraint: the technicians had to work at a considerable height in an area already furnished with a balcony, planters, and a large parasol.
Before beginning this type of work, we must organize the work area in order to:
- stabilize access equipment;
- protect surfaces and furniture;
- maintain a safe corridor;
- lift the unit without damaging it;
- allow technicians to work with both hands free;
- prevent tools or components from falling into an occupied area.
The outdoor unit of a wall-mounted heat pump must not be handled like a simple lightweight appliance. Even the compact models in the Hitachi airHome 800 series weigh approximately 91 lb, not including the supports or the tools required for connection. Lift planning is therefore an integral part of installation quality.
A parasol must never interfere with air discharge
The parasol visible near the heat pump is also a good example of a detail that may seem insignificant but deserves an explanation to the homeowner.
The outdoor unit draws air through its heat exchanger and expels it through the front fan. A parasol, canopy, decorative panel, tall planter, or furniture placed too close can deflect this airflow and promote recirculation.
To preserve system performance, we recommend keeping the space in front of the fan clear. Movable balcony accessories should be positioned so that they do not:
- block the front of the unit;
- touch the chassis;
- vibrate against the supports;
- retain snow near the condenser;
- deflect hot air during cooling;
- return cold air to the heat exchanger during heating.
Mounting a heat pump on a brick wall without creating vibrations
Installation on a brick façade requires a different assessment than installation on a concrete wall or foundation.
Brick veneer is not automatically a structural element capable of permanently supporting a concentrated mechanical load. The location of the anchors, the condition of the mortar, the wall thickness, and the structure behind the veneer must be taken into consideration.
For this heat pump installation in Saint-Vincent-de-Paul, the supports were installed with spacing that distributes the unit’s weight properly. The two horizontal arms support the chassis, while the vertical posts transfer the load to the wall.
Leveling also protects the refrigeration system
An improperly leveled support can have consequences beyond visual appearance. The outdoor unit must rest properly in order to:
- Promote drainage of the water produced during defrosting;
- Prevent twisting of the chassis;
- Limit stress on the copper connections;
- Prevent the fan from operating in a deformed housing;
- Reduce vibrations transmitted to the masonry.
We therefore check the level before final fastening, then a second time after the unit has been installed.
The piping must not become a source of resonance
Even when a compressor operates quietly, a copper pipe touching the brick can produce a noticeable hum in an interior room.
We pay particular attention to the following points:
- Maintaining insulation around the piping;
- No direct contact between the copper and the masonry;
- Sufficiently wide bends;
- Securing the harness without crushing it;
- Protection of the connections;
- No voltage between the unit and the wall penetration.
In the photo, the piping and wiring are routed toward the right side of the unit, near the electrical box. This arrangement reduces the number of visible penetrations and concentrates the technical components in one area.
The electrical disconnect located near the unit
The disconnect box installed to the right of the heat pump allows the unit’s power supply to be disconnected during service. It must be accessible while not obstructing the opening of the service panels.
An adequate electrical installation involves more than simply adding a circuit breaker. It must take into account the exact nameplate of the installed combination.
For the Hitachi airHome 800 series:
- The 9,000 and 12,000 BTU/h models have a minimum circuit ampacity of 14 A and a maximum protection of 25 A;
- The 18,000 and 24,000 BTU/h models have a minimum ampacity of 20 A and a maximum protection of 35 A;
- The rated supply is 230 V or 208–230 V, depending on the capacity.
These data serve as a reference, but the final circuit sizing must always follow the nameplate of the equipment actually delivered and the applicable electrical requirements.
What the Hitachi airHome 800 brings to this Saint-Vincent-de-Paul residence
A range offered from 9,000 to 24,000 BTU/h
The Hitachi airHome 800 is available in four main sizes. The nominal cooling capacities indicated by the manufacturer are 9,500, 12,500, 18,000, and 22,000 BTU/h, while the nominal heating capacities reach 12,000, 13,500, 21,600, and 25,400 BTU/h, respectively.
