Installation of a MIDEA EVOX G3 central heat pump in Saint-Clet, in Montérégie

In Saint-Clet, a MIDEA EVOX G3 installed high in an already occupied mechanical area

Some jobsite photos are particularly useful because they show what normally disappears once the work is complete. This is exactly the case with this MIDEA EVOX G3 central heat pump installation in Saint-Clet. The photograph was taken during the work: the refrigerant connections, line insulation, and some cables are still visible, while the outdoor unit is already firmly positioned on its support.

This intermediate stage provides a much better understanding of our work.

At this Saint-Clet residence in Montérégie, we did not have a large open area around the house. Another outdoor unit was already present on the left, a fence enclosed part of the yard, the facade was made of masonry, and the passage along the building had to remain usable. We therefore had to integrate the new MIDEA EVOX G3 central heat pump without simply adding another unit directly on the ground.

Our solution was to install the new condenser on a raised metal structure secured against the foundation. This arrangement frees up the ground, creates significant clearance beneath the heat pump, and places the unit in a position much better suited to winter use.

The EVOX G3 belongs to the range of MIDEA inverter ducted central systems, designed in particular to modernize existing heating and air conditioning installations.

A photo taken before the finishing work that shows the true anatomy of a central system installation

On a completed installation, homeowners usually see the condenser, a finish around the lines, and a clean electrical connection. They see much less of what happens between the time the unit is secured and the time we complete all the finishing work.

In this photo from Saint-Clet, the refrigerant lines still clearly lead to the service compartment. Part of their insulation is visible, and the electrical connections are still accessible.

It is precisely at this stage that several critical operations must be carried out accurately: connections, circuit verification, preparation for vacuuming, electrical inspection, and validation of communication with the indoor unit.

A beautiful exterior finish can never compensate for poor refrigeration circuit preparation. At AirGreen, we therefore consider these invisible steps to be a fundamental part of the HVAC installation.

Why raise the heat pump instead of placing it on a slab?

The answer appears almost directly in the photograph: the new unit would have occupied a large portion of the passage if it had been placed on the ground.

But the main reason is also climatic.

A central heat pump used for heating must perform defrost cycles during the winter. Moisture that freezes on the outdoor coil is periodically turned into water. This water must be able to drain beneath the unit.

By installing the EVOX G3 at a higher level, we create more space to:

• reduce the risks associated with snow accumulation;
• allow defrost water to drain away from the base of the unit;
• limit the progressive accumulation of ice directly beneath the condenser;
• keep the lower components accessible;
• avoid unnecessarily obstructing the passage along the house;
• keep the unit well separated from objects and equipment already present at ground level.

This type of decision seems simple once the result is visible, but it must be made before drilling, securing the supports, and preparing the connections.

The masonry wall also influences the work method

The outdoor unit is placed against a light brick facade. The choice of anchors and support structure must therefore be adapted to the building.

A central heat pump in this category represents a considerable mechanical load. It is not enough for the support to appear solid immediately after installation: it must remain stable during startup cycles, periods of wind, temperature changes, and years of use.

We also pay attention to vibrations. A poorly designed rigid installation can transmit more noise to the structure. The contact points between the unit and the support must therefore be properly prepared.

Another nearby unit: avoid creating a conflict between two systems

The photograph clearly shows a second condenser to the left of the new MIDEA.

Whether it is part of another system still in use or simply located in the work area, its presence changes how we can use the space.

Two outdoor units must not be positioned so that they blow their hot or cold air directly at each other. They must also remain accessible to technicians.

This is an aspect that is often overlooked when several pieces of equipment have been added successively around a house.

In Saint-Clet, the elevated positioning of the MIDEA EVOX G3 allows us to make better use of the available space without accumulating site constraints.

Horizontal discharge that requires maintaining clearance in front of the unit

The EVOX G3 uses a large front-mounted fan with horizontal discharge.

MIDEA indicates that the outdoor design combines a horizontal fan and a vertical heat exchanger to promote more uniform airflow across the entire heat exchanger. The indoor design of the range also uses a symmetrical fan and an M-Coil-type coil to improve air distribution.

The clearance in front of the unit is therefore very important.

