Installation of a MIDEA EVOX G3 Central Heat Pump in Châteauguay, on Montreal's South Shore
Take a tour of the installation
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.
A Strategic HVAC Installation to Maximize Year-Round Comfort in a Châteauguay Home
At AirGreen, every HVAC installation project is an opportunity to optimize a residence's comfort, energy performance, and durability. In Châteauguay, on the South Shore of Montreal, we recently completed the full installation of a MIDEA EVOX G3 central heat pump | 1.5 tons (18,000 BTU) in a brick-built single-family home, typical of the area.
This project presented several technical specificities, including the existing duct system configuration, mechanical space management, and performance optimization in a demanding Quebec climate. Here is a detailed overview of this installation, the challenges encountered, and the solutions we implemented.
Why the MIDEA EVOX G3 central heat pump was the right choice
Performance adapted to South Shore winters
The MIDEA EVOX G3 central heat pump is distinguished by its ability to maintain stable performance down to -30 °C, making it a perfectly suited choice for the climatic conditions of Châteauguay, Longueuil, and Montreal.
In this project, the client was looking for:
- A reliable primary heating system
- Significant reduction in energy costs
- Uniform comfort in all rooms
- A subsidy-eligible solution
The EVOX G3 met these requirements thanks to:
- Heating capacity: 18,000 BTU
- SEER2: 19.0 (excellent cooling efficiency)
- HSPF2: 10.1 (heating performance)
- R-454B refrigerant gas: more ecological
- ENERGY STAR® (Cold Climate) certification
LogisVert Subsidy: A Concrete Advantage
The client will benefit from a $1764 subsidy through the LogisVert program, making this installation even more financially advantageous.
Site Analysis and Installation Preparation
Exterior configuration: concrete foundation wall and brick cladding
The outdoor unit was installed on a concrete foundation wall, under a brick facade. This configuration required:
- Solid fastening with anti-vibration wall brackets
- Particular attention to alignment to ensure good drainage
- Clean aesthetic integration, without compromising the existing structure
We strategically positioned the unit to:
- Minimize perceived indoor noise
- Facilitate future maintenance
- Optimize airflow around the compressor
Management of refrigerant and electrical lines
In this project, the refrigerant lines (3/8 – 3/4) were carefully installed following a discreet path along the exterior wall. We used:
- Robust mechanical protections
- Optimized routing to reduce thermal losses
- High-quality insulation to prevent condensation
The 220V electrical supply was neatly connected with an accessible, standards-compliant disconnect box.
Challenges Encountered and AirGreen Solutions
1. Limited access and aesthetic constraints
The client wanted a discreet installation that wouldn't compromise the exterior appearance of the house. The challenge was to integrate the outdoor unit without disrupting the facade's aesthetics.
Solution:
- Precise positioning below the window line
- Use of compact wall brackets
- Perfect alignment of conduits and cables
2. Optimization of the existing central system
The existing duct system required complete validation:
- Static pressure verification
- Leak inspection
- Airflow adjustment
Result:
We were able to retain the duct network by perfectly adapting it to the new central heat pump, which reduced costs for the client while ensuring optimal performance.
3. Drainage Management and Durability
Inadequate drainage can lead to long-term problems.
Our approach:
- Installation of a reliable drainage system
- Full testing to prevent any water accumulation
- Verification of winter clearance (snow and ice)
AirGreen Installation Process: Precision and Rigor
Every central heat pump installation in Montreal, Laval, Longueuil, or on the South Shore follows a strict protocol:
Key steps:
- Complete initial inspection
- Precise system sizing
- Mechanical installation (indoor and outdoor)
- Secure electrical connection
- Vacuum pull (micron test)
- Pressure test
- Commissioning and calibration
- Final validation with the client
In this project, the vacuum pull confirmed perfect sealing, guaranteeing maximum system longevity.
Final Result: Comfort, Efficiency, and Peace of Mind
After the installation, the client immediately noticed:
- A stable and uniform temperature
- A notable reduction in noise compared to the old system
- Better energy consumption management
The MIDEA EVOX G3 also offers intelligent control via WiFi, allowing the client to manage their comfort remotely.
Practical advice for homeowners in Châteauguay and the surrounding areas
Choosing an appropriate central heat pump
Here are some essential elements to consider:
- Actual capacity (BTU) adapted to the house
- Heating performance at low temperatures
- Compatibility with existing ducts
- Eligibility for subsidies
Common mistakes to avoid
- Undersizing or oversizing the equipment
- Neglecting the condition of the ducts
- Choosing an installer without central HVAC expertise
- Ignoring the quality of the installation (more important than the machine itself)
Why Trust AirGreen for Your HVAC Installation
At AirGreen, we stand out for:
- In-depth expertise in central heat pumps
- Clean, durable, and compliant installations
- Total transparency in our recommendations
- Precise knowledge of the Montreal, Laval, Longueuil, North Shore, and South Shore markets
Every project is handled with rigor, no matter its complexity.
A High-Performance Central Solution for South Shore Homes
The MIDEA EVOX G3 central heat pump installed in Châteauguay represents an excellent balance between performance, energy efficiency, and financial accessibility.
For homeowners seeking a reliable solution to face Quebec winters while optimizing their year-round comfort, this type of installation is a particularly relevant option.
The unit on this job, in figures
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 big day, step by step
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 would it look like at your place?
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.
Four mistakes we do not make
Flip each card to see what we do instead.
Your own project, step by step
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.
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.
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).