The photograph shows the compact outdoor chassis used by the 9,000 and 12,000 BTU/h versions. These two capacities share the same outdoor dimensions, approximately 33.46 in. wide, 25.59 in. high, and 11.73 in. deep. The exact capacity must nevertheless be confirmed on the nameplate, since the exterior appearance does not distinguish between these two combinations.
The series' technical specifications indicate a heating range down to -30 °C, heating capacity maintained at 100% at -20 °C, efficiency of up to a TRÉS2 of 26.5, and a region 5 CPSC2 of up to 9.7. The lineup uses R32 refrigerant.
Heating truly suited to Laval winters
For a home in Saint-Vincent-de-Paul, heating performance is just as important as summer cooling.
The compact versions in the lineup can continue to provide heat at very low temperatures:
9,000 BTU/h model
- up to 14,000 BTU/h at -15 °C;
- up to 12,000 BTU/h at -20 °C;
- up to 8,500 BTU/h at -25 °C;
- up to 5,500 BTU/h at -30 °C.
12,000 BTU/h model
- up to 15,200 BTU/h at -15 °C;
- up to 13,500 BTU/h at -20 °C;
- up to 10,500 BTU/h at -25 °C;
- up to 6,000 BTU/h at -30 °C.
These values show why the choice of a heat pump should not be based solely on its cooling capacity. Two units advertised in a similar category can have very different performance when the outdoor temperature drops below -15 °C.
Proper sizing remains essential
A larger heat pump is not automatically a better heat pump.
To determine the appropriate capacity, we consider, among other things:
- the area actually open to the indoor unit;
- the layout of the rooms;
- the number of floors;
- insulation quality;
- sun exposure;
- windows;
- ceiling height;
- air infiltration;
- the presence of a supplementary heating system;
- the desired temperature during cold periods.
An oversized unit can reduce dehumidification quality in summer. It can also cause short cycles and more noticeable temperature fluctuations. An undersized unit, on the other hand, may run continuously without meeting the home's load.
Inverter technology to prevent abrupt starts
Inverter technology allows the compressor to adjust its speed according to demand. Instead of operating only at full capacity and then stopping, the system can gradually reduce its speed as the temperature approaches the setpoint.
In a residence, this modulation contributes to:
- maintain a more stable temperature;
- reduce on-off cycles;
- improve comfort near the indoor unit;
- reduce sound variations;
- better control humidity;
- limit consumption peaks associated with restarts.
Quiet operation for a unit near windows
The small-chassis outdoor unit has a high nominal sound level of 52 dB(A). Indoors, the 9,000 and 12,000 BTU/h models can reach as low as 30 dB(A) in silent mode.
This data is particularly relevant here because the outdoor unit is located near windows. However, the actual sound level also depends on the installation.
A rigid support, suitable anchors, and properly insulated lines can make the difference between a quiet system and an irritating vibration transmitted to the wall.
FrostWash 3.0: a cycle to clean the indoor heat exchanger
The FrostWash 3.0 technology performs a three-step cycle:
- the coil is heated to help detach greasy particles;
- the heat exchanger is cooled until frost forms and traps certain dust particles;
- the ice melts and carries impurities toward the drain.
This feature helps keep the indoor heat exchanger cleaner. However, it does not replace filter cleaning or periodic inspection of the drain and fan.
Mold Guard 2.0 to reduce internal moisture after shutdown
A wall-mounted unit can retain moisture on its heat exchanger after operating in cooling mode. When this moisture persists, it can promote the development of odors and biological deposits.
The Mold Guard 2.0 function monitors conditions inside the unit even when it is turned off. When the system detects an environment favorable to mold, it heats the coil to dry it.
This feature is relevant during hot and humid periods in Laval, particularly when a heat pump operates several hours a day.
PM2.5 filtration and stainless steel prefilter
The Hitachi airHome 800 includes a PM2.5 activated carbon filter and a stainless steel prefilter. The carbon filter is intended in particular to reduce certain small particles and certain odors present in recirculated air.
