Installation of a MIDEA EVOX G3 central heat pump in Havelock, in Haut-Saint-Laurent, Montérégie
In Havelock, AirGreen installs a MIDEA EVOX G3 central heat pump on an elevated support: heating down to -30 °C, inverter technology, R-454B, airflow management, and installation adapted to Quebec winters.
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The job on one screen
The unit’s data sheet
The range as published on airgreen.ca: pick a size to see its capacity in deep cold.
| Size | Heating at −8 °C | Heating at −15 °C | Coldest certified point | COP at −15 °C | SEER | HSPF | Indicative LogisVert aid |
|---|---|---|---|---|---|---|---|
| Midea EVOX G3 · 1.5 tons | 14,700 | 18,600 | −30 °C: 11,800 | 2.12 | 19.0 | 10.1 | $1,764 |
| Midea EVOX G3 · 2 tons | 20,800 | 20,600 | −30 °C: 12,100 | 2.14 | 18.6 | 10.0 | $2,496 |
| Midea EVOX G3 · 2.5 tons | 24,000 | 33,200 | −30 °C: 17,900 | 1.97 | 17.2 | 10.8 | $2,880 |
| Midea EVOX G3 · 3 tons | 33,000 | 37,400 | −30 °C: 27,600 | 1.9 | 18.0 | 10.0 | $3,960 |
| Midea EVOX G3 · 4 tons | 39,500 | 48,000 | −30 °C: 27,200 | 2.0 | 17.5 | 9.5 | $4,740 |
| Midea EVOX G3 · 5 tons | 45,000 | 54,000 | −30 °C: 37,300 | 1.9 | 17.5 | 9.5 | $5,400 |
Data read live from the airgreen.ca page of each size (NEEP / AHRI certified performance). When the title names the installed size, it is highlighted; otherwise the whole range is shown. The aid shown is today’s, using Hydro-Québec’s rule ($120 per 1,000 BTU/h at −8 °C); amounts quoted in the article date from its publication. Only Hydro-Québec confirms the assistance granted.
The article, chapter by chapter
An EVOX G3 installed high against the foundation: a project where Havelock's climate directly influences the installation method
In Havelock, in the Haut-Saint-Laurent RCM in Montérégie, we installed a MIDEA EVOX G3 central heat pump in a residential setting where the outdoor placement had to be carefully planned. Havelock is officially a township municipality in Montérégie, within the Haut-Saint-Laurent RCM.
The photo of this AirGreen installation already tells much of the story. The dark gray outdoor unit of the MIDEA EVOX G3 is installed in front of a residential concrete foundation topped with a brick wall. Rather than placing the unit near the ground, we chose an installation on an elevated metal support secured to the foundation. This keeps the large front fan completely clear for air discharge.
Several existing elements had to coexist with the new installation: a metal railing on the left, two wall vents on the right, a vertical element along the wall, and the electrical disconnect installed near the unit. The refrigerant lines connect directly to the side of the condenser, with a relatively short outdoor route.
This is exactly the kind of project that shows that a central heat pump installation is not simply a matter of choosing a capacity in BTUs and connecting two units. The height of the outdoor unit, its orientation, airflow, service access, defrost cycles, the indoor duct network, and the system settings must all work together.
Why raise a central heat pump so high in Havelock
This choice is particularly appropriate in a region like Haut-Saint-Laurent, where a heat pump must continue operating through genuine Quebec winter conditions.
In heating mode, the outdoor coil can accumulate frost. The system then automatically performs defrost cycles. The water produced must be able to drain beneath the unit without gradually forming a block of ice against its base.
Installing the condenser higher also helps protect it from snow accumulating around the foundation.
In the photo, the advantage is clear: the lower part of the EVOX G3 remains well clear of the ground. The open space facilitates drainage, seasonal maintenance, and snow removal around the equipment.
A height that must remain functional year-round
For a central heat pump, we specifically aim to avoid:
- that snow would quickly reach the bottom of the heat exchanger;
- that ice would trap the base of the machine;
- that vegetation would gradually touch the condenser;
- that leaves or debris would accumulate directly against the unit;
- that a technician would have to work in an unusable space during future maintenance.
However, significant elevation does not mean that winter maintenance becomes unnecessary. Even when properly installed, a heat pump in Havelock must remain free of snow around its air intakes and outlets.
An unobstructed front-facing fan rather than one enclosed between two obstacles
The MIDEA EVOX G3 shown in the photograph uses a large horizontal-discharge fan.
