GENERAL AIRSTAGE Aquila R32 QuadZone Heat Pump | 45,000 BTU | Montreal, Laval, South Shore, North Shore

GENERAL AIRSTAGE Aquila 4-Zone 45,000 BTU Heat Pump: four apartments, four wall-mounted heads, one compressor, installed by AirGreen

This GENERAL AIRSTAGE Aquila 4-zone multi-zone system is, part for part, the Fujitsu AIRSTAGE Aquila system built around the AOUH45KWAS5 outdoor unit: same 45,000 BTU Inverter compressor, same four zones, same starting configuration of 7,000 + 7,000 + 7,000 + 7,000 BTU, same AHRI certificate 215735280, same certified values, same warranty. What changed is the name on the box: Fujitsu General Limited became GENERAL Inc. on January 1, 2026, and the machine our refrigeration technicians pull out of the truck is exactly the one they already know.

We picked it for one specific case: the fourplex in Montréal-Nord or Saint-Léonard, four apartments stacked or side by side, four tenants who do not want the same temperature, and an owner who does not want four outdoor units lined up in the back lane. One outdoor unit on the roof or on the ground, one 7,000 BTU wall-mounted head per apartment, one setpoint per tenant. The 45,000 BTU compressor accepts up to 5 zones, which leaves a free port for a fifth space later on.

Four 7,000 BTU heads is the right format for a typical plex apartment: the head goes in the main room, blows toward the hallway, and the tenant sets the temperature to taste. In summer, everyone cools their own apartment; in winter, everyone heats their own way and the existing electric baseboards stay in place as backup on the coldest days. For the owner, that means one machine to maintain, one electrical feed and one maintenance visit to plan instead of four.

GENERAL or Fujitsu AIRSTAGE: the same machine

The name change comes from a transaction, not from a new product line. In August 2025, Paloma Rheem Holdings, owner of Rheem since 1988, acquired Fujitsu General Limited. On January 1, 2026, the company became GENERAL Inc.: same head office and same research centre in Kawasaki, Japan, same factories, same AIRSTAGE products, same model numbers, same warranty program. The GENERAL name is nothing new either: the brand has been in use since 1946, and the company, founded in 1936, marks the 90th anniversary of its founding in 2026. Since February 2026, Rheem Canada has handled sales in this country, and Groupe Master remains our distributor, as before.

During the transition, the Fujitsu brand is gradually disappearing from the packaging and the same machine circulates under both names. That is why we keep both pages online: you may land here after searching for "Fujitsu Aquila 4 zones" or after reading "GENERAL" on a label, and in both cases you are looking at the same AOUH45KWAS5 with the same AHRI certificate. The table below puts the two pages side by side, value for value.

The twin page under the former name is here: Fujitsu AIRSTAGE Aquila 4-zone 45,000 BTU. Same warranty, same AirGreen installation, same service after the install; simply pick the page that carries the name you know.

Let's talk performance, because that is where this compressor stands out. The values that follow come from NEEP (ashp.neep.org), under AHRI certificate 215735280, not from a brochure: 31,000 BTU/h of rated capacity at −8 °C, with a COP of 2.96 and measured peaks of 41,000 BTU/h, then up to 36,000 BTU/h at −15 °C with a COP of 2.14. COP is the ratio between heat delivered and electricity consumed: a COP of 2.96 means every kilowatt-hour you pay Hydro-Québec comes back as nearly three in heat inside your apartments. At −15 °C, an electric baseboard still returns one for one; this heat pump still returns more than two.

The SEER2 of 22.0 and the EER2 of 12.0 describe summer: the higher the number, the less cooling costs in electricity for the same comfort. The HSPF2 of 10.0 describes the whole winter, not a single day: it is the total heat delivered over the season divided by the total electricity consumed, measured under the most recent standard. That combination earns the model the ENERGY STAR Most Efficient label on top of its cold-climate designation. Heating is guaranteed down to −15 °C; below that, the apartment's electric backup takes over for the harshest January nights.

