Installation of a Sharp Eco Inverter wall-mounted heat pump in Saint-Laurent

A flat roof construction site designed to last

At AirGreen , we have just completed the installation of a Sharp Eco Inverter wall-mounted heat pump for a rental building in the Saint-Laurent sector (Montreal) . The outdoor condenser is positioned on the gravelled flat roof , an environment that requires rigorous methodology: membrane protection, load management, air circulation, safety clearances and maintenance access. Our intervention highlights what we do every day: deliver a safe, clean HVAC installation perfectly adapted to the Montreal climate .

From the planning stage, we evaluated the ideal route for the refrigeration lines and wiring between the indoor and outdoor units. The goal: reduce pressure losses, limit bends, protect the pipes from UV rays and frost, and ensure a neat appearance both inside and out. The result is a stable, quiet, and efficient system, ready to provide comfort in both heating and cooling.

Why the Sharp wall-mounted heat pump is an excellent choice in Montreal

The wall-mounted heat pump is a must-have in many homes in Montreal, Laval, Longueuil, on the South Shore and the North Shore thanks to its high efficiency and installation flexibility . Sharp's Eco Inverter range is distinguished by:

• variable speed technology that continuously adjusts power and reduces electricity consumption;

• discreet operation , ideal for living rooms;

• even air distribution thanks to the design of the blower;

• reliability in cold climates when commissioning and defrosting are configured according to the rules of the art.

In the chosen configuration, the interior head serves a main living space. Typical capacities for such a unit are between 12,000 and 18,000 BTU , a relevant sizing for open spaces such as Montreal living room-kitchen. Comfort is guaranteed in both summer and winter, with fine modulation that avoids jolts and temperature variations.

Design and roof mounting: stability, watertightness and silence

The Sharp outdoor unit sits on a galvanized steel frame attached to anti-vibration feet to:

• protect the roof membrane and distribute the loads;

• limit the transmission of vibrations to the structure;

• raise the condenser above snow and runoff water;

• maintain sufficient clearances around the fan for optimal air circulation.

We plan service paths around the unit to facilitate maintenance (exchanger cleaning, seasonal checks). The fasteners are sized to withstand the gusts and wind loads specific to the Saint-Laurent plateau, and the metal elements are treated against corrosion .

Refrigeration path and power supply: cleanliness and compliance

The refrigerant connections (liquid/gas) are thermally insulated along their entire length and capped as soon as they become visible. The path follows a direct route to the inner head to minimize:

• the number of elbows (better compressor efficiency);

• heat losses in heating mode;

• the risks of infiltration (all crossings are sealed).

The power supply includes an accessible proximity disconnect switch , compliant with RBQ/CSA requirements. The communication cable is separated from the power lines to avoid interference. Condensate is managed by gravity with a controlled slope; when pumping is necessary, we install a condensate pump with a safety tank and alarm. In this project, gravity flow was preferred, which simplifies maintenance and limits wear parts.

Execution details that make the difference

• Optimized defrosting : In heating mode, the unit periodically enters defrosting mode. We calibrate these cycles to prevent ice buildup under the unit and preserve the membrane thanks to a protective mat under the drain area.

• Cable Management : Harnesses are secured with UV clamps and sleeved at potential abrasion points.

• Water drainage : a slight slope of the support promotes flow and prevents stagnation near electrical parts.

• Maintenance access : clearance provided on the exchanger side and electrical box side for reading pressures, leak testing, adding charge if necessary.

Commissioning and performance checks

A deep vacuum is applied before opening the valves to ensure a moisture- and air-free circuit. Checks include:

1. Nitrogen leak test ;

2. Vacuum draw to the required threshold;

3. Checking the load currents and voltages;

4. Measurement of supply/return temperatures to validate the delta T in heating and cooling;

5. Setting user functions (speeds, shutters, night mode).

These steps determine the system's durability and energy performance . A well-commissioned device offers controlled consumption and a stable temperature, even during cold peaks.

Interior aesthetics and comfort of use

Inside, the wall head is placed on a metal mounting plate with anti-vibration mounts . The white cover of the connections fits in with most decors. We ensure:

• position the air outlet so as to sweep the living area without blowing directly on the occupants;

• clear the top of the unit (at least 10–15 cm) for good air intake;

• avoid obstacles (rods, cornices, high furniture) which would impair diffusion.

The customer benefits from simple control (remote control) and, if desired, a Wi-Fi module to program temperatures and schedules. In summer, the dehumidification function improves perceived comfort while limiting consumption.

HVAC Maintenance: Maintaining Efficiency Year After Year

An annual maintenance is recommended, ideally in the spring. Our service includes:

• cleaning of filters, coils and tank ;

• checking pressures and defrost cycle;

• checking connections (tightening torques, terminal blocks);

• inspection of the roof support (condition of the feet, screws, membrane);

• energy assessment with usage advice.

In addition to air quality , this maintenance extends the life of the compressor and maintains seasonal performance , which determines eligibility for certain financial assistance . Our team supports owners with the procedures applicable in Greater Montreal (Montreal, Laval , Longueuil , South Shore , North Shore ).

Common Mistakes to Avoid (and How We Prevent Them)

• Undersizing or oversizing : we carry out a simplified load calculation in order to adjust the capacity (BTU) to the thermal reality of the housing.

• Too long connection path : we optimize the length and check the manufacturer's limits (length/height) to preserve the COP.

• Absence of disconnector or inaccessible position: always present, visible and reachable .

• Support directly on the membrane : prohibited. We use anti-vibration feet and suitable interfaces.

• Hazardous condensate drainage : slopes respected, insulation against frost in exposed sections.

Results: comfort, silence and savings

As soon as it was put into service, the occupants noticed:

• even blowing and rapid temperature rise ;

• a contained noise level of the condenser thanks to the anti-vibration support;

• smoothed consumption via the inverter, favorable to savings compared to electric baseboards.

Beyond immediate comfort, the installation increases the energy value of the building while preparing for the future: modularity, compatibility with good efficiency practices and simplified maintenance .

Summary sheet

AirGreen, your HVAC partner in Greater Montreal

We support building owners and managers in Montreal, Laval, Longueuil, the South Shore, and the North Shore . Our promise: clean, compliant, and durable installations , meticulous commissioning , and maintenance monitoring that protects your investment. Do you have a flat roof or a constrained urban context? We design a custom HVAC installation that is as reliable as it is aesthetically pleasing.