Midea specifically describes the EVOX G3’s outdoor design as a combination of a horizontal-discharge fan and a vertical heat exchanger. According to the manufacturer, this geometry is intended to provide more uniform airflow across the heat exchanger and promote performance as the outdoor temperature drops.
On this job site, the condenser’s front faces directly toward an open area. Therefore, there is no solid fence or other wall immediately in front of the fan that would trap the discharged air.
This detail deserves more attention than one might think.
When a condenser discharges its air into a space that is too confined, some of that air can return toward the heat exchanger. This recirculation can degrade the heat pump’s operating conditions. That is why we always consider the clearances specified by the manufacturer before deciding on the final position.
The foundation vents visible to the right of the unit also had to remain functional
Two outlets or vents are visible in the brick to the right of the outdoor unit. On a real job site, equipment already present on a facade does not simply disappear because a heat pump needs to be installed.
We must preserve the building’s functions and avoid creating a new obstruction.
This photo is a good example of what “finding the right place” really means: a relatively large machine must be accommodated while respecting openings, access points, and the home's other components.
The electrical disconnect remains easily accessible
The disconnect box is located at the bottom right of the machine.
Its location is not merely decorative. It allows the equipment to be isolated during maintenance or diagnostics. We therefore want it to remain accessible after installation and not be hidden behind landscaping that would complicate servicing.
With a central HVAC installation, the quality of the result also depends on these details: electrical power supply, protection devices, wiring routes, refrigerant piping, anchoring, clearances, and technical access.
A heat pump designed to operate well below 0 °C
The major technical advantage of the MIDEA EVOX G3 Extreme Heat lies in its cold-weather heating capabilities.
The Midea documentation attached to this project indicates continuous operation down to -30 °C. It also states that, for the Extreme Heat platform, the capacity can reach 100% of the rated heating capacity at approximately -25 °C, with a COP of up to 1.9 under the conditions presented by the manufacturer. Some of the brochure's performance data are based on a 3-ton Midea system; they should therefore not automatically be attributed to every capacity in the range.
This distinction is important at AirGreen.
We do not take performance achieved by one combination and present it as if it automatically applied to every EVOX G3. The outdoor unit, air handler, capacity, and certified combination must be verified.
M-Powevi technology behind cold-weather performance
Midea uses its M-Powevi compressor technology to support performance as temperatures drop significantly.
The brochure states that, under extreme cold conditions, the system injects vapor at an intermediate temperature to increase the total amount of compressed refrigerant and maintain greater heating capacity.
For a homeowner, the benefit is very practical: a heat pump intended for the Quebec climate must be evaluated based on what it can deliver in January and February, not solely on its cooling performance during the summer.
A range of EVOX G3 capacities
The photo does not show enough of the nameplate to identify with certainty the exact BTU capacity of the unit installed in Havelock. We therefore do not want to assign a tonnage to this installation based solely on the apparent dimensions of the condenser.
However, Midea's technical brochure presents several EVOX G3 Extreme Heat configurations:
| Nominal cooling capacity | Published nominal heating capacity | SEER2 | EER2 | HSPF2 | Heating at -15 °C |
|---|---|---|---|---|---|
| 18,000 BTU/h | 18,000 BTU/h | 19,0 | 12,5 | 10,1 | 18,600 BTU/h |
| 24,000 BTU/h | 24,000 BTU/h | 18,6 | 12,0 | 10,0 | 20,600 BTU/h |
| 30,000 BTU/h | 33,000 BTU/h | 17,2 | 12,0 | 10,8 | 33,200 BTU/h |
| 36,000 BTU/h | 36,000 BTU/h | 17,7 | 12,0 | 10,0 | 32,600 BTU/h |
| 48,000 BTU/h | 48,000 BTU/h | 17,5 | 12,0 | 9,5 | 48,000 BTU/h |
| 54,000 BTU/h | 55,000 BTU/h | 17,5 | 12,0 | 9,5 | 54,000 BTU/h |
These performance figures appear in the technical table for the EVOX G3 Extreme Heat generation.
The key point for a homeowner is therefore this: MIDEA EVOX G3 is a family of central heat pumps, not a single unit with a fixed capacity.
Proper sizing depends on the home's heat losses, envelope, floor area, number of floors, windows, duct network, and several other factors.
Why an inverter system is beneficial in a home equipped with ducts
An inverter central heat pump is not designed to operate continuously according to a strictly "on or off" logic.
