A wall-mounted unit installed above a door: a compact location requiring particularly precise installation
In Saint-Liboire, in Montérégie, this installation of a GREE FREEMATCH R32 3-head heat pump illustrates a reality we regularly encounter at AirGreen: the best location for an indoor unit is not always a completely unobstructed wall. In some rooms, it is necessary to work around doors, windows, furniture, decorative elements, and everyday traffic while maintaining effective air distribution.
The jobsite photo shows one of the three GREE wall-mounted units installed directly above an exterior door. The unit occupies the space between the top of the opening and the ceiling, an area that would otherwise be difficult to use. Its digital display shows a setpoint of 20 °C, while the lower louver is open and directed toward the room.
The photo was also taken while the finishing work around the door had not yet been fully completed. The outline of the opening remains visible, making it possible to see the project in a genuine construction phase rather than only after the final touch-ups. For us, it is precisely during these intermediate stages that several critical details are determined: the location of the opening, the routing of the lines, the drain position, the leveling of the wall plate, and future access to the unit.
The complete system includes three indoor units connected to a GREE FREEMATCH R32 outdoor unit. Each zone can thus have its own temperature setting without requiring three separate outdoor units.
Using the space above the door without sacrificing airflow
Installing a wall-mounted unit above a door can be an excellent solution when the room’s geometry allows for it. The area above a door is generally free of furniture, which keeps the side walls available for cabinets, artwork, curtains, or other arrangements.
However, this location requires much more methodical verification than a simple aesthetic choice.
The unit must retain sufficient space above it to allow air intake. It must also have adequate clearance below the outlet so the louver can open normally and direct air into the room.
In the Saint-Liboire photo, the indoor unit is centered above the opening, and its air outlet remains completely unobstructed. Nothing is installed directly in front of the louver.
This arrangement allows the conditioned air to be projected into the room rather than being blocked by a tall piece of furniture or a nearby partition.
Why the space between the heat pump and the ceiling is important
A wall-mounted heat pump does not simply blow air from its lower section. It must first draw in room air, generally through the upper part of its casing.
If the indoor unit is installed too close to the ceiling, the air intake may be restricted.
This can affect:
- the actual airflow;
- the noise level;
- how easily the filters can be removed;
- access during a deep cleaning;
- the efficiency of heat exchange;
- the ability to open the front panel properly.
In this project, we had to make use of a relatively narrow strip of wall between the door and the ceiling. This type of installation therefore requires checking the unit’s physical dimensions before the first hole is drilled, and not after preparing the lines.
A few centimeters can make the difference between an easily accessible indoor unit and one that is difficult to service over the next ten years.
An air outlet positioned away from obstacles
The open louver visible in the photo helps show the direction of the airflow.
In cooling mode, cooled air tends to descend naturally. We generally seek to promote sufficiently deep projection into the room so that this air does not immediately fall beneath the indoor unit.
In heating mode, the strategy may change because warm air naturally rises. A more downward orientation can then help direct heat toward the occupied area.
Positioning the unit above the door offers an advantage here: the unit has a large clear area in front of it.
It is not installed:
- behind a bookcase;
- in a recess;
- directly above a large cabinet;
- facing a partition located a few feet away;
- behind a curtain.
The indoor unit can therefore use its louver to distribute air throughout the room according to the selected mode.
An exterior door beneath the indoor unit: drainage becomes particularly important
The least visible detail of a wall-mounted unit is often the one that can cause the greatest damage if it is improperly installed: the condensate drain.
In cooling mode, the moisture in the air condenses on the indoor unit’s cold coil. This water falls into a drain pan and must then be discharged.
When the heat pump is located above a door, we pay particular attention to this circuit. A leak must obviously not end up above the frame, on the door, or inside the wall.
For this type of installation, our procedure is to check the drain route, avoid backslopes and crushed sections, then verify the discharge before considering commissioning complete.
When the configuration allows for gravity drainage, a continuous slope remains preferable. When that is not possible, the solution must be planned during the route design rather than added after a problem appears.
The photo also shows why we coordinate our work with renovations
The framing around the door has not yet been covered with its final finish in the photo.
For an HVAC team, working during this phase of a project can offer an interesting opportunity: certain sections of piping, wiring, or drainage can be planned before the moldings and touch-ups are completed.
However, we must coordinate our work carefully so that the future finishing can be completed without moving the equipment.
The head must remain removable for future maintenance. Never use new moldings or finishing products in a way that traps the casing against the wall.
This foresight is part of our work on renovation projects in Saint-Liboire, but also in older housing units in Montreal, homes in Laval, properties in Longueuil, as well as in North Shore and the South Shore.
Three heads for three zones that do not experience the same temperatures
One of the main reasons to choose a multizone heat pump is to no longer depend on a single heating or cooling point for several rooms.
One head can serve the main living area, while the other two handle bedrooms, an office, a floor, or another more isolated section of the property.
Each zone does not necessarily have the same thermal load.
A room with extensive glazing can heat up quickly in the afternoon. A bedroom on the opposite side of the house may stay cooler. An upper floor often accumulates more heat in summer than a lower level.
