FORESTAIR MZ R454B 3-Zone Wall-Mounted Heat Pump | Ext: 27000 BTU
The ForestAir MZ R454B 27 000 multi-zone heat pump heats and cools 3 rooms with a single outdoor unit. it delivers 22,400 BTU/h at −8 °C, heats down to −25 °C and qualifies for a $2,688 LogisVert grant. Installed by AirGreen in Montréal, Laval, Longueuil, the North Shore and the South Shore.
3 rooms, one outdoor unit.
Compared with the 26 multi-zone systems of 27,000 BTU we sell. Every number on this page carries its source.
The parts that make a multi-zone system.
Tap a part to learn more.
Outdoor unit
One compressor for the whole house. It supplies up to 3 heads and modulates from 4,500 to 22,500 BTU/h depending on what the rooms call for (NEEP).
Base pan heater
A heater keeps the outdoor unit’s base pan free of ice below 1 °C and during defrost (NEEP).
Refrigerant lines
One pair of lines per head.
Indoor heads
One head per room, each with its own remote and temperature. The combination is chosen in the “Zones” menu.
Control
Each zone is set separately, also from your phone.
Turn rooms on and off. Watch the power being shared.
One outdoor unit supplies every head: when several rooms call at once, they share its capacity. Pick an outdoor temperature.
Tell us your rooms. We tell you if this size is enough.
Pick the number of rooms and their size. The estimate targets a −15 °C day; it is a guide, the real calculation is done room by room at your home.
The whole series at a glance: find the box that fits you.
Each box is a product: the outdoor unit’s size, and the number of heads.
At −15 °C, it still delivers 73 % of its rated capacity.
Tap a temperature: certified capacity, efficiency and the cost of one hour of heating.
It slows down, it speeds up: the certified modulation range
Light bar: from minimum to maximum capacity. Dark mark: the rated value.
At every temperature, cheaper than baseboards.
Cost of one hour at full output, for the same heat delivered. Hydro-Québec Rate D, second tier: 11.142 ¢/kWh.
The official ratings, on the same scales as before.
SEER2, HSPF2 and EER2 come from the AHRI certification. The mark shows the median of the same-size multi-zone systems we sell.
A grant you can calculate, not guess.
The capacity at −8 °C comes from Hydro-Québec’s list of October 1, 2026. $120 per 1,000 BTU/h is the rate for ENERGY STAR cold-climate heat pumps (guide v1.10).
Where it ranks among same-size multi-zone systems.
Compared with the 26 multi-zone systems of 27,000 BTU we sell, using the LogisVert list figures. Weaknesses too, said plainly.
Against three other brands in its class.
Same rated size, other manufacturers. Pick the opponent.
One multi-zone or several wall units? Both sides, honestly.
We compare both options on your floor plan during the estimate.
What to know before installing a multi-zone system.
Dimensions, wiring and lines, drawn. Then our six steps.
The outdoor unit, dimensioned
One circuit for the whole house
Published sound levels, on one scale.
We use the outdoor figure to choose where the unit goes.
What is particular about this machine.
Only facts published by ENERGY STAR, NEEP or the manufacturer.
Every number, and where it comes from.
Each line carries its source; a line with no published value is not shown.
The manufacturer’s documentation, as PDF.
Everything we have written about this system.
A high-performance multi-zone HVAC solution designed for Quebec's climate
At AirGreen, we regularly install multi-zone systems in homes and multiplexes in Montreal, Laval, Longueuil, on the North Shore, and the South Shore. The FORESTAIR MZ R454B (27,000 BTU) wall-mounted heat pump stands out as a solution particularly well-suited to local realities: extreme temperatures, the need for precise zoning, and the pursuit of energy efficiency.
This model is not limited to air conditioning a single space—it intelligently manages three independent zones with a single outdoor unit, while maintaining stable performance down to -25 °C.
Why choose a triple-zone heat pump like the FORESTAIR MZ?
A concrete answer to the needs of Quebec properties
In practice, a large part of the projects we carry out at AirGreen concern:
- Houses with multiple floors
- Duplexes or triplexes with distinct needs per room
- Extensions or renovations without central ducts
In these cases, a multi-zone wall-mounted heat pump offers a key advantage: controlling the temperature room by room, without compromise.
Real-life AirGreen installation example
In Boucherville (South Shore), we recently installed this FORESTAIR model in a renovated bungalow:
- Living room + kitchen (12,000 BTU)
- Master bedroom (9,000 BTU)
- Finished basement (9,000 BTU)
Result:
- Noticeable reduction in on/off cycles
- Uniform comfort in all zones
- Optimized energy consumption thanks to the DC inverter
Detailed technical specifications of the FORESTAIR MZ 27,000 BTU
Performance and energy efficiency
- Cooling capacity: 27,000 BTU
- Effective heating capacity down to -25 °C
- Power at -8 °C: 22,400 BTU
- Power at -15 °C: 19,800 BTU
- SEER2: 24.0
- HSPF2: 10.5
- COP: 3.50
These data are confirmed in the official technical documentation, which also highlights the stability of performance even in severe winter conditions.
Technology and design
- High-efficiency DC Inverter compressor
- Intelligent defrosting
- Quiet operation (62 dB outdoor)
- WiFi included for remote control
- ENERGY STAR® compatible (including cold climate)
Exceptional operating range
- Cooling: -15 °C to 55 °C
- Heating: -25 °C to 30 °C
This point is essential for customers in Montreal and Laval, where temperature variations are significant.
