Installation of a MIDEA EVOX G3 central heat pump in Saint-Michel

In Saint-Michel, a central installation designed for Quebec winters and a very real outdoor space

At this Saint-Michel project, we installed a MIDEA EVOX G3 central heat pump in an environment where quality workmanship depended on more than just choosing the equipment. We also had to work with the available outdoor space, the proximity of the wall, the equipment already present around the mechanical area, and, above all, anticipate what happens beneath a heat pump when it operates in heating mode during winter.

The project photo clearly illustrates this reality. The MIDEA outdoor unit is installed on a raised, self-supporting metal frame set on a concrete surface. The condenser therefore does not sit directly on the ground. Its large front fan remains completely unobstructed, while the refrigerant and electrical connections are grouped on the side of the unit where they remain accessible.

This installation choice is particularly relevant for a central heat pump used in low temperatures. In winter, the unit must be able to breathe, drain the water produced during defrost cycles, and remain sufficiently clear of snow. In a yard or service area where space is limited, every centimetre must be used logically.

The MIDEA EVOX G3 belongs to Midea's new generation of Inverter central systems. The technical documentation presents a range designed to operate down to -30 °C, with low-temperature heating performance that is one of this platform's main selling points.

An elevated outdoor heat pump: a choice that goes far beyond appearance

The most obvious detail of this Saint-Michel installation is the support.

We did not simply place the unit on a slab at ground level. The condenser is installed on a metal structure that gives it considerable clearance. The feet rest on the existing surface, and the unit itself is secured to the support.

For a central heat pump installation in Montreal or nearby areas, this elevation provides several practical benefits.

It helps in particular to reduce the risk of the bottom of the unit quickly becoming surrounded by snow during heavy accumulation. It also leaves space beneath the condenser so that the water produced during defrosting can drain away rather than immediately remaining trapped beneath the machine.

When we install a heat pump intended to provide heating at very low temperatures, we think about the situation in January, not just the appearance of the site in summer.

Defrosting is a reality that must be anticipated from the installation stage

A heat pump extracts heat from the outdoor air in winter. When conditions are cold and humid, frost can form on the outdoor heat exchanger.

The system then periodically initiates a defrost cycle to remove this accumulation. This process produces water.

If a heat pump is placed very close to the ground without considering how this water will drain, ice can gradually accumulate beneath the unit. This situation can become particularly problematic after several freeze-thaw cycles.

At the site photographed in Saint-Michel, the space beneath the MIDEA EVOX G3 is clearly visible. The stand keeps the machine above the concrete surface while maintaining access around the base.

It is precisely these details that distinguish an installation designed for occasional seasonal operation from one designed to serve as a primary or significant central heating system during the Quebec winter.

A front-discharge condenser well suited to restricted spaces

The exterior design of the EVOX G3 is also interesting.

Unlike some traditional central heat pumps whose fan exhausts air vertically upward, the MIDEA EVOX G3 uses a front horizontal discharge.

Midea explains in its documentation that the outdoor unit combines a horizontal fan with a vertical heat exchanger to promote more uniform air distribution across the heat exchanger. This design is intended in particular to maintain good heat exchange when the outdoor temperature drops.

In the photo from Saint-Michel, this advantage is easy to understand.

The large fan is oriented toward the open space in front of the unit. The air is not directed toward the block wall behind the machine. This configuration can be useful when the condenser must be installed alongside a building and available space is limited.

Naturally, we must always respect the clearances specified by Midea for the exact combination installed. A photo alone is never sufficient to establish or validate all of a project's regulatory clearances.

A compact installation despite several constraints around the equipment

The environment visible in this photo is not completely empty space.

On the left is a hose reel. Electrical equipment is already present on the wall. On the right, blocks and a relatively nearby physical boundary are also visible.

This means that the heat pump's position had to be chosen to avoid making the space unusable while keeping the unit's functional areas accessible.

For this type of project, we look in particular at:

• fan clearance;
• access to the service panels;
• the routing of the refrigerant lines;
• the electrical connection;
• the drainage of defrost water;
• the stability of the structure;
• future HVAC maintenance;
• the obstacles around the unit.

The best location is therefore not always the one where the condenser fits most easily. It is the one that remains practical several years after installation.

MIDEA EVOX G3: a complete family of Inverter central heat pumps

It is important to specify that the name EVOX G3 does not correspond to a single capacity.

Midea's documentation presents several systems ranging from approximately 18,000 to 54,000 BTU/h, with combinations suited to different residential needs. Depending on the capacity and combination selected, performance can reach up to 19 SEER2, 12.5 EER2, and 10.8 HSPF2.

