Choosing between a mono and multizone heat pump to get through the harsh winters of Montréal, Laval, Longueuil, North Shore and South Shore
At AirGreen, we understand that selecting the right wall-mounted heat pump for your property can transform your indoor comfort during the freezing winters of Greater Montréal. Whether you own a bungalow in Laval, a triplex in Longueuil, or a century-old home on the South Shore, one question comes up often: should you go for a mono or multizone system to handle Québec’s extreme cold temperatures?
Thanks to our field expertise and the many heat pump installations we’ve completed, we’ve put together this practical, detailed, and unique guide to help you make an informed decision.
Understanding the difference: mono vs multizone
Monozone heat pump
A wall unit connected to a single outdoor compressor, designed to heat and cool one single zone in your home — typically a main room like the living room.
Multizone heat pump
One outdoor compressor connected to several indoor units (usually 2 to 5), allowing you to control different zones independently within the home.
The specific challenges of Montréal’s climate
Winters in Québec can easily dip below -20°C, with long stretches of extreme cold. In this context, every decision regarding your HVAC heating system becomes critical.
We’ve seen on the field that certain brands like Gree, Fujitsu, Bosch, and Sharp, equipped with advanced vapor injection technology or Inverter compressors, offer reliable performance even at -30°C. This applies to both monozone and multizone systems — as long as you choose the right model for your setup.
Advantages of a monozone system
1. Lower initial cost
One of the biggest advantages of a monozone heat pump is its affordable price. For a client in Sainte-Thérèse, North Shore, we recently installed a Gree Lomo+ 12,000 BTU to heat the living room. The result: improved energy efficiency and noticeable savings on the very first Hydro-Québec bill.
2. Quick and discreet installation
With only one indoor unit, the work is often done in a single day. Less impact on the structure, fewer holes drilled, and ideal flexibility for small spaces.
3. Perfect for condos or small homes
For a client in Verdun, a Fujitsu KZAH 15,000 BTU efficiently covered an open space combining kitchen and living room in a condo. No need to manage multiple thermostats.
Advantages of a multizone system
1. Independent control of each room
Large families or homes with multiple floors greatly benefit from individual temperature control per room. In Longueuil, we installed a Fujitsu multizone heat pump with three wall units in a single-family home: living room, master bedroom, and basement. Each room now has its personalized temperature.
2. Ideal solution for large homes
For homes over 2,000 sq. ft., a multizone system is often the only effective way to ensure even heating. That’s what we recommended for a heritage home in Outremont, where thick walls and multiple distinct volumes made a monozone system inadequate.
3. Fewer outdoor units visible
One outdoor compressor for 3 to 5 indoor units: an aesthetic and practical solution, especially in urban areas where city bylaws on exterior occupancy can be strict.
Key selection criteria: mono or multi?
Home size
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Under 1,000 sq. ft.: Monozone recommended.
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1,000 to 2,500 sq. ft.: Multizone preferable.
Number of occupants
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1 to 2 people in an open space = Monozone.
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Family with children, closed rooms = Multizone.
Available budget
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Tight budget: start with a monozone in the main room, with the option to add more zones later.
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Larger budget: go full multizone from the start to maximize comfort and efficiency.
Available grants
Both system types may qualify for Hydro-Québec’s LogisVert grants, depending on the chosen model. For instance, a Sharp ZU1 24,000 BTU monozone in Oka allowed a client to get a $2,172 rebate. A multizone project in Saint-Lambert unlocked a total grant of over $3,500 thanks to the installation of three eligible units.
Recent AirGreen projects: real-world examples
Laval – Two-storey home, multizone Bosch BOVA 36,000 BTU
Three wall-mounted units were installed in the bedrooms, plus one console in the basement. Stable temperature even during the January snowstorm. The client was thrilled with a 35% reduction on their electricity bill.
Montréal – Apartment, monozone Gree Lomo+ 18,000 BTU
Perfect for an open-concept kitchen/living room. One-day installation, no structural changes. Excellent client feedback on the low noise level and performance at -25°C.
Mistakes to avoid
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Choosing an oversized multizone for a small home = inefficiency and waste.
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Skipping proper BTU sizing = poorly heated rooms.
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Ignoring the impact of indoor unit placement, especially during renovations.
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Forgetting proper drainage planning in winter = freezing risk.
Why trust AirGreen?
Our certified technicians understand the realities of Montréal’s climate. We take into account:
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Your home’s actual insulation level.
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Room orientation.
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Your lifestyle habits.
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Available financial aid.
Every HVAC installation is personalized, transparent, and built to last.
Our verdict
Monozone heat pump: perfect for small spaces, tight budgets, or as a starter project.
Multizone heat pump: the complete solution for customized comfort throughout your home.
At AirGreen, we’re here to help you choose, install, and maintain your wall-mounted heat pump, whether you're in Montréal, Laval, Longueuil, on the North Shore or South Shore.