A multi-zone installation where the location of each head matters just as much as the system’s capacity
On this installation completed in The Presentation, one of the three indoor units of the GREE FREEMATCH R32 heat pump had to find its place in a room whose layout left very little room for maneuver. The photo taken during commissioning shows a wall-mounted head installed very high on a wall with vertical panels, immediately beneath a ceiling made of perforated acoustic panels. A wall-mounted light fixture already occupies the lower-left portion of the available surface.
The result may seem simple: a white GREE unit, well positioned, with its air outlet louver open and its digital display illuminated. Yet this apparent simplicity rests on several technical decisions. The air intake above the unit had to be kept clear, airflow had to remain unobstructed, the existing light fixture had to be avoided, the drainage slope had to be maintained, and this head had to be connected to the system’s two other zones without creating an unnecessarily complex piping route.
The display visible in the photo reads 61. The image alone does not make it possible to determine with certainty whether this is the displayed room temperature, a setpoint in degrees Fahrenheit, or a parameter temporarily shown during testing. What we can observe, however, is that the head is powered on and the lower louver is open, which corresponds to an operating or post-installation verification stage.
A head positioned beneath an acoustic ceiling: a constraint that must be measured precisely
The ceiling visible on this project is not a simple drywall surface. It features perforated acoustic panels that form a particularly pronounced horizontal line just above the heat pump.
In this situation, the height of the indoor unit must be selected precisely.
A wall-mounted head must retain enough space above it to allow for:
- intake of ambient air;
- opening of the front panel;
- removing and cleaning the filters;
- normal airflow toward the evaporator;
- reasonable access for future HVAC maintenance.
Installing the head as high as possible is therefore not automatically the best solution. A few extra centimeters can improve the appearance, but if they reduce airflow intake too much or prevent the panel from opening, the installation becomes less practical and potentially less efficient.
On this project in The Presentation, we used the available strip of wall between the ceiling and the elements below, while leaving the space required for the head to operate.
A unit that also had to work around an existing light fixture
To the left of the unit is a wall-mounted light fixture protected by a grille. This type of element may seem secondary when designing a heat pump system, but it directly affects where we can drill and route the lines.
We must specifically avoid:
- to place the head directly above a light fixture that produces a lot of heat;
- to make the light fixture difficult to replace;
- to route the lines through an area where electrical wiring is already present;
- to create an air outlet immediately blocked by existing equipment.
A good wall-mounted air conditioner or heat pump installation therefore starts by examining everything already present in the room: lighting, outlets, switches, electrical boxes, trim, suspended ceilings, doors, cabinets, and furniture.
The available wall may seem large at first glance, but the portion that can actually be used is much smaller once all these constraints are taken into account.
Why a three-head configuration suited this type of building
A three-head heat pump can serve three independent zones with a single outdoor unit. The FREEMATCH R32 system is specifically designed for this type of configuration.
In a building with several enclosed rooms or areas with different needs, a single head located in a central area does not always distribute air effectively. A closed door is sometimes enough to almost completely isolate a room.
With three indoor units, heating and cooling can be distributed directly where they are needed.
The three zones could, for example, correspond to:
- a main room and two bedrooms;
- three offices;
- a ground floor, an upper floor, and a basement;
- three sections of a commercial space;
- rooms with different sun exposures;
- spaces used on different schedules.
Each head can have its own temperature setpoint. Occupants therefore do not have to maintain exactly the same temperature everywhere.
However, the units share the same outdoor unit. They generally need to operate in a compatible mode: with this type of residential multi-zone system, one head is not normally used for heating while another provides cooling at the same time.
Up to 21 SEER2 and heating operation rated down to -30°C
The technical documentation provided for the GREE FREEMATCH R32 claims efficiency of up to 21 SEER2, 12.5 EER2 and 10 HSPF2. It also indicates an operating range of -30°C to 48°C in cooling mode and -30°C to 24°C in heating mode.
