Installation of a GREE Flexx Ultra R32 central heat pump in Rosemont–La Petite-Patrie
AirGreen installed a GREE Flexx Ultra R32 central heat pump in Rosemont–La Petite-Patrie. It's an energy-efficient, reliable HVAC solution perfectly suited to Montreal buildings.
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A high-performance HVAC solution adapted to flat roofs in the heart of Montreal
At AirGreen , we recently installed a GREE Flexx Ultra R32 central heat pump on the flat roof of a residential building located in the Rosemont–La Petite-Patrie neighborhood, in the heart of Montreal. This project perfectly illustrates our expertise in adapting modern HVAC systems to the typical urban architectural constraints of Montreal, where flat roofs and restricted access require meticulous planning.
Context of the installation: a typical Montreal building
The building in question, a multi-unit apartment complex, required a reliable and efficient centralized heating and cooling solution to replace an aging system. The flat roof provided the ideal location for the condenser, while limiting noise pollution for occupants.
Our technicians chose the GREE Flexx Ultra R32 , a high-performance central heat pump, equipped with R-32 refrigerant, recognized for its energy efficiency and low environmental impact.
Choosing GREE Flexx Ultra R32: performance and durability
This central heat pump is designed to withstand Quebec winters, offering stable performance down to -25°C . It is distinguished by:
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Its superior energy efficiency , with a high SEER and an HSPF coefficient optimized for extended heating.
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Its compatibility with existing duct systems , which facilitates replacements without major work.
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Its inverter technology ensures constant comfort and a significant reduction in energy costs.
Technical details of the installation
The installation, carried out on a flat roof covered with gravel , involved several logistical challenges that our team met with precision:
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Galvanized steel supports fixed on treated wooden soles , ensuring perfect stability of the condenser.
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Complete insulation of refrigerant lines with high density sleeves to withstand extreme thermal variations.
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Neat routing of electrical and refrigerant conduits , concealed in waterproof white wiring for optimal protection and a clean aesthetic.
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Connection to the electrical panel made via a dedicated circuit breaker ensuring safety and compliance with Quebec standards.
This approach not only guarantees the reliability of the system, but also its longevity in the face of Montreal's variable climatic conditions .
Adapting to urban conditions: performance and discretion
Installing a high-performance HVAC system in a dense environment like Rosemont–La Petite-Patrie requires special attention to sound discretion and space optimization . Thanks to the compact design of the GREE Flexx Ultra R32 , we were able to maintain a regulatory distance from the peripheral walls while ensuring free and efficient airflow.
Safety, compliance and sustainability
All elements of the installation comply with the standards of the Quebec Building Code . Our technicians have verified:
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The inclination and solidity of the support to prevent any vibration.
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Gravity drainage of condensate, eliminating the need for a lift pump.
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Optimal compressor operation after pressurization and nitrogen leak testing.
Customer Benefits
With this new GREE Flexx Ultra R32 heat pump, the customer now benefits from:
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Consistent comfort all year round — heating in winter, air conditioning in summer.
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Reduced energy consumption , supported by R-32 technology.
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Potential access to Quebec subsidies for energy efficiency.
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Simplified maintenance thanks to a centralized and accessible system.
An installation emblematic of AirGreen know-how
This installation illustrates AirGreen 's ability to combine technical expertise , quality of execution , and respect for Montreal's architectural particularities . Each project is custom-designed to ensure the best possible energy performance and comfort for our clients.
The job tools
Two quick checks with real numbers: what heat costs, and what your current heaters add up to in BTU/h.
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).