The system can adjust its output to the building's demand. When a home requires less heating or cooling, the equipment can reduce its capacity rather than systematically operating at full power.
This modulation can help achieve:
more stable temperatures, longer and more consistent operating cycles, better energy consumption management, and operation better adapted to variations in the heating load.
But once again, the result depends on the complete installation. An excellent compressor cannot by itself correct a severely undersized ventilation network.
Behind Havelock's condenser: the invisible central work that really determines comfort in the home
A central heat pump is only as good as the duct network to which it is connected
The outdoor photo naturally draws attention to the large Midea condenser. Yet a significant part of our work takes place indoors.
Unlike a wall-mounted heat pump, the central heat pump distributes its air through the home's duct network. Available airflow, static pressure, air returns, filtration, and balancing therefore become essential.
A home can have a high-performance heat pump and still experience:
- a room that remains too cold;
- a floor that receives too little air;
- noisy dampers;
- excessive pressure in the ducts;
- insufficient airflow through the coil.
That is why we never consider equipment replacement to be a simple box swap.
Computational Constant Airflow 2.0: up to 1.2 in. of static pressure under the specified conditions
The EVOX G3 offers a particularly interesting feature for renovations: Computational Constant Airflow 2.0.
Midea indicates that the system can adjust fan power to the conditions of the duct system and presents a working capacity of up to 1.2 in. of water column static pressure in the applications described in the documentation.
The platform also allows up to 60 air volume adjustment levels, enabling finer adjustment of the fan's behavior.
This gives our technicians greater latitude during commissioning.
However, this does not mean that an undersized duct or a completely clogged filter becomes acceptable. The proper method remains to identify the cause of a restriction before relying on the motor to compensate for it.
A useful modular indoor unit for Quebec basements
Mechanical rooms are not always spacious. We regularly encounter, in Montreal, Laval, Longueuil, the North Shore, the South Shore and Montérégie, furnaces installed under beams, between plumbing lines, or in spaces where a few centimeters completely change the work method.
The EVOX G3 air handler uses a modular architecture that Midea presents for several orientations: upflow, downflow, right horizontal, left horizontal, and “low-boy” configurations when available height is limited.
Midea also indicates that certain EVOX G3 units have widths comparable to those of residential furnaces, ranging from approximately 14.5 to 21.5 inches depending on capacity.
In a replacement project, this feature can limit the modifications required around the indoor unit.
Auxiliary heating: up to 25 kW available depending on the configuration
Even with a heat pump capable of operating at very low temperatures, a Quebec central system must be designed with auxiliary heating in mind.
The EVOX G3 brochure specifies three-stage auxiliary heating assemblies capable of reaching 25 kW, with modulation based on settings and demand.
The goal is not to run the electric components unnecessarily. Instead, the settings should allow the heat pump to handle as much of the load as possible while retaining the auxiliary capacity needed when building conditions require it.
Incorrect settings can reduce some of the savings sought, even with an excellent system.
Communicating thermostat or 24 V control
Another useful advantage in renovations is control flexibility.
Midea indicates that the EVOX can operate with 485 communication or at 24 V, with control mode detection. Some configurations therefore support a third-party 24 V thermostat, while the complete Midea ecosystem can use its communicating controller.
The platform also supports integration with the SmartHome app, including scheduling, certain comfort controls, consumption monitoring, and diagnostic functions.
For a renovation where existing wiring runs through multiple floors or finished walls, this flexibility can make a significant difference.
MERV 13 filtration and airflow: both must be considered together
The EVOX G3 documentation provides for filtration compatible with 1 in., 2 in., and 4 in. filters, including MERV 13 options.
A MERV 13 filter can capture more fine particles, dust, pollen, and pet hair than a very basic filter.
But we never recommend choosing a filter solely because its MERV rating is higher.
The filter must also be properly sized for the required airflow. A filter that is too restrictive in a holder that is too small can unnecessarily increase static pressure.
An R-454B generation
The EVOX G3 is also part of the new generation of equipment using R-454B refrigerant.
Midea indicates that this A2L refrigerant has a global warming potential, or GWP, of 466. The EVOX central lineup is among the equipment affected by this transition.
This refrigerant change also means changes to installation practices. A2L equipment must be installed and serviced using the appropriate procedures, tools, and precautions.
LogisVert: eligibility must be verified for the exact combination
For a Havelock homeowner comparing the cost of a MIDEA central heat pump, the Hydro-Québec rebate can obviously factor into the decision.