However, it is important to understand the role of a wall-mounted heat pump: it primarily treats the air in the room where the indoor unit is installed. It does not replace a central ventilation system or a purifier covering the entire building.
Smart Eco, SleepSense, and airCloud Go control
The Wi-Fi interface connects the unit to the airCloud Go app. The owner can then control the heat pump remotely and schedule its operation.
Available features include:
- weekly timer;
- remote temperature adjustment;
- Smart Eco mode;
- SleepSense function;
- consumption estimation;
- display of certain error codes;
- FrostWash activation;
- integration with certain voice assistants.
The Smart Eco function uses a motion sensor to detect room occupancy. After a period of inactivity, the system may reduce its operation, then resume the initial setting when an occupant returns.
R32 refrigerant and commissioning precautions
The airHome 800 series uses R32 refrigerant, which has a lower global warming potential than several refrigerants used in previous generations of equipment.
Using R32 does not reduce the importance of the commissioning steps. We must always:
- make compliant refrigeration connections;
- perform a leak test;
- evacuate the system;
- confirm the piping length;
- check whether an additional charge is required;
- check operating temperatures;
- test the heating, cooling, and drainage.
Line diameters specific to each capacity
The 9,000 and 12,000 BTU/h models use 1/4-in. liquid and 3/8-in. gas connections.
Higher-capacity models use different diameters:
- 18,000 BTU/h: 1/4 in. and 1/2 in.;
- 24,000 BTU/h: 3/8 in. and 5/8 in.
This difference is critical when replacing an older system. Existing piping must never be reused solely because it already connects the same two locations. Its diameter, length, cleanliness, and condition must be checked.
Defrost water must remain under control
In heating mode, the outdoor heat exchanger may accumulate frost. The heat pump then temporarily reverses its cycle to melt the buildup.
The water produced flows beneath the unit. In this elevated installation, it is not at risk of directly burying the unit’s base, but it must still fall in a safe location.
Ice formation must be prevented:
- on the steps;
- in a passageway;
- in front of a door;
- on a ramp;
- above a lower balcony;
- near a foundation vulnerable to water infiltration.
Errors this installation helps avoid
A similar installation must be designed to prevent several common problems:
- Installing the unit in a space that is too narrow, without sufficient clearance for airflow.
- Anchoring the supports in weakened masonry.
- Underestimating the equipment’s weight during lifting.
- Placing the disconnect switch behind an inaccessible panel.
- Allowing the lines to touch the brick.
- Allowing balcony furniture to block the fan.
- Directing defrost water toward a traffic area.
- Choosing capacity based solely on floor area.
- Reusing old piping without checking its diameter.
- Neglecting future access for HVAC maintenance.
Eligibility for financial assistance must be confirmed before the work
Hitachi documentation specifies that the airHome 800 range may be eligible for several provincial incentives. However, this statement does not guarantee that every capacity and combination will automatically qualify for a subsidy.
Eligibility must be verified using:
- of the complete indoor model;
- of the complete outdoor model;
- of the AHRI reference or recognized certification;
- of the heating capacity at the required temperature;
- of the type of residence;
- of the program in effect on the installation date;
- of the invoice and requested documents.
We recommend carrying out this verification before finalizing the choice of equipment, not after its installation.
An installation representative of AirGreen’s work in Laval
This installation in Saint-Vincent-de-Paul shows that a wall-mounted heat pump project is about more than choosing a brand. The quality of the result also depends on the unit’s positioning, the strength of the supports, airflow, electrical connections, defrost management and accessibility for years to come.
At AirGreen, we carry out this type of HVAC installation in Montréal, Laval, Longueuil, the North Shore and the South Shore. Every building presents its own constraints: a narrow balcony, brick wall, condominium, shared passageway, rooftop, interior courtyard or elevated access.
In this project, the wall-mounted installation of the Hitachi airHome 800 preserved the outdoor space while keeping the unit off the ground and away from snow accumulation. The result is a compact, structured installation suited to the residence’s existing architecture.