HITACHI airHome Multi 2-Head Wall-Mounted Heat Pump | 36,000 BTU Compressor

Two Comfort Zones, One Compressor: A Multizone Solution Designed for Greater Montreal Homes

The HITACHI airHome Multi 2-Head Wall-Mounted Heat Pump | 36,000 BTU Compressor is for homeowners who want to air condition and heat two distinct spaces without multiplying outdoor units. For a residence in Montreal, a condo in Laval, an intergenerational home in Longueuil, a bungalow on the North Shore or a family property on the South Shore, this system allows for the creation of two independent comfort zones, each with its own control.

At AirGreen, we often recommend this type of configuration when two rooms have very different needs: a sunny living room and a cooler bedroom, an open ground floor and a closed office, or a family area in the basement and a main room upstairs. The great advantage of a multi-zone wall-mounted heat pump is simple: a single outdoor unit can power several indoor units, while allowing each zone to operate according to its own set point.

In the case of the HITACHI RAM-G36N4HAA outdoor compressor, we are looking at a very interesting multi-zone platform for residential projects that require flexibility. According to the official Hitachi brochure, the airHome Multi series allows for air conditioning and heating up to 5 rooms individually, combining several types of indoor units, and integrating advanced filtration technologies to improve indoor air quality.

A 2-Head System Adaptable to Various BTU Combinations

The product page offers several possible zone combinations, including:

• 7,000 + 7,000 BTU
• 7,000 + 9,000 BTU
• 7,000 + 12,000 BTU
• 7,000 + 18,000 BTU
• 7,000 + 24,000 BTU
• 9,000 + 9,000 BTU
• 9,000 + 12,000 BTU
• 9,000 + 18,000 BTU
• 9,000 + 24,000 BTU
• 12,000 + 12,000 BTU
• 12,000 + 18,000 BTU
• 12,000 + 24,000 BTU
• 18,000 + 18,000 BTU
• 18,000 + 24,000 BTU

This variety is important, because a good HVAC installation isn't just about choosing the largest possible unit. It's necessary to evaluate the area, insulation, sun exposure, number of occupants, ceiling height, air circulation, openings between rooms, and how clients actually use their home.

In a typical Montreal home, for example, an open living room with a kitchen may require a stronger head than a closed bedroom. In a condo in Laval, two lower capacity heads can sometimes offer better comfort than a single oversized unit. On the South Shore, in some newer, better-insulated homes, we often find that a balanced combination yields better results than an overly aggressive system that constantly starts and stops.

Key Technical Specifications of the RAM-G36N4HAA Model

The RAM-G36N4HAA outdoor compressor provides a robust technical foundation for residential multi-zone installations. The information currently displayed on the AirGreen website indicates:

• Nominal Power: 36,000 BTU
• Cooling Capacity: 36,000 BTU
• Heating Capacity down to -20 °C
• Power at -8 °C: 25,000 BTU
• Power at -15 °C: 21,800 BTU
• Refrigerant: R-32
• AHRI: 216097708
• ENERGY STAR: Yes
• ENERGY STAR Cold Climate: No
• ENERGY STAR ID: 3799341
• WiFi: optional
• Voltage: 220 V
• MCA: 24 A
• MOP: 40 A
• Outdoor Sound Level: 56 dB(A)
• Outdoor Dimensions: 33.5 x 11.7 x 31.5 in
• Warranty: 10 years compressor, 10 years parts, 0 year labor
• LogisVert provincial subsidy indicated: $1,250, updated November 26, 2025

For clients comparing different wall-mounted heat pumps in Montreal, Laval, Longueuil, on the North Shore or South Shore, these details help to better understand where this product stands: it is not a simple basic wall unit, but a flexible multi-zone system, designed to offer distributed comfort across several rooms.

Why R-32 is an Important Point

The R-32 gas is increasingly present in new generations of heat pumps. For a homeowner, the interest lies mainly in energy efficiency and the evolution of industry standards. For our installation teams, R-32 also requires rigorous execution: adherence to piping lengths, clean flares, leak testing, micron vacuum pulling, connection verification, mechanical protection of conduits, and complete commissioning.

At AirGreen, we pay close attention to these steps, because a high-performance multi-zone heat pump on paper can lose a lot of efficiency if it is poorly installed. A bad flare, poorly insulated line, improperly planned drain slope, or unstable electrical communication between units can create problems that could have been avoided from the outset.