Midea's technical table lists several Extreme Heat systems, including:

• 18,000 BTU with MAUSE-H18B-2A and MO1HE-H18B-2A;
• 24,000 BTU with MAUSE-H24B-2A and MO1HE-H24B-2A;
• 30,000 BTU with MAUSE-H30B-2A and MO1HE-H30B-2A;
• 36,000 BTU with MAUSE-H36B-2A and MO1HE-H36B-2A;
• 48,000 BTU with MAUSE-H48B-2A and MO1HE-H48B-2A;
• 54,000 BTU with MAUSE-H60B-2A and MO1HE-H60B-2A.

The photo provided for the Saint-Michel project does not allow us to read the nameplate clearly enough to honestly confirm the exact installed capacity. We therefore prefer not to invent a capacity.

This is an important distinction for our readers: two systems bearing the name EVOX G3 may have different performance and capacities.

Heating performance that explains the EVOX G3’s appeal in Quebec

Cold-weather heating is one of this platform’s main strengths.

Midea specifies continuous operation down to -30 °C for the Extreme Heat range. The documentation also states up to 100% heating capacity at -25 °C, with a COP that can reach approximately 1.9 under the conditions specified by the manufacturer.

This performance is directly related to the compression technology used by Midea.

The manufacturer explains that in extreme cold conditions, the compressor uses intermediate-temperature vapor injection to increase the amount of compressed refrigerant and support heating capacity.

For a homeowner in Saint-Michel, Montreal, Laval, Longueuil, on the North Shore or the South Shore, these low-temperature figures should receive more attention than a simple nominal BTU number.

A heat pump intended for Quebec must be evaluated when conditions are difficult.

Efficiency ratings that vary according to the installed tonnage

Efficiency ratings are not identical across the entire range.

In the Midea table, the 18,000 BTU system is listed with a SEER2 of 19, an EER2 of 12.5, and an HSPF2 of 10.1. The 24,000 BTU system reaches 18.6 SEER2 and 10 HSPF2. For 30,000 BTUs, Midea lists 17.2 SEER2 and 10.8 HSPF2. The 36,000 BTU system reaches 17.7 SEER2 and 10.0 HSPF2.

The higher capacities of 48,000 and 54,000 BTUs are listed at 17.5 SEER2 and 9.5 HSPF2 in the combinations presented.

This is why we always emphasize sizing.

Installing a larger heat pump solely because it has more BTUs is not a valid strategy. The equipment must match the building’s heat loss and the airflow that the ductwork can actually carry.

Behind the condenser visible in the photo: all the work of a true central HVAC system

The ductwork remains a decisive factor in the final result

A MIDEA EVOX G3 central heat pump never works alone.

The outdoor unit is connected to an indoor air handler, which must distribute heating and cooling to the various rooms through existing or newly installed ducts.

An excellent condenser connected to poor ductwork can produce mediocre results.

We must therefore check the available airflow, duct dimensions, returns, filters, and the system's static pressure.

Computational Constant Airflow 2.0: a particularly useful feature for renovations

Midea equips the EVOX G3 with its Computational Constant Airflow 2.0 technology.

The manufacturer states that the blower can adjust its output to maintain airflow despite changes in system resistance. The documentation illustrates operation up to approximately 1.2 in. of water column static pressure and mentions up to 60 airflow adjustment levels.

This flexibility can be useful in an existing home, where the ductwork is not necessarily identical to that of a new construction.

For example, static pressure can change when using a thicker filter or when the ductwork includes more restrictions.

The goal is not to compensate for poor ductwork with additional capacity. A significantly undersized duct must be corrected when necessary. But finer control gives us more flexibility to adjust the system to the actual building.

A modular air handler for challenging mechanical spaces

The EVOX G3 also uses a modular interior design called Block N Lock.

Midea provides up to six different orientations: upward airflow, downward airflow, horizontal right, horizontal left, and various low-boy configurations.

This feature is important when replacing an old furnace or a central unit in a finished basement.

We regularly encounter situations where:

• access to the mechanical room is narrow;
• the staircase does not allow a complete cabinet to be transported easily;
• the basement ceiling is low;
• the return air is located on the wrong side;
• the existing ductwork requires a particular orientation.

The EVOX G3's modular design allows it to better adapt to this type of renovation.

A width designed to facilitate the replacement of older furnaces

Midea also presents its air handler as an easier replacement solution for certain existing systems.

Depending on the capacity, the cabinets use widths of approximately 14.5 to 21.5 inches, similar to those of many residential furnaces. The EVOX G3 indoor unit can also be adapted to a 115 V or 208/230 V power supply depending on the configuration.

This does not mean that an installation can be completed without electrical work.

The outdoor unit has its own electrical requirements. Any auxiliary heating element must also be taken into account when calculating the panel load.

