GENERAL AIRSTAGE INFINITE COMFORT 36LMAS1 3 Ton Central Heat Pump in Montreal, Laval, Longueuil, South Shore and North Shore

One Central Heat Pump for Both Floors: GENERAL AIRSTAGE INFINITE COMFORT 36LMAS1, AMUG36LMAS 36,000 BTU Air Handler

For a two-storey home, the 36LMAS1 system pairs the AMUG36LMAS air handler with the AOUG36LMAS1 outdoor unit. This pair is exactly the one we also sell under the Fujitsu AIRSTAGE name. Since January 1, 2026, the manufacturer has gone by the name GENERAL Inc.; its spec sheet and its warranty have not changed by a single line.

The classic North Shore case: a two-storey house with a basement, ductwork serving all three levels, and owners who are fed up with a stifling upper floor in July and a chilly basement in January. Instead of adding a wall unit on every floor, the whole duct network goes to a single central heat pump. In Saint-Joseph-du-Lac, between the orchards and the residential streets, this type of house is part of the landscape.

More good news: unlike some other systems in the same family, this one ticks the two boxes many owners look at first. It is ENERGY STAR Cold Climate certified and listed for LogisVert with a $3,528 grant.

GENERAL or Fujitsu AIRSTAGE: the same machine

The GENERAL name has been gradually replacing Fujitsu on AIRSTAGE products since Paloma Rheem Holdings, owner of Rheem, acquired the manufacturer in August 2025. For you, in practical terms, nothing moves: the unit comes out of the same factories, carries the same model number and falls under the same warranty program. Canadian sales have gone through Rheem Canada since February 2026, and we continue to source from Groupe Master.

Two pages, one system. We publish them side by side so the comparison takes a few seconds, and so you can choose the name you trust most.

The same machine also appears in our catalogue under its former name: Fujitsu AIRSTAGE INFINITE COMFORT 3-ton.

In a two-storey house, everything starts in the basement. The AMUG36LMAS air handler is most often installed there in upflow, where the furnace used to be, and feeds the ductwork that rises to the ground floor and the upper floor. Its multi-position design also allows downflow or horizontal mounting, with the kits provided at no extra cost, if the house calls for it. The unit measures 21 × 21.69 × 57 in. and requires minimum clearance on three sides, plus 21 in. at the front for service.

What a single system changes, level by level:

• upstairs, cooled air comes in through the grilles and drives out the heat that builds up under the roof by late afternoon;
• on the ground floor, one control sets comfort for the kitchen, living room and dining room, with no unit on the wall;
• in the basement, the unit takes back air from the whole house, filters it and redistributes it, which helps even out temperatures from one level to the next.

Pushing air up to the top floor is the real test of a three-level duct network. On the air side, the unit allows up to 1.0 in. WC of static pressure and a maximum airflow of 1,200 CFM. Its adaptive fan motor control and all-aluminum coil round out the picture. The ducts remain the deciding factor, though: an undersized riser or a single return air in the basement is enough to keep the upper floor hot in July. So we check the network during the visit, level by level, before confirming the system and the number of grilles.

On to winter, with the figures as published. At rated capacity, the manufacturer gives 36,000 BTU/h in cooling and goes up to 42,000 BTU/h in heating. The certified listing shows 29,400 BTU at −8 °C (COP of 2.62) and 32,800 BTU at −15 °C (COP of 2.0). These two measurements come from different test conditions; read them separately. The heating range goes down to −21 °C; beyond that, electric backup takes over, with the kit the manufacturer provides and that is installed on site in the unit.

The efficiency values to remember:

• SEER2 and EER2 in cooling: 17.1 and 10.7;
• seasonal heating: HSPF2 of 8.8;
• AHRI: certificate 205123809;
• ENERGY STAR: ID 2409794, cold climate category.

In the basement, the indoor unit produces 26 to 40 dB(A): you soon forget it is there. Outside, the spec sheet lists 54.0 dB(A) for a unit measuring 38.19 × 14.56 × 39.31 in. North Shore lots often have room to spare: we install it on a pad or stand, away from the deck and bedroom windows, taking into account the snow that slides off the roof.

The job starts with an inspection of the supply and return ducts. We then set the layout and the number of grilles if more are needed upstairs, and install the air handler, not forgetting the panel that gives access to the filter. The 3/8 and 5/8 in. refrigerant line runs with the cable and drain to the outdoor unit. Power is 208/230 V. A refrigeration technician handles commissioning, and AirGreen, an AIRSTAGE Elite Plus installer, takes care of the whole job.

On the electronics side, the outdoor unit and the indoor unit exchange information: the manufacturer presents the 36LMAS1 as a fully communicating heat pump whose indoor unit remains a conventional multi-position air handler. Wi-Fi can be added as an option. And if another appliance in the house needs to work in concert, the optional external input/output interface provides interlocking with that third-party system.

Maintenance happens in one place: the filter in the basement, reachable through the access panel. Keep the grilles clear on every floor, especially the returns, which often end up hidden behind furniture. Finally, the manufacturer's warranty protects the compressor for 12 years, the parts as well, and labour for 6 years.

Hydro-Québec has listed the 36LMAS1 system on its LogisVert list of October 27, 2026, with a grant of $3,528. Hydro-Québec sets the eligibility conditions; for the application, the AHRI certificate and the ENERGY STAR ID are already gathered in the table.

This system is aimed first at:

• the two-storey house with a basement, already fitted with ductwork;
• the owner who wants one central heat pump for every level rather than one unit per room;
• anyone who insists on ENERGY STAR Cold Climate certification and the LogisVert grant.

An honest clarification: without ducts, this is not the right solution, and a room far from the network may need a layout adjustment. These points get settled during the visit, not after installation.

Saint-Joseph-du-Lac: a free quote for your two-storey home

To have your ductwork assessed and receive a free quote, call AirGreen at 514 316-2973. The proposal can carry the GENERAL or Fujitsu name, your choice, and takes into account the LogisVert amount in effect at the time of your project.

As an HVAC contractor, we serve Saint-Joseph-du-Lac and the whole North Shore, as well as Montreal, Laval, Longueuil and the South Shore.