Installation of a MIDEA MIDEA 28 dual-zone heat pump in Sainte-Anne-de-Sabrevois

A dual-zone installation designed to distribute comfort without multiplying the number of outdoor units

In Sainte-Anne-de-Sabrevois, we completed an installation that clearly illustrates the value of a MIDEA MIDEA 28 dual-zone heat pump when a homeowner wants to cool and heat two separate spaces while keeping the outdoor installation relatively simple. Rather than installing two independent systems, this configuration makes it possible to connect several indoor units to a single outdoor unit, with controls adapted to the needs of each zone.

This is precisely the principle behind a MIDEA multi-zone system: a single outdoor unit supplies several indoor units, which can be adjusted individually according to the desired temperature in each room. MIDEA documentation also emphasizes that this type of system makes it possible to heat or cool only the spaces in use, rather than unnecessarily conditioning an entire home.

In this project, the visible result indoors is intentionally discreet. In the installation photo, we see a MIDEA wall-mounted unit installed very close to the ceiling, in a space where the wall geometry required carefully planned placement. The choice of height, module alignment, and routing of the connections are details that may seem minor but have a direct impact on the final appearance, airflow, and overall quality of the HVAC installation.

Why choose a dual-zone heat pump instead of two separate systems?

In a home with two areas that have different needs, a dual-zone heat pump offers several practical advantages.

Each indoor unit has its own control. A bedroom can therefore be maintained at a different temperature from an open area, living room, office, or floor. MIDEA states that individual control of each unit makes it possible to adapt comfort room by room and reduce consumption by avoiding heating or cooling unused spaces.

This approach is particularly interesting in Sainte-Anne-de-Sabrevois and elsewhere in Montérégie, where residences often have very different layouts from one floor to another: additions, attic bedrooms, open living rooms, finished basements, or sections of the house added over the years.

Instead of trying to force a single wall-mounted unit to distribute its air throughout the property, we can distribute the capacity between two strategic zones.

The benefit is twofold:

• greater temperature uniformity;
• more precise control in each area;
• a single outdoor unit;
• less space occupied around the house;
• more flexible use depending on the time of day;
• a potential reduction in unnecessary operation in unoccupied rooms.

MIDEA also highlights the advantage of a single outdoor unit for several indoor units, which reduces the space required outside and can limit the number of noise sources around the property.

MIDEA 28: a multi-zone platform that is much more flexible than a simple two-room system

The name MIDEA 28 refers to a family of multi-zone systems capable of accommodating several residential configurations. In the technical documentation provided by MIDEA, the Extreme Heat model in this category is identified as MO4HX-H27B-2A, with a nominal capacity of approximately 27,000 BTU/h and an architecture allowing multiple indoor connections.

The brochure associates this model with reference number AHRI 215471460. It also indicates a cooling and heating capacity of 27,000 BTU/h for the non-ducted reference combination, a SEER2 of 23, an EER2 of 12.5, and an HSPF4 index of 10.5.

These figures are important, but we never select a heat pump solely based on the BTU rating listed in a brochure.

In a dual-zone installation, the following must also be assessed:

• the area of each zone;
• ceiling height;
• solar orientation;
• the number of windows;
• the level of insulation;
• communication between the rooms;
• the possible locations for the wall-mounted units;
• the distance between the indoor units and the outdoor unit;
• the actual distribution of heating needs.

Two homes of the same size may therefore require very different configurations.

Inverter technology suited to load variations

A multi-zone system does not constantly operate at maximum capacity. Inverter technology allows the compressor and fan motors to modulate their operation according to the actual demand.

MIDEA specifies that the system adjusts its capacity when the ambient temperature changes and can operate at partial load when all rooms do not need heating or cooling simultaneously.

This is particularly relevant in a two-zone installation.

Imagine that in the evening only one bedroom needs additional heating while the second zone has already reached its setpoint. The system does not need to operate in the same way as it would if both spaces simultaneously required high heat output.