The rest of the comfort comes from the Inverter compressor. Its certified minimum capacity is 12,000 BTU/h: when a single apartment calls, it slows down instead of stopping and restarting, which keeps the temperature steady and avoids the short cycles that wear a machine out. Each zone has its own setpoint and its own remote; one tenant can sleep cool while the neighbour works warm. One rule to know: all the heads connected to the same compressor run in the same mode, heating or cooling, which bothers no one in Quebec, where everyone heats in the same month.

The configuration on this page brings together four 7,000 BTU wall-mounted heads, but nothing is locked in: you choose your indoor units with us, room by room, among the models compatible with the AOUH45KWAS5:

• ASUH07KPAS, 7,000 BTU: bedroom, office, small plex living room.
• ASUH09KPAS, 9,000 BTU: medium living room or a very open apartment.
• ASUH12KPAS, 12,000 BTU: open kitchen and living area.
• ASUH15KPAS, 15,000 BTU, and ASUH18KPAS, 18,000 BTU: large apartments or the owner's unit across two connecting rooms.
• ASUH24KPAS, 24,000 BTU: a full, open-plan floor.

The compressor accepts up to 5 zones. A fourplex with one apartment larger than the others can therefore take three 7,000 BTU heads and one 12,000 BTU head, and keep a fifth port for a basement bedroom or a workshop. We size each head on site, room by room, taking orientation, windows and insulation into account, not from a generic chart.

An AirGreen installation follows a simple logic: a single outdoor unit, then one refrigerant line per head. In a plex, the outdoor unit most often goes on the flat roof or on a ground stand at the back, where it bothers neither the parking nor the neighbours; it is 37 inches wide, runs at 56.0 dB(A) and needs clearance for air and for snow. From there, four insulated lines run up or down to the apartments, usually in a cover along the back wall, each with its control cable. Each wall-mounted head is set high on a wall that faces outside or close to where the lines rise, and its condensate drain flows by gravity to the outside or to a pump when the slope is not enough. The electrician connects a single feed for the compressor; that is a point to settle in the lease, since the heating for all four apartments goes through one meter.

Day-to-day maintenance is within the tenants' reach: each head has washable indoor filters that slide out by hand and rinse under warm water; a clean filter keeps the airflow and the efficiency. The rest belongs to the refrigeration technician: checking the R-32 charge, cleaning the outdoor coil, inspecting drains and connections. R-32 itself is an argument: its global warming potential is 675, versus 2,088 for R-410A according to ENERGY STAR.

On the financial side, the AOUH45KWAS5 is listed on Hydro-Québec's LogisVert list with an amount of $3,720 as of today. The eligibility conditions are Hydro-Québec's and vary with the type of building; we check them with you when we prepare the quote rather than promising a figure blindly. The warranty is the AIRSTAGE program's: 12 years on the compressor, 12 years on parts and 6 years on labour. Wi-Fi control is offered as an option, head by head, for tenants who want to adjust their apartment from their phone.

This system is made for the fourplex owner who wants to settle the comfort of all four apartments in one go, without ducts, without drilling the back wall four times for four outdoor units, and without hearing four compressors run. It also suits the three-generation home or the large Saint-Léonard house with four bedrooms far apart from one another, where a single central unit would never satisfy everyone. And since it is the same machine as the Fujitsu version, you give up nothing in the transition: same parts, same trained technicians, same distribution network.

Free quote in Montréal-Nord, Saint-Léonard and across Greater Montreal

We install this multi-zone system in Montreal, Laval, Longueuil, on the North Shore and on the South Shore, and we know the flat roofs and back lanes of Montréal-Nord and Saint-Léonard. Call us at 514 316-2973 or request your free quote online: an advisor comes to see the plex, counts the zones with you and hands you a clear price for the AOUH45KWAS5 and its heads, under the GENERAL name or the Fujitsu name, your choice.

AirGreen is an AIRSTAGE Elite Plus installer and an RBQ-licensed HVAC contractor: the quote, the installation, the commissioning and the after-sales service are all done by our own team.