A multi-zone installation designed for a narrow courtyard, with a clean finish and preserved technical access
In the Plateau-Mont-Royal borough, installing a three-head heat pump often requires more preparation than a project carried out on an open lot. The brick walls are close together, passageways are narrow, wooden decks occupy a large part of the courtyard, and every outdoor component must coexist with doors, light fixtures, downspouts, and service conduits.
This AirGreen project precisely illustrates this type of situation: a GREE FREEMATCH R32 outdoor unit installed in a brick alcove, on a raised metal structure, with carefully routed vertical refrigerant lines and accessible electrical power.
Choosing a multi-zone system makes it possible here to power three indoor units from a single outdoor unit. For a multi-room dwelling, an urban cottage, or a Plateau-Mont-Royal plex, this configuration avoids multiplying outdoor units on the façade or in the courtyard. It also provides zone-by-zone control: each indoor head can receive a setting suited to the room it serves, while sharing the capacity of the same outdoor compressor.
An outdoor space where every centimeter had to be used intelligently
The installation photo shows a typically Montreal environment: two closely spaced brick walls, a wooden floor, a nearby door, and limited space available for positioning the equipment.
We installed the outdoor unit on a raised metal bracket, rather than placing it directly on the deck. This decision offers several concrete advantages:
- it limits direct contact between the machine’s base and moisture that may remain on the wood;
- it makes inspection underneath the appliance easier;
- it improves installation stability;
- it helps keep the heat pump above small accumulations of water, leaves, and debris;
- it provides clearer access to the connections located on the side of the unit.
The fan’s orientation also matters. In a narrow courtyard, the air discharged by the outdoor unit must circulate without being immediately pushed back toward the heat exchanger. Poor orientation can reduce efficiency, increase defrost cycles, and amplify perceived noise.
In this installation, the fan face remains directed toward the open part of the terrace, while the service panel remains accessible. The unit does not obstruct the neighboring door, and the space required for future HVAC maintenance has been preserved.
The outdoor electrical disconnect, visible on the brick wall, is placed near the unit. The cables are routed neatly, without unnecessarily crossing the traffic area. The refrigerant lines run up through a large vertical line-set cover in a light color, which blends better with the masonry and the building’s finish.
In a borough where the appearance of façades, balconies, and courtyards is often important, this type of finish makes a real difference. A good installation must be technically compliant, but it must also respect the building’s architecture.
Why a three-head heat pump is well suited to this type of home
A multi-zone heat pump becomes particularly appealing when needs vary from room to room. In Le Plateau-Mont-Royal, we frequently encounter deep apartments, front and rear rooms with different sun exposure, as well as floors whose temperature does not match that of the ground floor.
For example, three indoor units can serve:
- the main open-plan area;
- a bedroom or office at the front;
- a rear room or a floor that is more difficult to heat or cool.
This distribution reduces temperature differences and prevents a single wall-mounted unit from having to push air through hallways, doors, and stairwells. It also makes it possible to lower the setpoint in a seldom-used room, rather than conditioning the entire home uniformly.
However, one important limitation must be understood: a conventional residential multi-zone system such as the GREE FREEMATCH R32 is not a heat recovery system. The indoor units can receive different setpoints, but they normally operate in the same general mode, either heating or cooling.
This characteristic must be explained before installation, especially in buildings where a very sunny room may require cooling while another zone requires heating.
Performance suited to Montréal’s temperature fluctuations
The first page of the series’ technical data sheet states that it can achieve up to 21 SEER2, 12.5 EER2, and 10 HSPF2. It specifies an operating range in cooling mode of -30 °C to 48 °C and in heating mode of -30 °C to 24 °C, as well as a total piping length of up to 100 meters, depending on the outdoor unit selected.
SEER2 expresses seasonal cooling efficiency, while HSPF2 concerns seasonal heating efficiency. These indices make it possible to compare units under standardized conditions. Actual consumption nevertheless depends on several factors: desired temperature, building insulation, usage habits, head placement, filter cleanliness, and installation quality.
Published efficiency therefore does not replace precise sizing. An oversized system can lead to short cycles, less stable dehumidification, and greater temperature fluctuations. An undersized system may run continuously during cold snaps without reaching the desired setpoint.
The photo confirms that this is a GREE unit, but it does not allow us to read the outdoor unit's complete model number with certainty. We therefore avoid assigning an unverified capacity to this project.
The table on page 2 lists outdoor units from 18,000 to 42,000 BTU/h. The 24,000 BTU/h model accepts two to three indoor units, while the 30,000, 36,000, and 42,000 BTU/h models allow more numerous configurations.