These features are particularly useful in Quebec's climate, where the same system may need to provide cooling during a hot period in July and operate as a heating system several months later.
The document also specifies that the range includes:
- self-diagnosis;
- intelligent defrosting;
- automatic voltage adaptation;
- advanced inverter technology G10;
- quiet operation;
- up to seven different indoor unit options;
- an A2L leak-detection sensor;
- powering the indoor units from the outdoor unit.
G10 inverter technology plays an important role in a three-zone system. Demand is not constant: one room may require heating in the morning, then two or three zones may be called on later. The compressor adjusts its operation rather than relying solely on full-capacity on/off cycles.
Which outdoor unit should be chosen for three indoor units?
The range includes five outdoor capacities in the documentation, but not all of them can accommodate three heads.
The model GWHD(18)ND6MO at 18,000 BTU/h is limited to two indoor units. A three-head configuration must therefore use one of the following models:
| GREE FREEMATCH R32 model | Connectable heads | Rated cooling | Rated heating |
|---|---|---|---|
| GWHD(24)ND6MO | 2 to 3 | 24,000 BTU/h | 24,000 BTU/h |
| GWHD(30)ND6MO | 2 to 4 | 28,400 BTU/h | 30,000 BTU/h |
| GWHD(36)ND6MO | 2 to 4 | 36,000 BTU/h | 36,000 BTU/h |
| GWHD(42)ND6MO | 2 to 5 | 42,000 BTU/h | 44,300 BTU/h |
The specification sheet indicates a power supply of 208/230 V for each of these units.
The photo of the indoor head in La Présentation does not make it possible to identify with certainty the exact outdoor unit used on this project. We therefore avoid assigning a precise capacity to the project without the corresponding nameplate.
Why we never size a system solely based on the number of rooms
Three rooms do not automatically mean three heads with the same capacity.
A small, well-insulated bedroom and a large room with several windows can have very different thermal loads. We must evaluate each zone separately.
Among the factors that influence our selection:
- floor area and volume of the room;
- ceiling height;
- insulation level;
- amount of glazing;
- orientation relative to the sun;
- number of exterior walls;
- floor where the room is located;
- air infiltration;
- heat-generating equipment;
- room occupancy;
- desired temperature;
- likelihood that all three zones will operate at high capacity at the same time.
The head shown in the photo is installed in an environment where the lighting and interior materials differ from those of a typical residential bedroom. Sizing must take the actual use of the space into account rather than relying on a simple square-footage rule.
The total capacity of the heads is not always the same as the compressor’s capacity
This is a particularly important point when comparing quotes for a multizone heat pump.
If three heads total, for example, 36,000 BTU/h on their nameplates, this does not automatically mean that the outdoor unit will provide 36,000 BTU/h for each of their simultaneous demands.
The outdoor unit has its own nominal capacity and distributes it among the indoor units.
Manufacturers allow certain combinations in which the sum of the indoor capacities exceeds the outdoor unit's nominal capacity, because not all rooms necessarily demand their maximum at the same time.
However, this design must comply with the approved combinations. Adding heads and totaling their BTUs without checking the manufacturer's data is not a sizing method.
Behind the wall-mounted head: lines, drainage, electrical connections, and commissioning for the three zones
Three heads mean three routes that must be organized properly
Each indoor unit in the system has its own connection to the outdoor unit.
We need to plan for each zone:
- a liquid refrigerant line;
- a gas refrigerant line;
- the appropriate wiring;
- communication with the outdoor unit;
- a condensate drainpipe.
The FREEMATCH R32 technical sheet specifies fittings of 1/4 in. on the liquid side and 3/8 in. on the gas side. The maximum total lengths vary according to the outdoor unit and can reach 60 m, 80 m, or 100 m for models that can accommodate three heads. The maximum permitted height difference is 15 or 25 meters, depending on the model.
