A den, a nursery or a converted box room is usually the room nobody plans for. It ends up with a portable unit on the floor, a trailing hose and a window propped open around it.

This configuration gives it a proper zone of its own at 9,000 BTU, alongside three 12,000 BTU indoor units for the main rooms. Only the zones that are switched on draw from the 38,000 BTU outdoor unit.

Four rooms, one box outside

The tinted rooms are the four zones and the blue line tracing down the wall is the refrigerant run. One outdoor unit sits at the side of the house instead of four window boxes across the front. Each zone needs a small cored hole and a tidy line cover, not a duct chase.

What is actually in the cartons

Counted out, it is four indoor units, one outdoor unit, four remotes with holders, four gas pipes and four liquid pipes at 16 ft each, four communication wires, four drain hoses, four wall sleeves and four screw kits, with tape, putty and wall caps supplied eight up. The copper is the expensive part and it is already in the box.

Phone, remote or voice

Every zone answers three ways: the app on your phone, the handset that ships with each indoor unit, or a voice command through Alexa or Google Home. The app screen in the photo shows one zone at a time, which is how you end up running two zones and leaving two off without thinking about it.

One house, four set points

Four rooms, four numbers, one outdoor unit. The drawing shows a kitchen, a dining room, a study and a bedroom each holding their own temperature. A room nobody is in can be switched off entirely, which is the part a single whole house thermostat cannot do.

One 38,000 BTU outdoor unit runs all four indoor units. Each zone starts, stops and holds its own temperature, so an empty room costs nothing to leave alone.

A common rule of thumb is 20 to 25 BTU per square foot (Carrier publishes 25). On that basis a 9,000 BTU unit suits roughly 360 to 450 sq ft and a 12,000 BTU unit suits roughly 480 to 600 sq ft. Natural Resources Canada points to CSA F280-12 for a proper load calculation.

The compressor varies its speed instead of cycling on and off. Published ratings are 20 SEER2 for cooling and 9.5 HSPF2 for heating on R32 refrigerant.

A chassis electrical heater keeps the outdoor base pan clear. The manufacturer rates heating down to -20°C (-4°F) and cooling up to 53°C (127°F).

Each zone gets a 16 ft insulated copper line set and 19 ft of communication wire, plus a 8 ft drain hose. That is the material most quotes list separately, four times over on a system this size.

The outdoor unit runs on 208-230V 60Hz. This is not a standard 15 amp household outlet. It wants its own branch circuit, sized from the MCA and maximum breaker figures on the unit's own nameplate, with a disconnect within reach.

Wifi app, a remote with a digital display for each zone, and voice control through Alexa or Google Home. A 24 hour timer and a child lock are built in.

The indoor filters pull out, rinse under a tap and go back in. Four heads means four sets, and clean filters are the cheapest way to keep airflow and running cost where they should be.

Ships from our United States warehouse. Delivery to Canada usually takes 8 to 14 business days, with no customs charges or duties to pay on arrival. Free shipping on orders over $150, a flat $18.90 below that, and tracking by email as soon as it leaves.

Return within 14 days of purchase, unused, in original condition and packaging.

Covered directly by the manufacturer under their warranty terms for material and manufacturing defects.

Found it cheaper at a Canadian retailer? Send us the link and we will match that price. It has to be the same item, in stock, sold and shipped inside Canada, and compared like for like on what comes in the box.

The 9,000 BTU zone suits a small room of roughly 360 to 450 sq ft. The three 12,000 BTU zones cover the larger rooms at roughly 480 to 600 sq ft each.

Older houses, additions, attic conversions and finished basements rarely have duct where it is needed. Four zones from one outdoor unit avoids opening up ceilings.

This is a heat pump, not a cooling only air conditioner. It carries a 9.5 HSPF2 heating rating and a chassis electrical heater on the outdoor unit for cold weather.

What we stand behind

• Ships from our United States warehouse, free shipping over $150, and 14 day returns unused in the original packaging.
• 14 day returns on unused items in original condition and packaging
• Covered by the manufacturer's own warranty for material and manufacturing defects
• Line sets, communication wire and a controller for every one of the four zones are in the box

How much space will each indoor unit cover?

Sizing runs off the heat load of the room, not just its floor area, and Natural Resources Canada points to CSA F280-12 for the real calculation. As a rough check, 20 to 25 BTU per square foot is the usual rule of thumb. On that basis a 9,000 BTU unit suits roughly 360 to 450 sq ft and a 12,000 BTU unit suits roughly 480 to 600 sq ft. Poor insulation, large west facing windows or a 9 ft ceiling all push the figure up.

The four indoor units add up to 45,000 BTU but the outdoor unit is 38,000 BTU. Is that a mistake?

No. On any multi zone system the indoor ratings are not meant to be added together, and multi zone sizing guides say so plainly. The 38,000 BTU figure is what the outdoor unit can deliver at one time, shared among whichever zones are calling for it. Four rooms rarely peak at the same moment, which is why this combination is offered.

How cold can it get outside before it stops heating?

The manufacturer rates low ambient heating down to -20°C (-4°F), helped by an electric heater in the outdoor chassis. Natural Resources Canada notes that air source heat pumps lose capacity and efficiency as it gets colder, with typical COPs falling from 2.0 to 5.4 at 8°C to 1.1 to 3.7 at -8°C, and that most newer units have a minimum operating temperature between -15°C and -25°C. Keep a backup heat source for the coldest stretches.

Can I install this myself in Canada, and does it run on a normal outlet?

No on both counts. The outdoor unit runs on 208-230V 60Hz, so it needs its own branch circuit and an electrician, not a wall socket. Refrigerant work is also regulated: Ontario, for example, states that only a certified technician may remove, discharge, handle and dispose of refrigerants including HFCs, and that mechanical work on refrigeration equipment needs a Certificate of Qualification on top of that. Other provinces have their own halocarbon rules, and the federal Code of Practice says the same thing in plainer terms.