The new R-454B refrigerant: a strategic choice
The FORESTAIR MZ uses R-454B gas, a significant evolution in the HVAC field.
Concrete advantages
- Reduced environmental impact (lower GWP)
- Improved thermal efficiency
- Compliance with future environmental standards
At AirGreen, we strongly recommend systems using this type of refrigerant, as they ensure long-term sustainability for homeowners.
HVAC installation: what you really need to know
Essential technical data for installation
According to the technical sheet:
- Voltage: 208-230V / 1 phase / 60 Hz
- MCA: 18A
- Circuit breaker: 30A
- Maximum elevation: 10 m (33 feet)
What we see in the field
A common mistake among less experienced installers is improperly balancing line lengths between zones. This can lead to:
- Loss of efficiency
- Increased noise
- Poor heating performance
At AirGreen, we systematically optimize:
- The positioning of indoor units
- The routing of refrigerant lines
- Electrical sizing
Flexibility of indoor combinations
This system allows for several configurations:
- 9 + 9 + 9
- 9 + 12 + 12
- 12 + 12 + 12
- 9 + 9 + 18
This provides great flexibility to adapt the system to the realities of each property.
Concrete case in Laval
In a duplex in Laval, we combined:
- 18,000 BTU on the ground floor
- 9,000 BTU in each bedroom upstairs
This allowed for:
- Better management of thermal loads
- A reduction in the annual energy bill
Noise level and daily comfort
- Indoor: 30 to 46 dB(A)
- Outdoor: 62 dB(A)
In residential neighborhoods in Longueuil or Montreal, this noise level is particularly appreciated.
We have already replaced older noisy systems with this model, with immediate customer feedback:
"You can barely hear anything anymore, even at night."
Dimensions and aesthetic integration
- Outdoor unit: 38.5 x 16.63 x 31.63 inches
- Compact and discreet design
On the North Shore, several customers want to preserve the exterior aesthetics of their homes. This model integrates easily:
- On a wall mount
- On a ground slab
- Behind landscaping
Subsidies and profitability
- LogisVert subsidy: $2,688
This amount may vary according to installation criteria but remains a significant lever for reducing the initial cost.
Return on investment
In several projects carried out by AirGreen:
- Annual savings: 25 to 40%
- Payback period: 4 to 7 years
What we have learned about this model
After several installations, here are the key points:
Strengths
- Very good actual heating performance
- Stable multi-zone performance
- Flexible installation
Points to watch out for
- Requires precise installation
- Essential zone optimization
- Importance of proper initial sizing
Why choose AirGreen for your HVAC installation
At AirGreen, we make a difference through:
- Concrete field expertise in HVAC in Montreal, Laval, Longueuil
- Optimized, not standardized, installation
- Total price transparency
- Experienced refrigeration technicians
- Insurance coverage of $5,000,000
Each project is designed to maximize:
- Comfort
- Energy efficiency
- System durability
Conclusion: a reliable multi-zone heat pump adapted to Quebec
The FORESTAIR MZ R454B 27,000 BTU 3-zone wall-mounted heat pump represents an excellent choice for:
- Multi-room houses
- Duplexes/triplexes
- Ductless renovation projects
It combines performance, flexibility, and energy efficiency, while being perfectly suited to Quebec's climatic conditions.
Get a personalized quote with AirGreen
Are you considering installing a multi-zone heat pump in Montreal, Laval, Longueuil, North Shore, or South Shore?
Contact AirGreen today for:
- A free evaluation
- A customized configuration
- A clear and detailed estimate
Our team supports you from system selection to complete installation.
Warranty: 10 years on the compressor, 10 years on parts and 6 years on labor, straight from the distributor.
What people ask us about multi-zone systems.
Can I heat one room and cool another at the same time?
No. On a multi-zone system like this one, every head works in the same mode, heating or cooling. Each room still keeps its own set temperature.
What happens when every room calls for heat?
They share the outdoor unit’s capacity: 22,400 BTU/h at −8 °C, 19,800 at −15 °C.
How many heads can I connect?
Up to 3 on this outdoor unit. This product is configured for 3 heads.
How much is the LogisVert grant?
$2,688 according to Hydro-Québec’s list of October 1, 2026. The grant never exceeds 100 % of the cost before taxes; apply within 9 months of installation.
Is it ENERGY STAR certified?
Yes, cold climate, ID 4529623. It also meets the ENERGY STAR Most Efficient criteria, according to the ENERGY STAR database.
Down to what temperature does it heat?
Down to −25 °C.
Is it noisy?
Indoors, the reference head goes down to 30 dB(A). Outdoors, 62 dB(A): we place the unit away from bedroom windows.
Why a multi-zone instead of several wall units?
One outdoor unit on the wall and one circuit. In return, the rooms share the capacity, and if the outdoor unit stops, every zone stops.
What does the warranty cover?
Our sheet lists 10 years on the compressor and 10 years on parts. AirGreen extended warranty: possible.
A multi-zone system is planned room by room. At your home.
We measure every room, draw the line route and choose the right head for each zone. The on-site estimate is free and the quote arrives within 24 h.