This flexibility is useful when the three heads are distributed across different sections of the building.
Nevertheless, we always try to avoid unnecessary detours. A long line adds materials, complicates the finish, and may require an additional amount of refrigerant.
The R32 charge also depends on the actual route
The documentation provides a different precharged length for each outdoor unit and specifies an additional refrigerant charge when the lines exceed that length.
This step must not be estimated approximately.
We need to know:
- the length of each circuit;
- the total length;
- the outdoor unit model;
- the amount of R32 already included by the manufacturer;
- the additional amount required according to the documentation.
An installation may appear to function properly even if its charge is not optimal. The consequences may instead appear when the outdoor temperature becomes very high or very low and the system is heavily used.
Drainage: invisible in the photo, essential to the installation
In the photo from La Présentation, no drainpipe is visible beneath the head. This simply indicates that the route is concealed or outside the frame; we cannot determine its exact path from the image.
Each head must still drain the water produced during air conditioning.
The evaporator cools the air below its dew point, and the moisture turns into condensate. This water falls into a pan inside the unit and must then leave the building.
Proper drainage requires:
- a continuous slope when drainage operates by gravity;
- no crushed tubing;
- watertight connections;
- an appropriate outlet point;
- a real test with water before leaving the site.
A negative slope may appear to work without problems on a dry day, then cause a leak during a very humid period.
Why we test each indoor unit independently
A three-indoor-unit installation cannot be validated by merely powering on the outdoor unit.
Each circuit must be tested.
We specifically check:
- startup of the first zone;
- startup of the second;
- startup of the third;
- operation of multiple units simultaneously;
- louver movement;
- fan speed;
- supply-air temperature;
- electronic communication;
- condensate drainage;
- presence of vibrations or abnormal noises.
The indoor unit visible in the photo is already operating with its louver open. The illuminated display is precisely a characteristic detail of this inspection stage.
A wiring error between the three zones can be difficult to diagnose afterward
On a multi-zone system, each set of refrigerant lines must correspond to the correct communication wiring.
We therefore identify the circuits during installation.
If indoor unit A is connected through the refrigerant lines to port A on the outdoor unit, but its wiring is associated with port B, the system may generate errors or behave inconsistently.
This precaution is even more important when the three indoor units are far from one another and the lines converge at the same outdoor location.
Systematic labeling at the start of the project prevents having to trace each line after the finish work.
Electrical requirements vary by outdoor unit model
All the FREEMATCH units shown operate at 208/230 V, but their current requirements are not identical.
For models that can supply three indoor units, the specifications indicate:
- GWHD(24)ND6MO: MCA 19.5 A and maximum protection 25 A;
- GWHD(30)ND6MO: MCA 23 A and maximum protection 35 A;
- GWHD(36)ND6MO: MCA 30 A and maximum protection 45 A;
- GWHD(42)ND6MO: MCA 30 A and maximum protection 45 A.
This table explains why we need to know the exact model before confirming the circuit requirements.
Replacing an old heat pump does not guarantee that the existing circuit breaker and wiring will automatically be suitable for the new system.
A heating range down to -30 °C does not mean constant capacity
The documentation states that heating operation is available between -30 °C and 24 °C.
This data indicates the platform’s operating range. It does not necessarily mean that the unit maintains its full rated capacity at -30 °C.
For a residence at The Presentation, we should instead verify whether the selected system meets the building’s heat loss when temperatures drop sharply.
This distinction becomes even more important with three zones. If all three heads demand substantial heating simultaneously, they must share the outdoor unit’s capacity actually available at that temperature.
SEER2, HSPF2, and EER2: what the figures allow you to compare
The technical table indicates SEER2 of 21 and a an HSPF2 of 10 for the models presented. EER2 ranges from 12 to 12.5 depending on capacity.
SEER2 is mainly used to compare seasonal cooling efficiency, while HSPF2 concerns heating over a season.