With three indoor units, we can bring conditioning closer to where the need actually exists.
Three heads do not mean three outdoor units
The principle of a GREE FREEMATCH R32 consists of connecting multiple indoor units to a single outdoor unit.
GREE documentation specifies that the outdoor unit GWHD(24)ND6MO can power two or three indoor units. The GWHD(30) and GWHD(36) models accept two to four, while the GWHD(42) can accommodate up to five.
For a three-indoor-unit installation such as the one in Saint-Liboire, several outdoor units in the range may therefore be compatible.
The exact outdoor unit number and the capacity of each of the three indoor units are not visible in the photographic documents provided for this project. We therefore do not assign them a BTU value that cannot be confirmed.
The sheet nevertheless shows that the outdoor units compatible with three indoor units cover, among other things, rated cooling capacities from 24,000 to 42,000 BTU/h, depending on the selected version. The rated heating capacities also vary by outdoor unit and can reach 44,300 BTU/h on the largest model shown.
Why we never size a multizone system simply by adding up the BTUs
A common mistake is to choose three indoor units, add up the capacities shown on their nameplates, and automatically select an outdoor unit corresponding to the same total.
A multizone system does not operate exactly this way.
The outdoor unit shares its capacity among the indoor units requesting heating or cooling at a given time. A bedroom that has already reached 20 °C may require very little capacity while the main living area is still operating at a higher load.
Before selecting a combination, we analyze in particular:
- the needs of each zone;
- the floor area and ceiling height of the rooms;
- insulation;
- the windows and sun exposure;
- air infiltration;
- the layout of the floors;
- the outdoor unit’s capacity;
- the combinations authorized by the manufacturer;
- the simultaneous demand of the three units;
- heating needs during cold periods.
This step protects both comfort and system modulation.
An oversized outdoor unit may have more difficulty when only a small indoor unit is requesting capacity. Conversely, an undersized unit may become insufficient when all three zones require substantial heating simultaneously.
Efficiency, R32 technology, and technical details of the GREE FREEMATCH installed in Saint-Liboire
Up to 21 SEER2, 12.5 EER2, and 10 HSPF2
The documentation provided for the GREE FREEMATCH R32 advertises efficiency of up to 21 SEER2, 12.5 EER2 and 10 HSPF2.
These ratings are used to compare equipment efficiency under standardized conditions.
The SEER2 concerns seasonal cooling efficiency, while HSPF2 is associated with seasonal heating. EER2 complements this information with an efficiency measurement under specified conditions.
The technical sheet on page 2 indicates a SEER2 of 21 and an HSPF2 of 10 for the five outdoor units in the range shown.
Actual performance in a residence, however, depends heavily on the installation. A poorly positioned head, clogged filters, an obstructed outdoor unit, or an incorrectly sized system can reduce the expected benefits of a machine that is efficient on paper.
Heating and cooling in Quebec conditions
The brochure's first page indicates a cooling operating range of -30 °C to 48 °C and a heating range of -30 °C to 24 °C.
This wide operating range is particularly relevant in our climate, where the same installation must transition from hot, humid periods in summer to strongly negative temperatures in winter.
However, it is important not to confuse minimum operating temperature and capacity available at that temperature.
The fact that a heat pump can continue operating at -30 °C does not automatically mean that it produces exactly its rated capacity under those conditions.
When we evaluate an installation intended to make a meaningful contribution to winter heating, we also take into account the building's load and the supplementary heating strategy.
G10 Inverter technology truly comes into its own in a three-zone system
GREE's documentation notably presents G10 Inverter technology, intelligent defrosting, self-diagnosis, automatic voltage adaptation, and quiet operation. It also specifies that the indoor units are powered by the outdoor unit.
Inverter technology is particularly important in a multi-zone configuration.
Demand is practically never identical in all three rooms.
At one point, all three units may be operating. A few minutes later, the head visible in the photo may reach its 20 °C setpoint and reduce its demand. The outdoor system must then adapt its operation to the zones that continue to require capacity.
This modulation helps maintain more consistent temperatures and avoid a constant succession of full-load starts.
An important detail about how the three heads operate
The three units can receive different setpoints, but they share the same outdoor refrigeration system.
It is therefore best to avoid conflicting commands in which one head attempts to heat while another calls for cooling.
For simple operation, we generally recommend selecting the mode corresponding to the season for the entire system, then adjusting the desired temperature in each zone.
Thus, one room can be maintained at 20 °C while another is set differently, without the system modes conflicting.
R32 and A2L detection
The FREEMATCH uses R32. The documentation also indicates the presence of an A2L leak detection sensor included.
For our team, this refrigerant change does not make the standard installation steps any less important. On the contrary, the refrigerant connections must remain precise.
In a three-head heat pump, several refrigerant lines connect the units to the outdoor unit. This multiplies the connections that must be properly made and checked.
Our method for this type of project includes checking the connections, performing the applicable leak test, evacuating the circuit, and verifying the system before fully commissioning it.
The permitted distances make a multi-zone system appealing in a home with several rooms
Page 2 of the specification sheet presents maximum total pipe lengths ranging from 40 to 100 meters, depending on the outdoor unit, as well as maximum height differences of 15 to 25 meters.