A 2-Zone Installation: What We Check Before Recommending the Configuration

Before proposing a HITACHI airHome Multi 2-Head Wall-Mounted Heat Pump, we analyze several elements on site:

1. The natural distribution of air
   A wall-mounted head does not heat an entire house through several closed doors. Locations must be chosen to maximize air reach without creating direct discomfort.
2. The distance between the outdoor unit and the indoor heads
   The path of the refrigerant lines influences cost, aesthetics, and performance. A too complex route may require more material, more protection, and more installation time.
3. Drainage possibilities
   Condensate must be evacuated correctly. In Montreal and older areas of Longueuil, architectural constraints can sometimes require a very precise solution to avoid unnecessary drain pumps.
4. Available electrical supply
   This model operates on 220 V, with a minimum circuit ampacity of 24 A and a maximum protection of 40 A. We always validate the electrical conditions before confirming the final offer.
5. The actual capacity required per zone
   A 10 x 12 ft room and a 700 sq ft open area should not be treated the same way. The choice between 7,000, 9,000, 12,000, 18,000 or 24,000 BTU must be consistent with actual needs.

Concrete Example: Two Zones in a South Shore Home

During a recent project on the South Shore, a client wanted to replace two old window air conditioners with a quieter and more aesthetic solution. The house had a very bright living room on the ground floor and a master bedroom upstairs. The client primarily wanted to improve summer comfort, but also wished to reduce the use of electric baseboards during milder autumn and spring periods.

A solution with a single larger wall unit would have created an imbalance: too much air in the living room, not enough in the bedroom. A 2-head configuration was more logical. The single outdoor compressor limited clutter in the yard, while the two indoor units provided much more precise control in each zone.

The most important point of the project was not just the choice of product. It was the exact placement of the heads, the discreet routing of lines, drain management, future access for HVAC maintenance, and external protection of the conduits. These are the details that transform a good machine into a durable installation.

Air Quality: An Often Underestimated Advantage

The HITACHI airHome Multi series is not limited to heating and air conditioning. The brochure highlights several elements related to air quality, including FrostWash technology, the PM2.5 activated carbon filter depending on compatible units, the ViroSense S filter for certain configurations, as well as the Mold Guard function which helps to dry internal components after air conditioning or dehumidification operations.

For customers in Montreal, Laval, and Longueuil, this aspect becomes particularly relevant in homes where summer humidity, urban dust, cooking odors, or allergens can affect daily comfort. A wall-mounted heat pump does not replace a complete ventilation system, but it can contribute to a more pleasant indoor environment when properly chosen, installed, and regularly maintained.

FrostWash and Mold Guard: Why These Functions Are Useful

The FrostWash function uses a freeze and thaw principle to help clean the evaporator coil. In practice, this can help maintain better airflow over time and limit the accumulation of contaminants on certain internal components.

The Mold Guard function, meanwhile, forces air through and dries internal components for about 60 minutes after air conditioning or drying operations, to help prevent odors and mold formation. In homes where air conditioning often runs during humid periods in July and August, this type of function can make a noticeable difference in daily use.

That said, we always explain to clients that no self-cleaning function replaces actual HVAC maintenance. Filters must be cleaned, drains must remain clear, coils must be inspected, and the outdoor unit must breathe freely.

A Quiet System, But Placement Remains Crucial

The indoor sound level varies depending on the selected head model. Information displayed on the page indicates a range of 30 to 42 dB(A) depending on the chosen model, while the brochure presents various wall-mounted units and other types of indoor units that can achieve very low levels depending on their capacity and fan speed.

In a bedroom, we prioritize positioning that avoids blowing directly towards the bed. In a living room, we look for an angle that distributes air without creating uncomfortable drafts. In a home office, we consider the workstation, perceived noise, and airflow direction.

This approach is particularly important in condos in Montreal and Laval, where exterior walls, balconies, condominium regulations, and distances from neighbors can influence the installation. A quiet device must also be installed intelligently.

Optional WiFi: Useful for Variable Schedules

Optional WiFi allows for remote control of the system with the compatible interface. For many clients, this is not just a gadget. A homeowner who works downtown but lives on the North Shore can adjust the heating before returning home. A family going away for the weekend can check settings remotely. A property manager can better control usage periods when a configuration allows it.

The brochure mentions the optional airCloud Go interface, which allows for programming operations and monitoring energy bills. For homeowners who like to optimize their consumption, this option can be a practical tool, especially in homes with variable occupancy.