For a three-head installation, several outdoor unit combinations may therefore be possible. The final choice must be confirmed based on:
- the heat load of each room;
- the area and volume of the zones;
- insulation level;
- window area;
- sun exposure;
- design temperatures;
- the available capacity when several heads operate simultaneously.
Mechanically adding the BTUs listed on the three indoor units is not a reliable sizing method.
The role of R32 refrigerant and G10 Inverter technology
The R32 belongs to the A2L class, a category of low-flammability refrigerants. Its use requires compatible tools, precisely executed connections, rigorous leak testing, and commissioning in accordance with the manufacturer's methods.
The FREEMATCH R32 product sheet specifically mentions an included A2L leak detection sensor, intelligent defrosting, self-diagnostics, automatic voltage adaptation, quiet operation, and G10 Inverter technology. It also states that the series can be combined with several indoor unit options.
Inverter modulation allows the compressor to adjust its speed to actual demand instead of operating only at full capacity and then stopping. In a three-head system, this modulation is essential: demand can change quickly when just one zone is operating and then when two or three rooms simultaneously call for heating or cooling.
Proper modulation helps stabilize temperatures, limit repeated starts, and reduce consumption when demand is low. However, it cannot compensate for incorrect sizing or a deficient installation.
The technical steps that protect long-term performance
For this type of HVAC installation, quality is not limited to mounting the heads and connecting the pipes. Our method includes several critical checks.
1. Load calculation and distribution across the three zones
We assess the floor area, ceiling height, windows, insulation, building orientation, and use of each room.
The heads should be positioned to promote natural air circulation. A unit installed directly above a large cabinet, facing a nearby partition, or in an enclosed corner may have sufficient capacity on paper without properly distributing air throughout the room.
We also consider the capacity of the outdoor unit when all three heads are operating at the same time. The nominal capacity of each indoor unit does not necessarily correspond to the capacity it will receive during simultaneous demand.
2. Validation of the route for the connections and drains
Before drilling, we plan the routing of the copper pipes, communication cables, and condensate drains.
In a brick building, penetrations must be carefully positioned, properly sealed, and arranged to avoid a visible network of conduits running in several directions. The vertical pipe cover in this project groups the services into a clean, coherent layout.
Each indoor unit must also drain its condensate reliably. When a natural slope is not possible, a pump may be required. The choice between gravity drainage and a pump must be made before closing the covers, not after a water leak appears.
3. Stable installation of the outdoor unit
The support must withstand the weight of the machine, vibrations, and freeze-thaw cycles. On a wooden deck, we check the structure’s strength and load distribution.
Anti-vibration elements may be added when vibration transmission to the building could be noticeable. The positioning must also leave enough space to remove the panels, inspect the valves, and carry out future cleaning.
4. Leak-tightness testing and vacuum pump-down
The refrigerant connections must be checked before releasing the refrigerant contained in the outdoor unit.
A nitrogen pressure test and a measured vacuum pump-down help limit the risk of moisture, residual air, and leaks in the circuit. This step directly affects compressor life, performance stability, and system reliability.
A connection that appears properly tightened to the naked eye may still have a slow leak. That is why instrumented checks are an integral part of a professional installation.
5. Commissioning the three heads
We check the communication between each indoor unit and the outdoor unit, supply-air temperatures, drains, error codes, vibrations, clearances, and operation in the available modes.
The customer also receives explanations about:
- the logic of multi-zone operation;
- using the remote controls;
- cleaning the filters;
- the difference between automatic mode and heating or cooling modes;
- the settings to prioritize to prevent the units from sending contradictory commands;
- the importance of keeping the outdoor unit free of snow, leaves, and ice.
What Plateau homeowners should check before choosing a three-head GREE FREEMATCH R32
The exact capacity must be calculated, not estimated based on the number of rooms
Three heads do not automatically mean that you need to select the largest outdoor unit. A well-insulated bedroom may require little capacity, while an open-plan area with large windows may account for most of the building's load.
We therefore calculate the contribution of each zone and verify the combinations authorized by the manufacturer.
This analysis prevents two common errors: installing an oversized outdoor unit solely to add up the BTUs listed on the indoor units, or choosing a unit that is too small on the assumption that the three heads will never operate simultaneously.
The electrical panel must be checked before ordering
The outdoor units in the series operate at 208/230 V. Depending on capacity, the specifications indicate a minimum circuit ampacity and maximum overcurrent protection that vary from one model to another. For units that can power three heads, the specified maximum protection ranges from 25 to 45 A.
