Installation of a MIDEA EVOX G3 central heat pump in Pointe-Claire, in Montreal’s West Island

In Pointe-Claire, a MIDEA EVOX G3 central installation in a narrow side passage where every connection had to remain accessible

This MIDEA EVOX G3 central heat pump installation in Pointe-Claire illustrates a challenge we frequently encounter in the West Island of Montreal: integrating a modern central system into an existing residence when the available outdoor space is limited and already occupied by several building services.

The photograph taken during our project shows the situation much more precisely than a simple technical sheet. The new outdoor unit is located along a facade covered with brown shingles, in a relatively narrow side passage. Two electrical enclosures are already installed on the wall. The refrigerant and electrical lines must reach the house in the same area. In the background, another outdoor unit can also be seen in the same alignment.

We therefore had to position the MIDEA EVOX G3 without turning this mechanical corridor into an inaccessible space.

The unit is installed on a raised metal structure, rather than directly on the ground. Its refrigerant connections are concentrated on the side of the cabinet, with insulation carefully maintained around the vapor line. The service panel remains accessible, as do the nearby wall-mounted electrical installations.

MIDEA documentation presents the EVOX G3 as a range of ducted inverter central heat pumps, designed in particular to modernize existing residential systems.

The photo shows an often-overlooked point: the service side of the heat pump must remain accessible

Advertising photos almost always show a heat pump from the front. At our Pointe-Claire project, the photo is interesting precisely because it shows the other side: the one where the connections, technical labels, and service access points are located.

This is where we find, in particular:

• refrigerant connections;
• the liquid line;
• the insulated vapor line;
• the electrical wiring;
• the technical panels;
• the nameplate;
• the warnings specific to the refrigerant used.

Therefore, this space must not be compressed to the point where future service becomes difficult.

An installation may appear very compact and tidy on the day it is completed, but if a technician ever has to dismantle a fence, remove a line, or move another installation simply to reach the service valves, the initial planning was inadequate.

At AirGreen, we aim to plan for this access from the initial positioning of the unit.

Limited clearance requires more precision, not less

In this side passage in Pointe-Claire, the distance between the heat pump and the façade is naturally limited.

This requires carefully checking the prescribed clearances, airflow around the coil, and access to the components.

The MIDEA EVOX G3 uses an outdoor design with horizontal discharge. MIDEA explains that the horizontal fan works with a vertical heat exchanger to achieve more uniform airflow across the heat exchanger and improve heat transfer efficiency.

Airflow therefore concerns more than just the space in front of the fan. The outdoor heat exchanger must also be able to receive the necessary air across its intake surfaces.

This is particularly important when multiple units are installed in a relatively narrow corridor.

The presence of another outdoor unit completely changes the placement strategy

Aligned behind the new EVOX G3, a second outdoor unit can be seen.

When two units are present in the same area, we cannot consider each machine separately.

We must verify that:

• the air discharged by one unit does not flow directly back toward the other;
• the technical access points for both units remain available;
• the prescribed clearances are maintained;
• neither unit blocks an essential maintenance area of the other;
• the supports and lines do not create a mechanical conflict.

This situation is common in Pointe-Claire, Dorval, Beaconsfield, Kirkland, and several areas of Montreal, where various HVAC systems have often been added to the home over the years.

The elevated support protects the heat pump's surroundings during the Montreal winter

The metal support visible in the photo also plays an important role during the cold season.

A central heat pump used for heating must regularly perform defrost cycles. When the frost accumulated on the heat exchanger melts, the water flows down to the base of the condenser.

If the unit is practically at ground level, this water can refreeze around the machine. Added to this are natural snowfall, accumulations caused by snow removal, and repeated temperature fluctuations.

By leaving a clear area beneath the EVOX G3, we improve the conditions around the unit during these cycles.

This clearance helps, in particular, to limit:

• ice directly under the unit;
• snow obstruction;
• constant contact between the base and wet ground;
• the difficulties of inspecting beneath the unit.

An EVOX G3 designed to continue heating when the temperature drops sharply

It is precisely in this winter context that the EVOX G3's features become interesting.

Page 3 of the MIDEA brochure describes continuous operation down to -30 °C. The manufacturer also indicates that, in tests conducted on a three-ton MIDEA system, up to 100% heating capacity was available at approximately -25 °C, with a COP of approximately 1.9.

MIDEA also explains that its compressor can use an intermediate-temperature vapor supply when conditions become very cold. The goal is to increase the amount of compressed refrigerant and support heat production.

For a Pointe-Claire residence, the ability to maintain heat output during cold periods is far more important than a simple efficiency figure obtained at a mild temperature.