However, the ability to integrate more easily with existing infrastructure can reduce certain unnecessary modifications.

Auxiliary heating: an element to size with the heat pump, not afterward

Midea’s documentation provides for auxiliary electric heating elements of up to 25 kW, with controls that can operate in multiple stages.

Auxiliary heating is particularly important when a central heat pump replaces an old furnace.

At AirGreen, we do not choose this element solely based on “what fits” in the air handler. We must consider the following simultaneously:

the home’s heat loss,
the heat pump’s actual capacity at low temperatures,
the available electrical capacity,
and the desired heating strategy.

An oversized electric element may unnecessarily require a large power supply. An undersized element may not provide the desired support when demand reaches its maximum.

485, 24 V communication and integration with different thermostats

The control system is another interesting aspect of the EVOX G3.

Midea indicates compatibility with 485 communication mode or a traditional 24 V control, with automatic identification of the control type. The documentation also provides for different combinations with third-party thermostats.

For us, this flexibility is particularly relevant when replacing a system.

It is not always necessary to treat an existing home like a new construction. When the existing wiring and controls are compatible and in good condition, some parts of the infrastructure can sometimes be integrated into the new system.

With the Midea communicating thermostat and the SmartHome app, the manufacturer also provides schedule settings, consumption monitoring, and certain remote diagnostic and update functions.

MERV 13 filtration: worthwhile, but only if the ductwork can handle it

Midea indicates that its filtration module can accommodate 1-, 2- or 4-inch filters, including MERV 13 in the configuration described.

A better filter medium can capture more dust, particles, pollen and pet hair.

But we must follow a simple rule: more advanced filtration must not suffocate the system.

A filter increases resistance to airflow. We therefore check static pressure and airflow before recommending a significant filtration change.

This is exactly the kind of detail that affects comfort and equipment lifespan but is rarely visible in a photo of an outdoor installation.

R-454B: a new generation of refrigerant for the EVOX G3

Midea chose R-454B for this range of systems.

The documentation identifies R-454B as a refrigerant A2L and indicates a global warming potential, or GWP, of 466.

For the homeowner, this change is generally invisible.

For our refrigeration technicians, it is not.

The tools, handling, service procedures and work methods must comply with the requirements applicable to this new generation of equipment.

This is an additional reason to entrust the replacement of a central heat pump to a company that actually works with newer R-454B platforms.

Eligibility for subsidies must be confirmed using the exact model numbers

Midea's brochure indicates that the range exceeds the ENERGY STAR Most Efficient specifications presented by the manufacturer.

This is useful information when a homeowner compares high-efficiency equipment.

However, to determine actual eligibility and the potential amount of financial assistance such as LogisVert, we never rely solely on the name “MIDEA EVOX G3”.

We always verify:

• the exact outdoor model;
• the exact indoor model;
• the AHRI combination;
• the capacity;
• the installation date;
• the program's current criteria.

Because the precise tonnage of the unit photographed in Saint-Michel is not legible in the provided image, we do not attribute a precise subsidy amount to this project without that confirmation.

What the Saint-Michel photo teaches us about a good installation

This installation features several simple but revealing details.

The condenser is straight and stable. The fan has a large open area in front of it. The unit is raised high enough to create a genuine space beneath its base. The connections are grouped laterally. The equipment uses the available space without completely blocking the existing service area.

These installation decisions ultimately influence ease of maintenance and the equipment’s performance from season to season.

A modern central heat pump may have an excellent SEER2 and be capable of operating at -30 °C. If it is poorly positioned, improperly connected, or installed on an inadequate duct network, the homeowner will not get its full potential.

At AirGreen, our role is therefore not limited to installing a gray box outside a house.

We must make the heat pump, air handler, ductwork, auxiliary heating, thermostat, electrical supply, and the building itself work together.

This is the approach we apply to our central heat pump installations in Saint-Michel, Montreal, Laval, Longueuil, on the North Shore and the South Shore.

A properly installed EVOX G3 is above all a complete system

This Saint-Michel project is a good example of what a central system should strive for: equipment suited to the local climate, installed in a stable, accessible manner and designed around the site’s constraints.

The MIDEA EVOX G3 offers an appealing combination of Inverter technology, low-temperature operation, adjustable airflow, modern control options, and compatibility with a variety of renovation configurations.

But it is the decisions made on site that transform these technical specifications into real comfort.

We therefore place as much importance on the support visible in the photo as on the SEER2 indicated in the documentation. We look as closely at the route of the lines as we do at the compressor’s capacity. We check the indoor duct network just as carefully as the space left in front of the outdoor fan.

It is this attention to the whole that allows a HVAC system to remain logical and efficient for years.