In a plex or an older apartment in Le Plateau-Mont-Royal, this inspection may reveal a panel that is already heavily loaded, insufficient space for a two-pole circuit breaker, or more complex electrical routing than expected.
The analysis must be carried out before installation to avoid a last-minute modification, a model change, or electrical work not included in the initial quotation.
Defrost water must be managed on a wood terrace
In heating mode, a heat pump produces water during its defrost cycles. On a terrace, this water can create a slippery area, freeze beneath the unit, or accumulate near the structure.
The raised support visible in this project reduces direct contact with the floor, but a safe drainage path must still be provided, and the area beneath the unit must be kept free of snow and ice.
You should also avoid installing the outdoor unit where roof water can fall directly onto the heat exchanger. Ice from a gutter or roof overhang can block the fan, damage the machine, or interfere with defrosting.
Lengths and height differences influence the choice of model
The series does not have the same limits for every capacity. The technical table on page 2 indicates maximum total lengths ranging from 40 to 100 meters and maximum height differences of 15 to 25 meters, depending on the outdoor unit. It also specifies 1/4-inch liquid lines and 3/8-inch gas lines for the units shown.
This information becomes important when one head is located upstairs, another is at the back of the building, and a third must serve a remote room.
A route that appears short on a plan may exceed the limits once the risers, detours, distances between the units, and concealed sections are actually measured. An additional length may also require an adjustment to the refrigerant charge according to the manufacturer's guidelines.
Noise should be evaluated based on the yard, not just the specification sheet
The product range table indicates an outdoor sound pressure level of 54 to 63 dB(A) at high speed, depending on capacity.
In a yard surrounded by brick walls, surfaces can reflect sound. The location, fan orientation, supports, and distance from windows are therefore just as important as the published rating.
In this project, the outdoor unit is oriented toward open space rather than directly toward a nearby wall. This arrangement promotes air discharge and reduces the risk of sound being concentrated in an enclosed corner.
You should also avoid placing the unit beneath a bedroom window when other compliant locations are available. Even a relatively quiet heat pump can become noticeable when the yard acts as a resonance chamber.
Clearances should never be sacrificed to gain a few centimeters
A compact installation does not mean that the unit can be wedged between two obstacles. The prescribed clearances ensure air intake, air discharge, access to connections, and panel removal.
Among the mistakes to avoid are:
- place the fan facing a wall that is too close;
- block the service panel with a guardrail or permanent structure;
- place the unit directly on an unstable surface;
- route the lines through an area where they could be crushed;
- installing the outdoor unit beneath falling ice;
- forgetting the space needed to clean the heat exchanger;
- leaving the lines unprotected against impacts and the elements.
The visible positioning in the photo preserves a service area beside the machine while keeping the adjacent door and passage accessible.
Rebates and the warranty must be confirmed using the exact model number
Page 2 of the sheet lists separate AHRI numbers for ductless, ducted, and mixed configurations, as well as an indication of eligibility for local rebates.
Actual eligibility, however, depends on the outdoor model, the combined indoor units, the program available at the time of application, and the documents provided. It is not enough for the series name to appear on a list: the complete combination and applicable reference number must be verified.
The document also indicates a standard 10-year warranty, with an additional two-year extension subject to certain registration and proof-of-installation requirements with the distributor.
We verify these conditions when preparing the estimate so that the client knows which information must be recorded and which documents must be kept, including the invoice, model numbers, serial numbers, and proof of installation.
An exterior finish that respects the building
The visible result of this installation is based on several simple but important choices: a single outdoor unit for three zones, a clean metal support, an accessible disconnect switch, grouped lines, and a vertically aligned line-set cover.
No pipe crosses the terrace at random, and the neighboring door remains unobstructed. The outdoor unit is accessible without unnecessarily occupying the circulation area. The light-colored line-set cover also limits contrast with the brick and existing architectural elements.
This attention is particularly useful in Montreal, where outdoor space is limited, but it also applies to balconies in Laval, townhouses in Longueuil, properties on the North Shore, and residences on the South Shore.
Each area presents different constraints. The method remains the same: measure, calculate, plan access, protect the building, and carry out a complete commissioning.
At AirGreen, we do not select a 3-head heat pump based solely on price or total BTUs. We check the capacity by zone, the electrical panel, piping lengths, condensate management, the outdoor unit’s location, and the possibility of servicing the equipment for years after installation.
It is this preparation that transforms a compact installation into a durable, quiet system that is truly suited to the building.