A minimum operating temperature is not the same thing as a home's heating load

However, it remains essential to properly interpret the phrase “down to -30 °C.”

It indicates the system's ability to continue operating under certain conditions. It does not mean that an EVOX G3 of any capacity will be able to meet the needs of any home on its own down to -30 °C.

We must determine the building's actual heat load, taking into account, among other things:

• of its area;
• of its insulation;
• of air infiltration;
• of the windows;
• of the orientation;
• of the number of stages;
• of the design temperatures;
• of the air distribution network.

This is what makes it possible to choose a suitable capacity.

Several EVOX G3 capacities: the model name alone is not enough to determine the tonnage

The Pointe-Claire photograph allows us to identify the MIDEA EVOX G3 family, but the unit's complete model reference is not clear enough to publish its exact tonnage with certainty.

We prefer not to assign a capacity based solely on the apparent cabinet dimensions.

The specifications table presented on page 11 of the MIDEA brochure includes several combinations, from 18,000 to 54,000 BTU/h, with different efficiency ratings.

Among the documented configurations:

The range can therefore reach 19 SEER2, 12.5 EER2, 10.8 HSPF2, and a COP of 2.14 at approximately -15 °C, depending on the exact combination.

This variation explains why a quote should always identify the exact models of the outdoor unit and indoor unit, rather than indicating only “MIDEA EVOX G3”.

R-454B is clearly identifiable on the photographed machine

The side view of this installation also allows us to see the important safety labeling affixed to the cabinet.

The flame pictogram associated with A2L refrigerant is clearly visible.

MIDEA states that it has adopted R-454B for its EVOX range, with an announced global warming potential of 466.

This refrigerant change directly affects how our technicians must work.

Equipment using R-454B requires appropriate procedures and tools, particularly for:

• refrigerant connections;
• leak tests;
• evacuation of the circuit;
• commissioning;
• safety practices.

The label is therefore not simply a formality stuck to the side of the unit.

The piping loop visible on the job site is not an improvised detail

The insulated refrigeration line forms a significant curve at the base of the unit before joining the system.

A refrigeration copper tube must not be bent sharply to gain a few inches. We must maintain adequate bend radii and avoid deformations that could reduce internal flow or damage the insulation.

In a corridor as compact as the one in this Pointe-Claire residence, the physical management of the lines becomes particularly important.

We must manage to bring together:

a clean route, appropriate bend radii, service access, insulation protection, and a consistent final finish.

Two electrical boxes side by side: another visible constraint in the photo

The facade also has two electrical boxes immediately beside the installation.

They obviously cannot be blocked by the new system.

When equipment is added in an already occupied area, we must always identify what needs to remain accessible after our work. This includes a disconnect switch, a meter, a service entrance, a ventilation outlet, or another technical building component.

This type of inspection avoids having to move a heat pump unnecessarily a few years later.

Indoors, the EVOX G3 must be adapted to the existing ductwork to provide the expected comfort

A central system is first and foremost an air circulation system

The most photogenic part of a central heat pump is generally its outdoor condenser.

However, much of the actual performance depends on what happens in the ducts.

The indoor unit must move enough air through:

• the return;
• the filter;
• the coil;
• the plenum;
• main ducts;
• branch connections;
• the grilles in each room.

A properly sized heat pump can be limited by an overly restrictive duct system.

That is why, when replacing a central system in Pointe-Claire or elsewhere in Montreal, we should never analyze only the old rated capacity.

Computational Constant Airflow 2.0 and up to 1.2 in. of static pressure in MIDEA's examples

The brochure's page 8 details the Computational Constant Airflow 2.0 technology.

MIDEA shows examples where an airflow of 1,200 CFM is maintained at different static pressures, up to 1.2 in. of water column under the conditions presented.

The system also offers up to 60 levels of airflow customization. The manufacturer indicates that the motor can adjust its power and speed to respond to changes in resistance throughout the duct system.

This capability is interesting when a new unit must be connected to existing ducts.

However, it does not eliminate the need to correct a truly inadequate duct system. A return that is too small is still too small.

Block N Lock: an indoor unit designed for challenging mechanical spaces

The EVOX G3 is distinguished by more than just its condenser.

Its air handler features a modular design called Block N Lock. Page 6 of the documentation illustrates several orientations: vertical upward or downward, horizontal left or right, as well as low-boy configurations when height is limited.

This is a very useful feature in existing homes in Pointe-Claire, Dorval, Kirkland, Beaconsfield, Montreal, Laval, or Longueuil, where the mechanical room may not have been designed for the dimensions of a new unit.

