Installation of an ELIOS R454B central heat pump in Noyan, Montérégie

A compact outdoor installation adapted to a property where every clearance detail mattered

In Noyan, in Montérégie, our AirGreen team installed a ELIOS central heat pump operating with R454B refrigerant on a property whose exterior layout presented several practical constraints. The available space was located between two sections of the building, near a downspout, an eave, vinyl siding, and a masonry wall.

This type of environment requires much more than simply securing the outdoor unit. A position must be selected that facilitates airflow, protects the unit from snow accumulation, limits vibrations transmitted to the structure, and provides reasonable access for future HVAC maintenance.

In the photo of this installation, the ELIOS outdoor unit is mounted on a metal wall bracket, above ground level. This approach directly addresses the climatic realities of Noyan and the Greater Montreal area: windblown snow, ice, meltwater, fallen leaves, and moisture around the foundation.

Why install the outdoor unit on a wall bracket?

Mounting the unit on a wall bracket is not purely an aesthetic choice. In this project, it made it possible to keep the unit at an appropriate height while making effective use of a narrow area alongside the masonry.

A raised installation can offer several benefits:

• reduced risk of snow blocking the air intake or discharge;
• protection against water accumulation near the foundation;
• easier clearance beneath the unit;
• reduced contact with the ground, grass, and debris;
• optimal use of a property where ground space is limited;
• more convenient access to the refrigeration and electrical connections.

The choice of support must nevertheless take into account the actual weight of the equipment, the composition of the wall, and the vibrations produced during operation. A central heat pump must never be installed on an improvised or undersized fastening. The anchors, metal arms, and support points must form a stable assembly capable of withstanding start-up cycles, winds, and winter conditions.

A fastening made on a section of masonry

In this installation in Noyan, the brick wall was a more suitable surface for mounting the support than the adjacent vinyl siding. Masonry allows for a rigid fastening when it is properly assessed and drilled.

Our technicians must, among other things, avoid:

• weakened mortar joints;
• cracked or damaged bricks;
• areas too close to an edge;
• anchors that could damage the building envelope;
• a position that would unnecessarily transmit vibrations to a sensitive room.

The support visible beneath the unit consists of two arms reinforced with diagonal sections. This geometry distributes the load against the wall and keeps the unit away from the masonry. The space behind the equipment is essential to allow air to circulate and to provide access to the components during an inspection or repair.

A narrow location between several building elements

The selected area is located near a vertical downspout, two building sections, and various roof overhangs. These elements had to be considered even before drilling began.

A downspout may seem harmless, but it carries a significant amount of water during heavy rain and snowmelt. The outdoor unit must be positioned so that it does not receive this water directly. A leak or overflow from the gutter could cause ice to form on or around the heat pump.

Roof overhangs deserve the same attention. They can partially protect the unit, but they can also concentrate water runoff in one specific location. In winter, icicles or sheets of snow may also fall from the roof. We therefore assess the likely behavior of water and snow, not just the visible clearance on the day of installation.

Outdoor airflow that must not be overlooked

The outdoor unit of a heat pump exchanges heat with the surrounding air. Its performance therefore depends on adequate airflow around the heat exchanger and in front of the fan.

Even when an appliance appears to physically fit in a space, that does not automatically mean the space is suitable. A unit placed too close to a side wall, fence, soffit, or other equipment may draw in some of the air it has just discharged. This recirculation can reduce performance, lengthen operating cycles, and complicate defrosting in winter.

In this project, the unit’s ventilated face remains completely unobstructed. The fan can discharge air directly into the open space, with no immediate obstacle in front of the grille.

We always comply with the clearances prescribed by the manufacturer for the installed model. These distances may vary from one series to another; they should therefore not be determined based on a general rule or the appearance of the appliance.

R454B Refrigerant: A New Generation of HVAC Equipment

The mention R454B refers to the refrigerant used by the system and not, on its own, to the heat pump’s capacity. This distinction is important for homeowners comparing several quotes.