In September 2026, the LogisVert program provides, when all conditions are met, assistance of $50 per 1,000 BTU/h at -8 °C for an ENERGY STAR-certified heat pump and $120 per 1,000 BTU/h at -8 °C for an ENERGY STAR cold-climate heat pump.
The subsidy must not be calculated simply by multiplying the unit’s nominal tonnage by $120.
Hydro-Québec uses the recognized capacity at -8 °C of the eligible combination. The outdoor unit, indoor unit, and combination certification must therefore be verified before announcing a final amount.
This is an important difference between a rough estimate and a properly prepared quote.
What we check before commissioning an EVOX G3
On a central installation such as the one in Havelock, our work does not stop when the condenser is mounted on the wall.
Commissioning includes checking the refrigerant and electrical connections, drainage, control settings, indoor-unit operation, and airflow through the ductwork.
We pay particular attention to CFM because a significant difference in airflow can affect supply-air temperatures, noise levels, and the system’s overall operation.
The brochure also shows that EVOX G3 air handlers cover a wide range of airflow rates depending on capacity, from approximately 618 CFM on some smaller configurations to more than 1,800 CFM on the largest ones.
The final adjustment must be tailored to the home rather than chosen solely based on a generic value.
Three visible details on this installation that will still make a difference several years later
First, the height. The condenser is sufficiently elevated above the ground to better handle snow and defrost water.
Second, access. The front and the technical side of the unit remain accessible. The disconnect can be reached without dismantling any landscaping.
Third, the routing of the connections. The lines leave the building near the unit, limiting the amount of visible outdoor piping.
These are not the features that attract the most attention in a brochure. Yet they are exactly the details that can simplify HVAC maintenance and help keep an installation clean over the years.
Mistakes to avoid when replacing a central heat pump
An installation like this highlights several points that we systematically monitor at AirGreen:
- Do not choose the capacity based solely on the size of the house. Actual heat losses matter more.
- Do not install the condenser too close to the ground in an area exposed to snow.
- Do not overlook the airflow and static pressure of the existing ductwork.
- Do not install a more restrictive filter without checking its impact on airflow.
- Do not block service panels, the disconnect switch, or building openings.
- Do not advertise a LogisVert rebate without confirming the eligible combination.
- Do not treat auxiliary heating as a simple accessory without configuring it.
This rigor applies equally to an HVAC installation in Havelock and to our central heat pump projects in Montreal, Laval, Longueuil, on the North Shore, and on the South Shore.
An outdoor installation that appears simple, but is built around winter operation
The installation photographed in Havelock is visually understated: a gray unit against a brick façade, a metal support, a few connections, and a disconnect switch.
But behind this apparent simplicity are the decisions that determine the true quality of an installation: location, height, capacity, airflow, central system, controls, filtration, auxiliary heating, and commissioning.
This is also what makes the MIDEA EVOX G3 interesting for a central system conversion or modernization project. The range combines inverter technology, operation rated down to -30 °C, multiple capacities, a modular indoor unit, advanced airflow control, and compatibility suited to different renovation scenarios.
At AirGreen, our role is to ensure that these technical features are genuinely put to use in the home.
A heat pump that performs well on paper is not enough. It must be installed in the right location, sized for the building, connected to a system capable of distributing its air, and configured to operate efficiently during Quebec winters.
This MIDEA EVOX G3 central heat pump installation in Havelock is a concrete example: an elevated outdoor unit that is accessible and properly integrated into an existing façade, with a design that takes snow, defrosting, servicing, and long-term operation into account from day one.
The job tools
Two quick checks with real numbers: what heat costs, and what your current heaters add up to in BTU/h.
Baseboards and electric furnaces turn 1 kWh of electricity into 1 kWh of heat. A heat pump delivers more: that is its COP. At Hydro-Québec’s rate D (11.142¢/kWh above 40 kWh a day, since 1 April 2026):
Hydro-Québec: a heat pump can be up to three times more efficient than baseboards for heating in the colder months.
Estimate per kWh of heat, at the chosen temperature, using the certified COP from the product page. Taxes, access charge and backup heat not included.
Conversion: 1 W = 3.412 BTU/h. An indication, not a load calculation: baseboards and furnaces are often stronger than the real need, and they can stay as backup. AirGreen confirms the capacity on site.
How the job unfolds
The main steps of this kind of job at AirGreen. Every house has its quirks: the estimate brings them out.