This modulation is one of the fundamental differences between a modern multi-zone heat pump and several older systems operating according to a much simpler on-off logic.

The positioning of the wall-mounted unit: a decisive detail in this installation

The photo of our installation in Sainte-Anne-de-Sabrevois shows an interesting situation: the indoor unit is installed in the upper part of the wall, immediately beneath a ceiling junction.

In this type of situation, we must take several constraints into account simultaneously.

The space available above the appliance

A wall-mounted unit draws a significant portion of its air from above. Its placement must therefore comply with the model’s specific installation requirements and allow appropriate access to the appliance.

Installing a head simply “as high as possible” is not a professional method. Before drilling, we must check the clearances, the wall structure, the drain path, and the possibility of carrying out HVAC maintenance if necessary.

The air path

A properly installed indoor unit should direct its air toward the occupied space without unnecessarily creating an uncomfortable draft zone.

We consider in particular:

• the position of beds and sofas;
• opposing walls;
• openings to other rooms;
• ceiling height;
• architectural obstacles;
• natural air circulation.

The best location is therefore not necessarily the one that simplifies the installer’s work. Instead, we seek the most sensible balance between performance, aesthetics, drainage, accessibility, and air distribution.

A compact wall-mounted unit with genuine air-moving capacity

The MIDEA multi-zone lineup includes several wall-mounted unit formats. The documentation specifically features the All Easy Pro units, available in different capacities.

Depending on the model, dimensions and airflow rates vary considerably. For example, the wall-mounted units in this series use a 208/230 V single-phase, 60 Hz power supply, with multiple fan speeds. The documentation also shows that the smaller models can operate at very low sound levels at reduced speed, with some tables indicating values as low as around 20 dB(A), depending on capacity and operating mode.

For the homeowner, this means that a properly selected system does not need to operate continuously at high speed to maintain comfort.

Two zones do not mean two identical capacities

A common mistake when planning a dual-zone heat pump is assuming that it is enough to divide the total capacity in half.

That is not how we design an installation.

A large, sun-facing open area and a small bedroom obviously do not have the same heating and cooling load. Installing two units with identical capacities simply because the system has two zones can lead to improper operation, particularly in the smaller space.

At AirGreen, we instead assess each zone separately before considering the behavior of the system as a whole.

It is also important to understand that with a multi-zone system, the sum of the rated capacities listed for the indoor units does not necessarily correspond to the output all units can provide simultaneously.

MIDEA states this explicitly in its combination rules: when the total capacity of the indoor units exceeds the outdoor unit’s rated capacity, the available capacity for each unit may be reduced, and this effect is particularly noticeable in heating mode.

This is essential information when sizing an installation for Quebec’s climate.

What this MIDEA installation in Sainte-Anne-de-Sabrevois teaches us about a good multi-zone project

The quality of the result begins before the tools arrive

A large part of the success of a heat pump installation is determined before the first hole is even drilled in the wall.

For a dual-zone configuration, we must already have determined:

1. the appropriate capacity of the outdoor unit;
2. the capacity of each indoor unit;
3. their locations;
4. the route of the refrigerant lines;
5. the slope and route of the condensate drains;
6. the required electrical supply;
7. the outdoor location that complies with the manufacturer’s clearance requirements;
8. future accessibility for maintenance.

When these elements are considered together, the final installation generally appears much simpler than it really was.

That is precisely what we are looking for: a clean installation that does not look as though it was improvised around the building’s obstacles.

One outdoor unit, but several circuits to manage correctly

On a single-zone heat pump, the connections are relatively straightforward: one indoor unit, one outdoor unit, and a pair of refrigerant lines.

On a MIDEA multi-zone heat pump, each indoor unit must be properly paired with the outdoor system.

MIDEA has incorporated a technology called SynchroConnect into this product line, designed to make it easier to verify the connections between the cables and refrigerant lines. The documentation explains that the system can diagnose the status of the connections and synchronize the circuits with the wiring when they are properly connected.

This feature is useful, but it obviously does not replace a meticulous installation.