R454B is used in a new generation of heat pumps and air conditioners to reduce the climate impact associated with refrigerants. Its use also entails specific requirements for handling, tools, installation, and commissioning.

R454B belongs to the category of mildly flammable refrigerants, commonly designated A2L. This does not mean that a properly installed appliance poses any particular danger to the occupant. Rather, it means that technicians must follow procedures adapted to this refrigerant:

• use compatible instruments;
• carefully check the tightness of the connections;
• thoroughly evacuate the circuit;
• comply with the charge limits and manufacturer’s requirements;
• maintain a safe work area;
• follow the prescribed recovery and commissioning procedures.

At AirGreen, we view the refrigerant change as a technical evolution that requires training, precision, and a complete understanding of the equipment. It is not enough to connect a new machine using the same practices used with older systems.

A central heat pump is not limited to the unit visible outdoors

The photograph primarily shows the ELIOS outdoor unit, but a central heat pump installation comprises several components that work together.

Depending on the building’s configuration, the indoor system may include an air handler, a coil, a compatible furnace, a central fan, a thermostat, and a duct network. The final result depends on the balance among all these components.

Before installation, we must verify or determine:

• the required heating and cooling capacity;
• the condition of the existing ducts;
• the available airflow;
• the building’s electrical capacity;
• compatibility between the indoor and outdoor components;
• the refrigeration line size;
• the auxiliary heating strategy;
• the thermostat location;
• condensate drainage in cooling mode.

A quality outdoor unit cannot compensate for a duct system that is too restrictive, an undersized filter, or an improperly configured fan. That is why we approach every HVAC installation as a complete system rather than simply replacing an outdoor box.

BTU capacity must be calculated, not guessed

The exact capacity of this unit cannot be read from the photograph. We therefore avoid arbitrarily assigning it a capacity of 24,000, 30,000, 36,000, or 48,000 BTU based on its exterior dimensions.

Two appliances that look similar may offer very different capacities and features. Sizing must be based on the property’s heating and cooling needs and the exact technical data for the installed combination.

Factors that influence the calculation include:

• the heated floor area;
• the insulation level;
• the building’s airtightness;
• the number and quality of the windows;
• the property’s orientation;
• ceiling height;
• the layout of the floors;
• basement heat loss;
• wind exposure;
• the region’s design outdoor temperature.

An undersized heat pump may run continuously without maintaining the desired temperature during very cold periods. An oversized unit may produce excessively short cycles, less stable humidity control, and less uniform air distribution.

At Noyan, as in Montréal, Laval, Longueuil, on the North Shore and the South Shore, sizing must take Quebec’s winter conditions into account, not just summer cooling needs.

The importance of refrigeration piping

The pipes between the outdoor unit and the indoor system carry the refrigerant. Their diameter, length, insulation, and tightness directly affect the heat pump's operation.

During an installation, we pay particular attention to the following:

• using the diameters required by the manufacturer;
• protecting the insulation from the weather;
• forming clean, even bends;
• preventing rubbing against the masonry;
• flared or brazed connections made according to the system design;
• leak testing;
• vacuuming before commissioning;
• adding refrigerant only when required by the total length.

On this property, the connections were arranged behind and beneath the unit to reduce their exposure and maintain a neat visual result. A clean installation also makes future inspections easier: a technician can follow the route of the pipes without having to dismantle a buildup of cables or poorly secured materials.

Vibration and noise management

The noise from a heat pump does not depend solely on the decibel rating published by the manufacturer. How the unit is installed can amplify or reduce vibrations.

With a wall-mounted support, we must pay particular attention to mechanical transmission to the structure. The fasteners must be secure, but the unit must also be properly seated on its support points. Anti-vibration components may be used depending on the configuration and applicable requirements.

We also check that:

• the chassis does not directly touch the wall;
• no pipe vibrates against the brick;
• the unit's panels are properly closed;
• the support is level;
• the connections are not under stress;
• the nearby downspout cannot strike the unit.

These details are particularly important when a bedroom or living space is located on the other side of the wall.