This flexibility makes it possible to place three heads in different areas without necessarily concentrating all the units on the same exterior wall.
Nevertheless, the routes must be measured in reality.
The distance between a head and the outdoor unit is not a simple straight line. We must account for drops, rises, wall passages, changes in direction, and the sections needed to make the connections neatly.
The same section of the table also indicates the factory-charged line lengths by model and the requirements for adding refrigerant.
These data are verified according to the outdoor unit actually selected.
The electrical supply must follow the exact model
All outdoor units in the series presented in the specification sheet operate at 208/230 V.
However, electrical requirements vary with capacity.
The documentation indicates an MCA from 14.5 to 30 A and maximum overcurrent protection of 20 to 45 A depending on the outdoor unit.
For a three-head system, we therefore never determine the circuit breaker solely based on the number of indoor units.
The exact outdoor unit, its nameplate, the available electrical circuit, and the wiring gauge must be validated before the final connection.
An indoor unit above a door must remain easy to maintain
Using high spaces must not turn future maintenance into a complicated operation.
The filters of a wall-mounted head must be removable periodically. The front panel must open, and the internal parts must remain accessible during HVAC cleaning more complete.
In the photographed room in Saint-Liboire, the unit is not surrounded by fixed furniture.
This accessibility becomes important when we need to:
- clean the heat exchanger;
- check the condensate pan;
- inspect the drain;
- access the sensors;
- control the tangential fan;
- diagnose an error code.
An installation that appears discreet but prevents any future servicing is not a good installation.
The mistakes we want to avoid in this type of configuration
The visible location in this photo illustrates several points to check before installing a wall-mounted air conditioner or wall-mounted heat pump :
- do not place the head so close to the ceiling that the air intake becomes restricted;
- do not install the unit without confirming that the filters can be removed;
- do not position the louver facing a nearby obstacle;
- do not run a drain above a door without an appropriate slope;
- do not drill before confirming the route to the exterior;
- do not enclose the heat pump with future trim or finishing work;
- do not choose a head's capacity solely according to the room's size;
- do not set the three units of a multi-zone system to opposing modes.
These checks take little time compared with the years during which the system will be used.
The 20 °C display: a good example of zone control
In the photo, the head clearly displays 20 °C.
This image summarizes one of the practical advantages of a three-head heat pump: each zone can be adjusted according to its use.
The ideal temperature is not necessarily the same everywhere.
A room occupied in the evening can have a different setpoint from a bedroom or office used only during the day.
A multi-zone system provides this flexibility without requiring an outdoor compressor for each room.
However, to promote stable operation, we recommend avoiding excessive differences between spaces that are largely open to one another. Otherwise, two heads located in rooms that communicate directly may constantly attempt to correct the effects of the other zone.
ENERGY STAR, AHRI, and rebates: what the documentation actually confirms
On page 2 of the GREE sheet, and the visual shows the ENERGY STAR Cold Climate and AHRI Certified references. The table also provides different AHRI numbers for the non-ducted, ducted, and mixed configurations.
The same page includes the statement “Eligible for local rebates”.
However, the documentation provided specifies neither the program applicable to the Saint-Liboire installation nor the amount of any financial assistance.
We therefore avoid promising a rebate based solely on the name FREEMATCH R32.
To confirm eligibility, the exact combination of the outdoor unit and the three indoor units, the relevant AHRI number, and the program criteria in effect when the application is submitted must be verified.
A warranty worth documenting from day one
The sheet indicates a 10-year standard warranty and mentions an additional two-year extension with Wolseley when the product is registered and/or proof of installation is provided, subject to the conditions stated in the documentation.
For a three-head installation, we recommend keeping the information for the entire system, not just that of the outdoor unit:
- model and serial number of the outdoor unit;
- models of the three indoor units;
- serial numbers of the three heads;
- installation date;
- invoice;
- registration documents;
- applicable AHRI reference.
This documentation greatly simplifies the process several years later.
What this AirGreen installation in Saint-Liboire demonstrates particularly well
The distinctive feature of this project lies not only in the choice of a GREE FREEMATCH R32. It lies in the way an indoor unit has been integrated into a very specific section of wall.
The head occupies the space above the door while leaving the side walls available. Its air outlet is not blocked. The display remains readable. The installation is high enough to distribute air throughout the room while taking into account the ceiling immediately above it.
The photo taken before the door surround was fully finished also shows the reality of a job site: an HVAC installation must be coordinated with the building as it is actually constructed, not only with an ideal plan on paper.
In a three-head system, this assessment must be repeated three times, since each indoor unit has its own room, its own obstacles, and its own path to the outdoors.
This is the approach we apply at AirGreen in Saint-Liboire and everywhere we carry out HVAC installations, whether in Montréal, Laval, Longueuil, on the North Shore or the South Shore sizing according to actual needs, making smart use of the available space, protecting the drainage, keeping the equipment accessible, and finishing with a methodical commissioning process.
A high-performance multi-zone heat pump starts with good equipment. Your daily comfort then depends on hundreds of small installation choices that are rarely noticed once the work is complete.