FORESTAIR MZ R454B 2-Zone Wall-Mounted Heat Pump | Ext: 27000 BTU
The ForestAir MZ R454B 27 000 multi-zone heat pump heats and cools 2 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.
2 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 adapted to Quebec's realities
At AirGreen, we regularly install multi-zone wall-mounted heat pumps in residences and multiplexes in Montreal, Laval, Longueuil, North Shore, and South Shore. The FORESTAIR MZ R454B 27,000 BTU model stands out as a particularly balanced solution for owners who want to cool and heat two distinct zones with a single outdoor compressor, while maintaining excellent energy efficiency.
This system addresses a common problem we observe in the field: how to effectively manage different rooms (e.g., a living room and a bedroom) without multiplying outdoor units, while ensuring stable comfort during Quebec winters.
Why choose a 2-zone heat pump like the FORESTAIR MZ 27,000 BTU
Ideal flexibility for modern homes
The dual-zone configuration allows connecting two indoor units, with the possibility of up to three zones in total. This means:
- Independent temperature control in each room
- Better energy consumption management
- More discreet installation (one outdoor compressor)
In several projects carried out in Boucherville and Laval, we installed this type of system to replace inefficient old electric appliances. The result: a significant reduction in heating costs, while improving overall comfort.
Performance adapted to Quebec winters
This heat pump offers heating capacity down to -25°C, an essential criterion in our climate. In practice:
- Power at -8°C: 22,400 BTU
- Power at -15°C: 19,800 BTU
This means that, in most situations in Montreal and on the South Shore, the system can provide primary heating without constant reliance on electric backup.
According to the manufacturer's technical data, the unit maintains stable operation within a heating range from -25°C to 30°C, confirming its robustness in real conditions.
Energy performance and real-world efficiency
Solid energy ratings
The FORESTAIR MZ 27,000 BTU model features:
- SEER2: 24.0
- HSPF2: 10.5
- EER2: 12.0
- COP: 3.50
These values indicate excellent efficiency in air conditioning and heating, particularly attractive for owners looking to maximize their eligibility for subsidies like LogisVert ($2688).
DC Inverter Technology: a concrete advantage
Thanks to DC Inverter technology, the compressor continuously adjusts its power:
- Fewer on/off cycles
- More stable temperature
- Reduced electricity consumption
At AirGreen, we find that this technology makes a noticeable difference in open-concept homes or modern condos.
The new R-454B refrigerant: a forward-looking choice
This heat pump uses R-454B gas, a greener alternative to older refrigerants.
Advantages:
- Reduced environmental impact
- Better compliance with future standards
- Improved thermal performance
In a context where regulations are evolving rapidly in Quebec and Canada, this type of system represents a sustainable investment.
HVAC Installation: what we've learned in the field
Real example in Longueuil
We recently installed this heat pump in a duplex:
- Zone 1: living room + kitchen
- Zone 2: master bedroom
Challenges encountered:
- Limited piping passage
- Optimization of unit positioning
AirGreen solution:
- Use of discreet conduits
- Precise length adjustment (respecting limits: max 60 m total according to technical data)
- Airflow calibration
Result:
- Uniform comfort
- Very low noise level
- Client satisfied with independent zone management
Essential technical details to know
Key specifications
- Capacity: 27,000 BTU
- Voltage: 220V
- Outdoor sound level: 62 dB(A)
- Outdoor dimensions: 38.5 x 16.63 x 31.63 in
- Refrigerant: R-454B
- Connections:
- Gas: 3/8
- Liquid: 1/4
Lengths and installation
- Maximum total length: 60 m (197 ft)
- Maximum length per zone: 30 m (98 ft)
- Maximum elevation: 10 m (33 ft)
This data is crucial for a successful installation. Poor length management can lead to:
- Loss of performance
- Pressure problems
- Premature compressor wear
At AirGreen, we systematically validate these parameters before each installation.
Acoustic comfort and design
The indoor sound level varies between 30 and 46 dB(A) depending on the units chosen. This corresponds to a very quiet environment, ideal for:
- Bedrooms
- Home offices
- Living spaces
We often recommend this model for noise-sensitive clients, especially in condos in downtown Montreal.
HVAC Maintenance: common mistakes to avoid
Even with a high-performance system, poor maintenance can significantly reduce its lifespan.
What we often see:
- Uncleaned filters
- Blocked drain
- Outdoor units obstructed by snow
Best practices:
- Clean filters every 1 to 3 months
- Annual professional maintenance
- Drainage check
Proper maintenance helps maintain performance and avoid costly repairs.
Why choose AirGreen for your FORESTAIR heat pump
Proven field expertise
We have installed hundreds of multi-zone systems in:
- Montreal
- Laval
- Longueuil
- North Shore and South Shore
Each project is unique, and our approach is based on:
- Precise needs analysis
- Adapted sizing
- Installation compliant with RBQ standards
Transparency and support
- Detailed quotes
- No surprises
- Clear explanation of options
Efficient after-sales service
Our refrigeration technicians respond quickly if needed, with in-depth knowledge of FORESTAIR systems.
Conclusion: a balanced, efficient, and durable heat pump
The FORESTAIR MZ R454B 27,000 BTU 2-zone wall-mounted heat pump represents a solid solution for:
- Multi-room dwellings
- Owners seeking efficiency and flexibility
- Projects requiring a reliable system in winter
It combines performance, energy efficiency, and adaptability — three essential criteria in the Quebec context.
Take action with AirGreen
To obtain a personalized quote, a technical evaluation, or simply advice adapted to your property in Montreal, Laval, Longueuil, North Shore, or South Shore, contact AirGreen today.
We will assist you in the selection, installation, and maintenance of your HVAC system, with a professional and results-oriented approach.
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 2 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.