Commissioning: the step that confirms installation quality

Once the mechanical and electrical work is complete, commissioning verifies the system's actual performance.

Depending on the equipment, our checks may include:

1. confirming the electrical voltage;
2. inspecting the safety devices and wiring;
3. starting the system in heating and cooling modes;
4. checking the indoor fan;
5. measuring supply and return temperatures;
6. confirming condensate drainage;
7. observing the prescribed pressures and parameters;
8. checking for vibrations;
9. testing the controls and thermostat;
10. the explanation of how it works to the homeowner.

This step helps identify an issue before it turns into a service call. It also confirms that the indoor and outdoor components are communicating properly.

This Noyan project illustrates our custom installation approach

A discreet result despite complex architecture

The ELIOS unit was integrated into an outdoor space where brick, foundation, vinyl siding, roofing, and stormwater drainage meet. Despite this irregular geometry, the result remains compact and functional.

The chosen location makes it possible to:

• to keep the outdoor fan clear;
• to elevate the unit;
• to use a sturdy mounting surface;
• to keep the connections grouped together;
• to preserve circulation space around the building;
• to avoid placing the unit directly on the ground.

This type of project shows why a site visit, precise measurements, and an analysis of the building envelope remain essential. The best location is not always the most obvious at first glance.

Mistakes to avoid during a similar installation

For a central heat pump installed in a tight area, several mistakes can reduce the system’s lifespan or performance.

Installing the unit too close to an obstacle

Insufficient clearance impairs heat exchange and complicates maintenance. The clearances specific to the selected ELIOS model must be checked.

Neglecting snow accumulation or roof runoff

A unit placed beneath a runoff area may be exposed to water, ice, or a heavy snow load.

Attaching the support only to decorative siding

Vinyl, aluminum, or certain siding materials are not necessarily load-bearing structures. The anchors must reach an appropriate support.

Guessing the capacity based on the old equipment

Replacing an old heat pump with a new unit of the same capacity is not always the best solution. The building’s needs may have changed, and the old system may already have been improperly sized.

Automatically reusing existing lines

The diameters, insulation condition, internal cleanliness, and compatibility with the new refrigerant must be verified. The fact that a line is already in place does not guarantee that it is suitable for the new R454B appliance.

Forget access to the service

The panels, valves, and electrical components must remain accessible. An installation tightly positioned against several walls can make a simple repair unnecessarily complicated.

Recommended maintenance after installation

To preserve the performance of an ELIOS central heat pump, the owner should regularly inspect the area around the outdoor unit.

It is recommended to:

• clear away snow without striking the unit;
• remove leaves and vegetation from around the coil;
• monitor abnormal ice buildup;
• check that the gutter and downspout are not leaking;
• replace or clean the indoor filter according to the recommendations;
• never completely cover the unit during the winter;
• schedule an inspection when the system produces an unusual noise or has difficulty maintaining the temperature.

A light layer of frost is normal in heating mode. The heat pump periodically performs a defrost cycle. However, a persistent layer of ice that blocks the coil should be professionally inspected.

Rebates and eligibility: always verify the exact combination

Some heat pumps may qualify for financial assistance, particularly when they meet the criteria of a current program. However, eligibility cannot be confirmed solely based on the ELIOS brand or the R454B designation.

You generally need to verify the complete combination of the indoor and outdoor model numbers, the applicable certification reference, the recognized capacity, and the program conditions at the time of purchase.

We therefore recommend never basing a financial decision on a general verbal estimate. Quotation and billing documents must clearly identify the proposed equipment.

AirGreen serving Noyan and Greater Montreal

This ELIOS R454B central heat pump installation in Noyan reflects our approach: examining the actual location, anticipating winter constraints, protecting airflow, and carrying out a complete commissioning.

We install and replace HVAC systems in Montreal, Laval, Longueuil, on the North Shore, on the South Shore, and in several municipalities in Montérégie. Each building has a different combination of ductwork, electrical capacity, insulation, and architectural constraints.

Our work consists of choosing and installing a system suited to these realities, rather than applying the same solution to every property.