We avoid installing a solid fence, shed, wall, or any other significant obstacle directly in front of the fan. A unit may have enough space to physically « fit » while still not having enough space to operate properly.

A heat pump designed to continue heating down to -30 °C

One of the main advantages of the MIDEA EVOX G3 Extreme Heat is its low-temperature performance.

The MIDEA brochure announces continuous heating operation down to -30 °C. In the tests presented for a three-ton MIDEA system, the manufacturer also indicates up to 100% of the rated heating capacity at approximately -25 °C, with a COP of approximately 1.9.

MIDEA also explains that its compressor technology uses vapor injection at an intermediate temperature when the system operates in extreme cold. This strategy increases the amount of compressed refrigerant to support heat production.

These figures explain why we place so much importance on the outdoor installation.

Selecting a heat pump that can operate at -30 °C while placing it too close to the ground, where it could quickly become surrounded by snow or ice, would make no sense.

EVOX G3 efficiency: up to 19 SEER2 and 10.8 HSPF2

The EVOX G3 family covers several capacities. MIDEA documentation indicates a range of approximately 18,000 to 54,000 BTU/h, with efficiencies of up to 19 SEER2, 12.5 EER2, 10.8 HSPF2, and a maximum advertised COP of 2.14 at 5 °F, or approximately -15 °C, depending on the equipment combination.

The third-generation technical table includes, among others, the following values:

These performance figures and the line's various indoor/outdoor models are listed in the MIDEA EVOX G3 technical data sheet.

The complete model number in the photograph from our Saint-Clet project is not legible enough to identify one of these capacities with certainty for that specific unit. We therefore prefer to present the documented specifications for the product line rather than invent a tonnage.

Why this tonnage detail matters

When a homeowner compares quotes, it can be tempting to consider all EVOX G3 systems essentially identical.

That is not the case.

A 30,000 BTU/h combination and a 48,000 BTU/h combination do not have the same airflow rates, electrical characteristics, dimensions, or exactly the same efficiencies.

The right choice depends on the building's heating load, not just its floor area.

Insulation, windows, airtightness, number of floors, orientation, air infiltration, and especially the capacity of the ductwork must be taken into account.

Inside, the EVOX G3 must be configured as a complete system, not as a simple condenser replacement

The air handler is just as important as the outdoor heat pump

In the photo, attention naturally goes to the large unit installed on the metal support.

Yet, with a central system, a significant part of the result takes place inside the home.

The heat pump must work with an air handler capable of distributing the correct amount of air through the existing ductwork. Poor airflow can create temperature differences between rooms, increase noise at the grilles, and limit the equipment's actual performance.

That is precisely why we do not consider a central system installation complete simply because the outdoor unit is operating.

Up to 1.2 in. of static pressure with Computational Constant Airflow 2.0

MIDEA uses its Computational Constant Airflow 2.0 technology with the EVOX G3.

The documentation demonstrates adaptability to different duct and filtration conditions, with examples where a reference airflow of 1,200 CFM is maintained despite static pressure increasing from 0.4 to 1.2 in. of water column.

The unit also allows up to 60 airflow adjustment levels. The manufacturer explains that the motor can adapt its power and speed based on the resistance created by the ducts, filter, or coil.

This is useful when replacing an older central system, but it does not mean that all deficiencies in the ductwork can be ignored.

A return that is too small or a highly restrictive duct remains an issue that we must diagnose.

Block N Lock: an indoor unit that can be configured in several ways

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

The brochure presents six possible configurations, including vertical, left- or right-horizontal configurations and some low-boy configurations when available height is limited.

In the basements of Saint-Clet, Vaudreuil-Soulanges, Montréal, Laval, Longueuil, the South Shore and the North Shore, this flexibility can genuinely facilitate a replacement.

Older installations are not always built to the ideal dimensions of a new appliance. We sometimes have to work around a beam, a water heater, an electrical panel, a staircase, and existing ductwork.

Dimensions designed to facilitate furnace replacement

MIDEA also indicates that several EVOX G3 indoor units have widths ranging from approximately 14.5 to 21.5 inches, comparable to the dimensions of many residential furnaces.

The documentation also mentions adapting the indoor unit to 115 V or 208/230 V, depending on the application.