These indicators are useful when several homeowners compare models with Montreal, Laval, Longueuil, on the North Shore or the South Shore, but they do not replace proper sizing.
A highly efficient heat pump on paper can still deliver disappointing results if:
- it is improperly sized;
- the heads are poorly positioned;
- the lines are inadequate;
- the refrigerant charge is incorrect;
- airflow is blocked;
- maintenance is neglected.
Mistakes to avoid during an installation like the one in La Présentation
Installing the head too close to the acoustic ceiling
The upper space must allow for air return and filter access. The pursuit of a compact finish must not interfere with operation.
Ignoring existing electrical components
The visible light fixture on the wall reminds us that before drilling, we need to know what may be behind the finish.
Automatically choosing three identical heads
Each zone must be sized according to its actual needs.
Neglecting the drain because it is concealed
A concealed drain must be tested even more carefully, since it will be more difficult to access after finishing.
Forgetting the outdoor unit’s shared capacity
The sum of the BTUs listed on the heads is not a guarantee of simultaneous capacity.
Confusing minimum operating temperature with full capacity
The fact that a unit operates at -30 °C does not mean that its performance is identical to that achieved at a milder outdoor temperature.
AHRI, ENERGY STAR, and rebate programs
Page 2 of the sheet provides distinct AHRI numbers for ductless, ducted, and mixed systems, and these references change according to the outdoor unit.
This information is important when an installation is used for a grant or rebate application.
The actual combination must be verified, not just the FREEMATCH R32 brand or name.
The documentation also presents the system as eligible for local rebates. However, the applicable criteria and amounts must be confirmed according to the current program, outdoor model, indoor units, AHRI combination, building type, and date of the work.
Warranty: why registering the equipment is important
The sheet indicates a 10-year standard warranty, along with the possibility of an additional two-year extension with Wolseley when the registration and/or proof-of-installation requirements are met.
After installation, we recommend keeping:
- the detailed invoice;
- the outdoor unit model;
- the models of the three heads;
- serial numbers;
- the applicable AHRI number;
- photographs of the rating plates;
- registration confirmation;
- documents related to a potential rebate request.
This information is much easier to archive on the day of installation than to retrieve several years later.
Maintenance of a unit installed very high
Positioning the unit high up frees up the room and generally improves air distribution, but the filters must remain accessible.
Routine cleaning includes, among other things:
- removing and cleaning the filters;
- inspecting the air intake;
- checking the louver;
- monitoring noise;
- checking condensate drainage.
With three indoor units, this routine must be repeated in each zone.
A unit installed in a dustier room may require more attention than one located in a bedroom. Therefore, the same cleaning interval should not necessarily be applied to all three units.
An AirGreen installation adapted to the reality of the building in La Présentation
This installation of a three-head GREE FREEMATCH R32 heat pump in La Présentation clearly shows that the most important details are not always the ones that appear on a technical data sheet.
The head visible in the photo had to be integrated:
- beneath a perforated acoustic ceiling;
- in a high and relatively narrow area;
- above a wall already occupied by a light fixture;
- with sufficient access for the filters;
- without obstructing the louver’s movement;
- while remaining properly connected to the system’s two other units.
The technical work continues behind the finish: selecting the multi-zone combination, calculating refrigerant line lengths, drainage, circuit identification, evacuation, R32 verification, electrical connections, and testing the three zones.
At AirGreen, it is precisely this combination of details that guides our heat pumps and HVAC installation in Montreal, Laval, Longueuil, the North Shore, the South Shore, and elsewhere in Montérégie. A high-performance system does not begin when you press the remote control. It begins with equipment selection, followed by an installation suited to the geometry and actual use of each space.
On this La Présentation project, the result is a compact indoor unit discreetly positioned in the upper part of the wall and integrated into a three-head GREE FREEMATCH R32 multi-zone heat pump designed to provide more precise comfort control in various building sectors.