We look at the ducts, the current indoor module, the electrical panel and the planned spot for the outdoor unit.
The equipment combination, capacity and price, in writing. We check whether the combination qualifies for assistance programs.
Access protected, old unit disconnected and removed when it is being replaced.
Electric furnace or air handler, with its coil, connected to the supply and return ducts.
On a level base, raised above the snow, with free space all around.
Insulated, they enter through a sealed opening and run to the indoor coil.
Dedicated circuits, accessible disconnect, a thermostat that works with the heat pump and the backup heat.
Leak test, vacuum, start-up, airflow check and a test of both modes.
Filter, thermostat, backup heat in extreme cold: what to know before winter.
- The on-site estimateWe look at the ducts, the current indoor module, the electrical panel and the planned spot for the outdoor unit.
- The quoteThe equipment combination, capacity and price, in writing. We check whether the combination qualifies for assistance programs.
- Getting readyAccess protected, old unit disconnected and removed when it is being replaced.
- The indoor moduleElectric furnace or air handler, with its coil, connected to the supply and return ducts.
- The outdoor unitOn a level base, raised above the snow, with free space all around.
- The refrigerant linesInsulated, they enter through a sealed opening and run to the indoor coil.
- Electrical and thermostatDedicated circuits, accessible disconnect, a thermostat that works with the heat pump and the backup heat.
- Tests and start-upLeak test, vacuum, start-up, airflow check and a test of both modes.
- The walkthroughFilter, thermostat, backup heat in extreme cold: what to know before winter.
What we check on a job like this one
Each number is a point we check on site. Switch between summer and winter to watch air and heat move.
In summer, the outdoor unit rejects the house's heat outside.
Generic illustration of this type of installation, not a survey of this job site. Tap a number.
It captures or rejects heat outside. It sits on a level base, above the snow, with free space all around.
The insulated refrigerant lines enter the house through a sealed opening and run to the indoor coil.
A shut-off switch near the outdoor unit isolates it safely for service.
Sitting on the indoor module, it moves heat between the house air and the refrigerant.
Electric furnace or air handler: its fan pushes air through the ducts. The electric backup takes over in extreme cold.
Supply ducts bring air to the rooms; returns bring it back to the unit. Their condition matters as much as the unit's.
It protects the coil and the fan. A dirty filter cuts airflow, so it gets checked regularly.
It runs the heat pump and the backup heat. It must be compatible with the installed system.
Is your home ready?
Check what applies at your place. A "no" is not a refusal: it is what we sort out during the estimate.
Good habits, once the unit is in place
Six simple habits that keep the unit going. Your list stays on this device.
What to do, season by season
Three habits per season for this unit. They take a few minutes and prevent many calls.
- Check the indoor module's filter.
- Clear winter debris from the outdoor unit.
- Test cooling before the heat arrives.
- Check the filter more often in peak season.
- Keep registers and returns clear.
- Watch condensate drainage near the coil.
- Change or clean the filter.
- Test heating and backup heat before the cold.
- Book periodic maintenance.
- Clear snow around the outdoor unit.
- Store nothing in front of the indoor module.
- Note any unusual noise or smell and call us.
The right pages, at the right time
Four statements: true or false?
It all comes down to details you have just seen.
1. A central heat pump uses the house's ducts.
It connects to the existing ducts to heat and cool everywhere.
2. In extreme cold, electric backup heat can take over.
The indoor module (furnace or air handler) works with the heat pump and takes over in extreme cold.
3. The filter only gets changed when the unit breaks down.
A dirty filter cuts airflow. It gets checked regularly.
4. You can reuse the old unit's size without checking.
The house may have changed: insulation, windows, added rooms. Capacity is confirmed on site.
0 / 4 right answers
What people ask us about this kind of work
Can I keep my current ducts?
What happens in extreme cold?
Furnace, air handler, ducted: what is the difference?
Are there grants?
Do I need a permit?
How much can I save?
How is the LogisVert assistance calculated?
Will my current thermostat work?
Central or wall units: which one?
Does AirGreen hold the required licences?
Is the estimate free?
No question matches. Write to us: we answer.
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Text and photo: a real AirGreen Climatisation & Chauffage job. The diagrams are generic illustrations of the type of installation, not a survey of this job site. Sources of the added figures: airgreen.ca product pages (NEEP / AHRI performance), Hydro-Québec (Heat pumps page, LogisVert, read on 13 October 2026), Régie de l’énergie (rate D as of 1 April 2026).