This can reduce some work during a retrofit, but we must still verify the actual site conditions.

The plenum, return air, drainage, available electrical capacity, and service clearances must be compatible with the new system.

Auxiliary heating up to 25 kW

For periods when additional output is required, the platform can accommodate an auxiliary electric heating assembly of up to 25 kW, with a three-stage configuration. MIDEA indicates that the stages can be activated based on temperature changes to fine-tune energy consumption and comfort.

This setting must be configured intelligently.

If the electrical elements start unnecessarily early, consumption can increase considerably. If the auxiliary heating is insufficient for the home's actual load, comfort can become problematic during the coldest periods.

24 V, 485 communication, and wireless communication

The EVOX G3 also offers several control options.

The documentation mentions compatibility with 485 communication, 24 V third-party thermostats, as well as Sub-1 GHz wireless communication between certain MIDEA components.

This flexibility is particularly useful when a home has old thermostat wiring that is difficult to replace.

However, the choice of control affects the available functions. An installation using a conventional thermostat will not necessarily provide access to all the capabilities of a complete communicating system.

MERV 13 filtration and airflow management

The EVOX G3 can be paired with a filtration module compatible with 1-, 2-, or 4-inch MERV 13 filters. MIDEA indicates that these filters can capture more dust, pollen, particles, and dander while helping keep the evaporator cleaner.

However, we always check static pressure.

Simply adding a more restrictive filter without checking the system's capacity can reduce airflow. In central HVAC, filtration and ventilation must be considered together.

R-454B: a new generation of refrigerant visible even in the safety warnings

The safety labeling specific to this new generation of equipment can also be seen on the side panel of the unit photographed in Saint-Clet.

The brochure confirms that MIDEA uses R-454B in this range. This A2L refrigerant is listed with a global warming potential of 466.

For the homeowner, this difference is barely noticeable once installation is complete.

For our technicians, it requires procedures adapted to R-454B: connection methods, leak testing, circuit evacuation, commissioning, and appropriate tools.

SmartHome and system diagnostics

With the MIDEA communicating thermostat and the SmartHome app, the manufacturer specifically provides scheduling, energy consumption monitoring, comfort adjustment, diagnostics, and remote software update features.

These features can also help the homeowner better understand how an inverter heat pump operates.

Unlike an older strictly on-off system, an inverter can operate for long periods at low speed. This extended operation is often desirable because it reduces large temperature fluctuations.

LogisVert in 2026: assistance depends on the exact combination, not simply on the EVOX G3 name

For a heat pump installed on or after November 26, 2025, Hydro-Québec currently requires ENERGY STAR certification for the unit to be eligible for the LogisVert program.

When all requirements are met, the current residential financial assistance is $50 per 1,000 BTU/h of heating capacity at -8 °C for an ENERGY STAR heat pump, or $120 per 1,000 BTU/h at -8 °C when it is also ENERGY STAR – Cold Climate certified. The applicable amount depends on the installation date.

It is therefore necessary to know the exact combination of the indoor and outdoor models, as well as its recognized capacity at -8 °C.

Since the Saint-Clet system's complete model number is not legible with sufficient certainty in the photograph, we are not publishing a specific LogisVert amount for this installation.

This is the right way to present a grant: based on the equipment's actual reference, not on the commercial name displayed on the condenser.

What this Saint-Clet project shows particularly well

Our Saint-Clet photo is interesting because it does not hide the process.

The new unit is already installed at its final height while the connections are still being completed. Another outdoor unit is located on the left. In front of and beneath the new heat pump, the metal support leaves much more open floor space. On the right, the piping and conductors show the actual route between the building and the service compartment.

These are exactly the kinds of details that determine whether an installation will be easy or difficult to maintain a few years later.

At AirGreen, when we install a central heat pump in Saint-Clet, Montreal, Laval, Longueuil, on the North Shore or the South Shore, we are not simply looking for somewhere to place the condenser.

We analyze the home's surroundings, snow, defrost cycles, nearby equipment, service access, the ductwork network, and how the equipment will be used in the middle of winter.

The MIDEA EVOX G3 brings sophisticated technology to this project. Our role is to ensure that the installation around this technology is just as well thought out.