Widths compatible with several older furnaces

MIDEA indicates indoor units approximately 14.5 to 21.5 inches wide, close to sizes commonly used with residential furnaces.

The platform also includes, depending on the application, an indoor unit that can accommodate a 115 V or 208/230 V power supply.

These features can simplify a retrofit, but they do not guarantee a replacement without modifications.

We must always check the plenum, return, drain, electrical system, and space intended for the filter.

Up to 25 kW of auxiliary heating depending on the configuration

The platform can accommodate a set of three-stage auxiliary electric heat, up to 25 kW depending on the selected capacity. MIDEA indicates that these stages can be activated and adjusted according to temperature needs.

In Quebec, this setting deserves careful attention.

We aim to let the heat pump operate for as long as it is practical and use electric backup heat when the heating load genuinely requires it.

An incorrect configuration can unnecessarily activate the electric resistance heaters and increase consumption.

485 communication, 24 V thermostat, and wireless options

The EVOX G3 supports several control methods.

MIDEA specifically presents:

• the communication mode 485;
• the use of certain 24 V thermostats;
• Sub-1 GHz wireless communication modules for certain configurations;
• automatic identification of the control mode.

These options appear on page 7 of the documentation.

This flexibility is particularly useful when a renovation makes it difficult to run new wires to the thermostat.

1-, 2-, or 4-inch MERV 13 filtration

The EVOX G3 system can also be paired with a filtration module compatible with 1-, 2-, or 4-inch MERV 13 filters.

According to MIDEA, this filtration can further reduce the amount of dust, pollen, particles, and dander circulating toward the coil.

A higher-performance filter must nevertheless be properly sized.

A high MERV rating installed on a small filter surface can create excessive resistance. We therefore need to consider both filtration quality and static pressure.

SmartHome: inverter operation becomes easier to monitor

With the compatible MIDEA communicating thermostat and the SmartHome app, the documentation presents various functions: scheduling, comfort management, consumption monitoring, diagnostics, and certain software updates.

This information is useful for a homeowner switching from an older furnace to an inverter system.

An inverter unit can run for a long time at low output. This does not necessarily mean that it consumes more or cannot reach the set temperature. Modulation is specifically intended to reduce abrupt fluctuations and frequent restarts.

LogisVert in 2026: eligibility depends on the exact combination

In Quebec, Hydro-Québec requires heat pumps installed since November 26, 2025, to be ENERGY STAR certified to qualify for the Heat Pump measure of the LogisVert program. When the other conditions are met, the current incentive is $50 per 1,000 BTU/h at -8 °C for an ENERGY STAR heat pump, and $120 per 1,000 BTU/h at -8 °C when it is also rated ENERGY STAR - Cold Climate.

The MIDEA brochure, for its part, indicates that the range presented exceeds the ENERGY STAR Most Efficient specifications shown in the document.

However, this does not automatically allow us to declare the subsidy amount for this Pointe-Claire installation.

We must verify the exact combination of indoor and outdoor models, its applicable certification and its recognized capacity at -8 °C. The LogisVert amount is calculated based on this capacity, not simply on the unit's commercial tonnage.

Mistakes to avoid in an installation similar to the one in Pointe-Claire

Trapping the service side against a wall

The photo shows why real access to the connections and panels must be maintained.

Bending the refrigerant lines too tightly

A compact layout does not permit sacrificing proper bend radii.

Blocking existing electrical equipment

Electrical cabinets and disconnect switches must remain accessible after the work is completed.

Underestimating the interaction between multiple outdoor units

When two units are aligned in the same passage, their clearances and airflow must be considered together.

Installing a cold-climate unit too close to the ground

Defrost cycles and winter accumulation must be part of the design from the outset.

An installation where the important work is found precisely in the details visible from the side

Our Pointe-Claire installation is interesting because the photo does not show only the elegant exterior of a new heat pump.

It highlights the elements that truly determine the quality of an HVAC installation: connections, insulation, piping loops, the service side, the support, the space between the unit and the building, as well as the proximity of electrical equipment.

The MIDEA EVOX G3 provides inverter technology suited to central systems, very-low-temperature heating capacity, R-454B refrigerant, advanced airflow control and several indoor integration options.

At AirGreen, our role is to ensure that all these technical features are supported by an outdoor and indoor installation that makes sense.

This is the same approach we apply to our central heat pump projects in Pointe-Claire, Montreal, Laval, Longueuil, the North Shore and the South Shore: looking at the house as a whole, planning for future maintenance, and never assuming that a heat pump is properly installed simply because it starts up on the day it is commissioned.