Common Mistakes to Avoid with a Multi-Zone Heat Pump

A 2-head wall-mounted heat pump provides excellent results when properly sized and installed. Here are the mistakes we too often see during takeovers or service calls:

• Choosing two heads that are too powerful: this can lead to short cycling, less dehumidification, and uneven comfort.
• Installing a head in a hallway hoping to heat multiple rooms: air does not replace true room-by-room distribution.
• Neglecting drainage: a poorly sloped drain can cause water backups, odors, or damage.
• Placing the outdoor unit without considering snow: in Quebec, protection and clearance around the compressor are essential.
• Ignoring access for maintenance: a too-tight installation can complicate future inspections.
• Reusing lines without complete verification: any reuse must be accompanied by inspection, proper cleaning, and rigorous testing.

At AirGreen, we prefer to explain these points before installation rather than fixing problems afterward. This transparency is part of our way of working.

A Serious Solution for Two Zones, with AirGreen Support from Selection to Installation

The HITACHI airHome Multi 2-Head Wall-Mounted Heat Pump | 36,000 BTU Compressor is particularly suitable for customers who want a flexible, efficient, and clean solution to control two distinct zones. It integrates well into several types of properties: single-family homes, duplexes, condos, renovated apartments, extensions, finished basements, and telecommuting spaces.

Why choose AirGreen for this type of installation

A multi-zone installation requires more planning than a simple wall-mounted unit. It is necessary to coordinate the two heads, refrigeration lines, drains, electrical communications, outdoor positioning, weather protection, and full commissioning. Our teams are familiar with the realities of buildings in Montreal, Laval, Longueuil, the North Shore, the South Shore, and the Montérégie region.

We offer:

• A 100% free on-site estimate
• A recommendation based on the actual needs of each room
• A clear final offer before work begins
• A clean, professional, and compliant installation
• Experienced refrigeration technicians
• A serious approach to leak tests and vacuum pulling
• Accessible after-sales service
• HVAC maintenance options
• Civil liability insurance of $5,000,000
• Local expertise adapted to the Quebec climate

LogisVert Subsidy: a financial advantage to consider

The current page indicates a provincial LogisVert subsidy of $1,250 for this product, updated on November 26, 2025. As programs can change, we always recommend verifying the conditions at the time of purchase. At AirGreen, we help our clients better understand the eligibility criteria, required documents, and information to keep after installation.

For many homeowners, this subsidy can make a significant difference in the net cost of the project, especially when comparing a multi-zone heat pump with several separate solutions.

A Good Heat Pump Starts with a Good Technical Visit

The product is important, but the technical visit is just as much so. When an AirGreen advisor visits, the goal is not just to sell a machine. We evaluate the house, constraints, occupants' habits, possibilities for line routing, and the expected aesthetic result.

In a house in Longueuil, for example, a client may want a head in the living room and another in the master bedroom, but the shortest route for the lines may not be the most visually clean. In Montreal, a narrow backyard may necessitate a wall mount or a carefully positioned ground base. On the North Shore, houses with large plots sometimes offer more flexibility but require special attention to snow and wind. On the South Shore, rear extensions and solariums may require more precise sizing.

These details explain why two installations with the same model can have very different results.

Who this model is best suited for

This HITACHI airHome Multi wall-mounted heat pump is particularly suitable for homeowners who want to:

• Heat and cool two separate zones
• Reduce the number of outdoor units
• Improve summer comfort in multiple rooms
• Add efficient auxiliary heating down to -20 °C
• Replace window air conditioners
• Improve the exterior appearance of their installation
• Choose a recognized brand with a solid warranty
• Anticipate a possible evolution to more zones depending on the configuration
• Obtain a solution compatible with indoor units of different capacities

It is less suitable when a client wants to heat an entire highly compartmentalized house with only two heads, or when the targeted rooms have no logical connection with possible piping routes. In these cases, we sometimes suggest another configuration or another model, to protect the client's comfort and budget.

Our Professional Recommendation

For a serious 2-zone installation, the HITACHI airHome Multi 2-Head Wall-Mounted Heat Pump | 36,000 BTU Compressor represents a very relevant option when the project requires good capacity, flexibility of indoor heads, and a clean installation with a single outdoor unit. It combines multi-zone comfort, R-32 refrigerant, heating capacity down to -20 °C, ENERGY STAR eligibility, smart control options, and a design conceived for durable residential use.

At AirGreen, we see it as a solid solution for homeowners who want true distributed comfort, without falling into an excessive or poorly adapted installation. The success of the project will always depend on the correct choice of capacities per room, the right placement of heads, and impeccable technical execution.

Contact AirGreen for a Clear and Adapted Quote

To get a precise recommendation, a free on-site estimate, or a comparison with other multi-zone systems, contact AirGreen today. Our team serves Montreal, Laval, Longueuil, the North Shore, the South Shore, and the Montérégie region with comprehensive solutions in wall-mounted heat pumps, HVAC installation, HVAC maintenance, air conditioning, and residential heating.