We always check the connections, condensate drains, electrical connections, and the operation of each zone before considering the project complete.

The mistake to avoid: choosing the number of BTUs based solely on the floor area

The rough “BTUs per square foot” rule can serve as a very approximate starting point, but it should never be used as the sole sizing method.

A recently built home in Sainte-Anne-de-Sabrevois with a high-performance envelope will not have the same heat losses as an older residence of the same size.

The same principle applies to Montréal, Laval, Longueuil, the North Shore, and the South Shore.

A thorough assessment must take into account the windows, exposure, insulation, and how the different zones communicate with one another.

An oversized unit may run unnecessary cycles and provide less comfortable regulation. An undersized unit, on the other hand, may run continuously during the most demanding periods.

The other mistake: believing that all zones are completely independent

The temperatures can be adjusted individually, but the indoor units still belong to the same refrigeration system.

This distinction is important.

A dual-zone installation provides excellent adjustment flexibility, but it is not equivalent to two fully independent heat pumps, each with its own outdoor compressor.

That is precisely why the selection of indoor and outdoor capacities must be made as a complete HVAC system, rather than as an addition of two wall-mounted units.

Why the MIDEA 28 range is interesting for complex residential projects

The manufacturer's documentation shows that this platform is not limited to wall-mounted units. MIDEA provides an architecture compatible with various indoor units, including wall-mounted units, consoles, cassettes, and ducted systems.

This modularity becomes particularly valuable when the home does not allow the same type of unit to be used in every room.

In another project, for example, a wall-mounted unit might be suitable for the living room, while a compact ducted unit would be preferable for an area containing several small rooms.

The MIDEA brochure also features High Static Slim Duct and Low Static Slim Duct units, as well as air-handling units, confirming that the platform was developed to go far beyond a simple traditional wall-mounted configuration.

What we check before handing the system over to the owner

When commissioning a MIDEA dual-zone heat pump, we pay particular attention to how the two zones operate.

We check in particular:

• startup of the indoor units;
• response to setpoint changes;
• ventilation;
• drainage;
• operation of the outdoor unit;
• absence of abnormal vibrations;
• connection stability;
• clearance around the equipment;
• communication between the different components.

We also explain how a multi-zone system works to the homeowner. This step prevents many misunderstandings after installation.

A discreet result indoors, but an installation that requires precision

In the photo of this Sainte-Anne-de-Sabrevois project, the white wall-mounted unit intentionally blends into the décor. This is often a sign of a successful installation: the technology is present, but it does not visually dominate the room.

This apparent simplicity nevertheless relies on several technical decisions made in advance: location, height, accessibility, line routing, drainage, and system selection.

This is the approach we apply in our multi-zone heat pump installations in Montréal, Laval, Longueuil, on the North Shore and the South Shore.

We are not simply looking to install a machine that starts up on the day of the work. We aim to set up a system that is coherent with the home, sufficiently accessible for future HVAC maintenance, properly sized, and pleasant to use every day.

Is a dual-zone heat pump suitable for your home?

It can be particularly relevant when two areas with different needs must be served, including:

• a ground floor and an upper floor;
• a primary bedroom and a common area;
• a house and an addition;
• a living room and an office;
• two separate sections of a dwelling;
• a room that is difficult to heat and a main area.

The final choice must nevertheless be based on the actual home.

At AirGreen, we assess the layout of the property before determining the capacity, number of indoor units, and their locations. This method allows us to propose an HVAC installation that takes into account both comfort and the building’s technical realities.

The installation completed in Sainte-Anne-de-Sabrevois with this MIDEA MIDEA 28 dual-zone heat pump is a good example: a clean, discreet multi-zone solution designed to give the homeowner much more precise control over their comfort.

For a dual-zone or multi-zone heat pump project in Montréal, Laval, Longueuil, on the North Shore, the South Shore, or elsewhere in Greater Montréal, we can assess the needs of each room and propose a configuration suited to the building rather than a standardized solution.